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In-depth FAQ
By destroyor
- general tips and tricks for new players
- game mechanic explained
- skill check thresholds
- psi mentor locations
- Expansion
- crafting & component reference
- final area (Spoiler alert!)
- cheat engine, duplication and item transfers
*note: contains spoilers, viewer discretion is advised.
This FAQ is for version of the game.

I am NOT affiliated in anyway with Stygian Software; They do NOT endorse this FAQ in any way. This FAQ contains publicly available information from Steam forum, official forum, official wiki and RPGCodex. Special thanks and credits are given in the special thanks section. If for whatever reason you don't want your post/name/whatever on this FAQ give me a shout and I'll remove them.

I will try to keep spoilers to a minimum and give ample warnings before them.

I need your help! If you see any misinformation/grammatical error/typo please add a comment below. Critique/feedback/comment/correction are welcome.

Latest Underrail version:
All sections in this guide are up to date, except:
Character build
Special thanks
Special thanks and credits to (in no particular order):

Official wiki for numerous information. I copied and pasted a lot of text from the official wiki and presented them here. This is because a lot of new players would not know where to look on the wiki without knowing the in game terminology.

Underrail official forum:
Wildan - pistol build, sniper build, crossbow build, knife build, sledgehammer build
hilf - chemical pistol build, final area advice, global merchant restock, final boss advice and various corrections
GawainBS, Hazard, Altos - SMG build
Kachajal - a more user-friendly Underrail speedhack
epeli - official wiki, build tool, underrail.info.tm, ambush explanation, Tchortist Noble Robe, noise system explaination
SubterminalOptimization - tips against final boss
Azura - wearing Tesla armor inside the graveyard
Hammer Wizard - Ultimate hammer guide
Koveras - Assault Rifle / Thought Control hybrid
Kiruha - Crossbow Dominating Build (without Aimed shot and snipe)
sheepherder - PTC debuff chance, various dominating viable build w/ distinct theme, comment on Force Emission

Underrail Steam forum:
Morgian, Racocac, Kirill-busido - psionic mentor locations
Altos - crossbow user advice, final area advice
st88 - psi user advice
Lord of Change - The Guide to playing Underrail optimally!
ihavefuzzylogic - duplication and item transfers trick
12 - Trapper's Belt
Frog Friend (Firestalker on official forum) - SMG build, SMG AP table
carashi - plasma pistol advice, sledgehammer build advice, final area advice
Quantum - Underrail Cheat Engine Guide
Flash - [Mod] Proofread Underrail
coslie - value of crafted item
harperfan7 - cave hopper leather quality
mindless - comment re: mercantile
elmo - stretching graphics to help see game better
Gachette Pure - corrections on armor resistance and threshold
Sutasu! - armor calculation correction
bye - How to edit/respec feats
akerbouchard11 - expansion correction
Survivor Grosjean - Hybrid Build - Versatility Crossbow + Chemical Pistol Build and Yet Another Hybrid Build - Shooting Spree Crossbow Marksman
Tamiore - comments on psi abilities

Cheat Engine forum:
SorbitolO - Underrail Cheat engine table

FearLess Cheat Engine forum:
Csimbi - Underrail Cheat engine table

GOG forum:
SEAJAR - realistic portrait pack

RPG Codex:
Damianus_NT - link to expedition map
Horvatii - https://rpgcodex.net/forums/threads/underrail-the-incline-awakens.105387/page-515#post-6715755

Reddit - Underrail subreddit
HappyRBX - Assault Rifle & Sniper Guide for Beginners (needs Expedition DLC)

Aether - Underrail Sniper & Assault Rifle Build Guide

Saitama Lisa/Mona Saitama - artwork by LadyGT, if you like her work please support her on Patreon. https://www.patreon.com/posts/3721590
General tips for new players part I
This section contains general tips for new players; Veteran players can skip this section.

  • Take advice with a healthy dose of scepticism, so please take things on this guide w/ barrel of salt. Constructive criticism and correction are always welcome. :)

  • Please understand what you are getting into before starting this brutal game. Easy difficulty is what's usually considered Normal/Medium for other games. Even RPG veterans will probably build their first couple characters in a sub optimal fashion and die a lot. Don't be afraid to play on easy, abuse your quicksave and quickload buttons and/or restart multiple times as that's expected of you for your first few games. Personally I love this game and find overcoming overwhelming odds by taking every single advantage the game mechanics offer to the limit extremely rewarding and satisfying.

  • There is nothing wrong with playing blind. However the learning curve is actually pretty steep and could be overwhelming for a new player: no respec; need to understand how effective + base abilities, skills and feats interact w/ each other; class specific good and bad feats (prime example: how would a new player even knows Perfect Scattering is garbage?); good (not even optimal) gear setup; armor penalty, resistances and damage reductions, etc. While you could play your first game without planning out your character in every detail, following a pre-made/recommended build will allow a newbie to ignore the char building part of the game while learning how the rest of Underrail plays - what works and what doesn't, general tactics, game mechanics, and gain foreknowledge for subsequent plays. The learning curve is significantly lower even when the player abandon the pre-made build half way through the game and decided to play his/her own build. When starting everything blind it's very likely to be frustrated, overwhelmed by information overload, overly relying on cheese (caltrops, grenades, bear trap just to name a few) due to playing an unoptimized/bad build or even abandon the game. Having a bad/unoptimized build can also end up making combat a lot harder unnecessarily. Make sure you are getting the most out of your class, try to maximize your damage output w/ your weapons, feats, skills, combat ulitities and traps. You can be soft-locked by playing a bad build.

  • The game is designed to have the odds stack against you. It's always a fight of many vs. you, all alone. Take things slow, and stealth is your friend.
    To avoid dying, you want to put on your best Motion Tracking Goggles, stealth armor set, and scout any new area under stealth to learn enemies' type, positions, their patrol route, area layout and to detect any possible traps.
    There's usually some sort of cover that will allow you to dodge enemies' line of sight, so use this to your advantage by ending your turn hiding behind walls/corner/rocks/etc. Running far, far way is another viable option - range enemies will now have decreased precision due to them being outside their weapons' optimal range; melee enemies can't hit you unless they are within melee range.
    Realistically it's a chore to stealth scout every single map. It's more like: playing normally until you enter a map with lots of enemies and/or traps everywhere where you promptly get ♥♥♥♥ -> reload -> ok ok this is a high danger area - time to put on motion tracking goggles, wear stealth set, take things slow and scout the entire map.
    Once you beat the game once or twice foreknowledge is naturally a part of your game where you'll have a rough idea of the location of high danger area, meaning no reload required.

  • Current Underrail most effective tactic available (meta) strongly reward offense over defense. You want to kill everything as fast as possible. When presented w/ a choice between offense and defense, always go for offense. You want to hit as hard as possible while using minimal amount of resources, whether it's action point, movement point, psi point, ammo and what have you.

  • As of version, relatively harder build to play (translation: newbie unfriendly and therefore a frustrating experience for beginners), in order of increasing difficulty, are: melee, mechanical pistol and pure throwing.

  • Save often, save manually and use multiple saves. If you save every single time you level up in a new separate save you can roll back your character as there's no way to reset your abilities/skills/feats in this game.

  • Note you can start combat manually by pressing the [Enter] key. Similarly learn to end combat manually by pressing the [Enter] key when no enemies is within direct line of sight of you and you standing far enough away from any remaining enemy. Another way to end combat manually is to restealth against hostiles: you must incapacitate all enemies, move far enough away/stay out of line of sight of them, enter stealth mode and than end combat manually next turn by pressing [Enter]. You can also stay out of sight for a number of turns (around 5) until they stop chasing you, ending combat manually.

  • Be prepared for a bit of financial trouble early game. I would recommend an effective pickpocketing skill of 50 for new players and you'll never run out of meds and ammo.

  • Gun, melee, and crossbow, pick one single offensive skill and max it every level. You will fail miserably if you try to level more than one. Pure psi users can ignore all three completely. Throwing is a special case as you only need a very small investment for it to be effective.

  • Darkness range penalty: range precision takes a huge hit when attacking a target sitting in darkness. You can take advantage of this by ending your turn sitting in darkness. You can check yours and npc's darkness level by observing their portrait: right mouse click on any target will bring up their portrait listing their health and status effects. If you are using range attack, make sure to use night vision goggles and/or have source of light such as fire near your targets.

  • A few well-place bear traps and/or caltrops (both can be use with zero skill point investment) can significantly alter the flow of battle. There are three levels of fire burning on the ground, level 1 (incendiary grenade), level 2 (magnesium grenade) and level 3 (Napalm grenade). Enemies will usually attempt to go through level 1 fire in order to attack you but are generally reluctant to walk pass level 2+ fire on the ground.

  • Learn how noise attracts enemies: use this to misdirect enemies to stealth pass them, or lead them into your traps/kill zone prep w/ caltrops, gas grenades and bear traps. Example: use a vent to move to an empty spot, throw a grenade to make noise, and quickly hop back in the vent. While everyone on the level goes to check the noise, you pop out of a different vent to do your thing. Learn which weapon/attack is silent/make low level of noise and stuff that are LOUD and act accordingly. NPC will usually investigate the first noise they hear before moving to investigate a second, later noise, meaning you can split up enemies this way.

  • Divide and conquer. On maps with large amount of enemies, if possible, always try to take them out in small groups instead of fighting them all in one giant fight. For example: on a large map you can lure everyone to one corner using TNT. Attack small isolated group in a different area of the map killing them all within one ~ two turns, end combat manually, rise and repeat. Understanding of NPC AI (how they will always try to disarm discovered traps and gas grenade within sight) behavior are viable assets. Bear traps and caltrops can delay/stop enemy movements, splitting up enemies into smaller, more manageable groups.
General tips for new players part II
  • Understand NPC types, strengths and weaknesses will allow you to prioritized your attacks: your priorities are usually, in order starting from most dangerous to relatively harmless: Psi > Sniper/Crossbow > Grenadier > Range > melee with exceptions here and there depending on your build and gear. You'll eventually learn from experience and start hating on specific types of enemies ... *cough Death Stalker *cough.

  • Use crowd control: bear traps, caltrops (especially crawler poisoned type), incendiary (burning target to proc fear), toxic gas, flashbang, tasers, throwing nets, stun, acidic entanglement, etc. If you can CC an enemy standing right at the doorway/chokepoint and you are sitting inside a room/other side you are completely safe. You can also use fire on the ground (fire everywhere except a one tile wide clear path) to make NPC taking the long way around to attack you instead of a more direct/shorter path. Toxic gas grenade is exceptionally effective in increasing your damage against organic targets.

  • You don't need "cheese" to beat the game. sheepherder on the official forum for example already posted lots of dominating viable build with the self imposed restrictions on not using grenades, traps, caltrops and any weapons that doesn't fit the theme of his build. However this is only possible when you completely understand how Underrail works, which, by definition, is out of reach for a new player. For me personally, I don't mind "cheese" as the odds are always stack against you and there's nothing wrong using tools available. However using too much cheese is a pretty unfun experience and I try to play by using damage grenade as an opener and than use class specific weapons/attacks to finish up fights while using flashbang, bear traps, caltrops sparingly.

  • For your first quest, you can attack Rathound unmolested behind a closed fence. One area have a special design wall that will allow you to fight Rathounds one on one near the entrance. They are deathly afraid of fire, making incendiary weapons and even thrown flares very effective against them. The slightest sight of fire makes them scatter in fear, giving you a breather.

  • The two biggest drain of resources early game are ammo and repair kits. Don't sell melee (especially shock) weapons as you can recycle them into valuable mechanical and electronic repair kits.

  • You can get more money by repairing guns and armors before selling them, quicksave before repair and quickload if it's not worth it.

  • Junkyard is the hardest part of the game for everyone. Don't be discourage if mutant and mutated dog kicked your ass. This is usually because they use acidic attacks and a new player generally lacks acid resistance gears, so make sure to have Siphoner/Mutated Dog armor and footwear. If you are having trouble with Junkyard Depot A you can take a look at my Junkyard - Depot A walkthrough

  • Some creatures and some robots cannot open door. You can cheese a lot of fights by opening and closing a door + Premeditation/Adrenaline/Vitality Powder/Psycho-temporal Contraction.
    note: Animals and other low-intelligence enemies can now pass through curtain doors.

  • To detect traps, have one or a combination of the following:
    1. decent perception.
    2. decent traps skill.
    3. A good Motion Tracking Goggles can allow you to have good detection score despite having low PER and zero traps skills.

  • If you are having serious trouble with enemies using stun, consider taking Thick Skull or Locus of Control. Helmets crafted with Shaded Visor can protect against flashbangs.

  • Couple keyboard and mouse shortcuts to remember as you will use them a lot:
    "Enter" is the default key to manually start combat. You can also rebind this to some other key.
    Ctrl + C = copy current dialogue onto clipboard.
    Shift + click = activate item in place (such as fishing rod) without moving. Also useful to use when disarming traps so you won't accidentally click on the ground and walk into a trap.
    Looting screen
    Right mouse click on an item to instantly loot that item
    "a" key to loot all
    Crafting and Inventory screen
    Right mouse click on a loaded weapon to unload its ammo. Remember when you recycle a loaded gun you'll lose those ammo.
    Shift + click = split an item stack
    Ctrl + click on a weapon or armor = auto equip said weapon/armor
    Clicking on the crafting component square within the crafting screen will auto select the first available component; click again will select the next available component. Ctrl + click on the component within the inventory screen while having the crafting screen up will select the specific component.
    Alt + click on ground during turn based mode = move to grid ignoring nearby object(s).
    Pickpocketing screen
    Alt + click = pickpocket item

  • You have the ability to speed up the game while out of combat by:
    "+" key to Speed Up
    "-" key to Slow Down
    or you can click the lower left corner arrows

  • Use the in game speed adjuster and/or cheat engine for speed hack - this will vastly improve your Underrail experience. Want to walk even faster? Use Sprint outside of combat, wear high grade Infused Cave Hopper Leather armor or rathound regalia and high grade tabi or boot w/ boot spring.

  • Currency exchange - Colton in Junkyard is a ripoff, just exchange your SGS credit w/ Blaine/Jack Quicksilver/Old Jonas to Charons using normal trade at a 1:1 value ratio.

  • Currency exchange - Marty (Upper Underrail) and Marcus (Black Sea Expedition camp) both accept United Stations Dollar so you can exchange them to Charons using normal trade.

  • See Special equipment and tools, Expedition Leather armor section if you are looking for a hard counter against melee enemies such as Death Stalker and Lurker Assassin.

Against melee enemies
You are completely safe against a melee only enemy if you are far enough. I will list the minimum safety distance (1 = 1 tile away from you) for some common early game melee enemies:
Rathound = 7
Rathound Alpha = 7
Lurker Assassin = 9
Pig = 9
Warthog = 9
Siphoner = 6
Dog = 11

Mid game:
Bladeling = 3
Borer = 3

Fighting tactics vs. psi beetle
  • Only attack a psi beetle with an opened carapace. Top: closed carapace; bottom: opened carapace
  • Hide behind a wall or a corner to lure them in, they will most likely waste all their MP and AP so they can't attack. Chances are pretty high they'll open their carapace as well.
  • Always try to engage them in close quarters as this causes them to run away from you and waste action points they could use to attack you.
  • If you are fighting psi beetle in open space, don't attack a psi beetle with a closed carapace, walk toward it.
  • Incendiary/HE grenades are effective vs. psi beetle. Frag grenade also works on psi beetle w/ opened carapace.
A warning and recommendation to new players
I'm intentionally keeping this section vague in order to avoid spoiler.

You should make a new manual separate save when:

  1. Before you agree to start the gauntlet.
  2. If you are helping a certain protectore special squad and been told to meet them at a certain place after obtaining a certain item. Make sure you create a new save when you meet up with them.
  3. You finished talking to a certain faction leader and he told you he'll wait for you downstairs, make sure you save BEFORE you go down the elevator.
  4. OR in situation two - you are now inside an area protected by a huge mechanical gate (you can't miss this as the gate has its own cut-scene) and would like to start killing. Not so fast buddy, make sure you save BEFORE turning this faction hostile.
  5. Expedition: you are tasked with investigating all NFT facilities within the Black Sea. It would be in your best interest to make a new separate save BEFORE you enter any NFT facility.

There's a point of no return in the game with no warning and no autosave. If you have a manual save you can just load back, resupply and/or level up a bit more. Otherwise you'll be force to charge forward with limited supplies and no way to get back.
Game mechanic explained part I
Concept of effective skills and abilities
The image above shows Crossbows 135 (238). 135 is the actual skill point invested, or base, crossbow skill for this char. 238 is the effective crossbow skill. The chance to hit is calculated using the effective skill.

Any effective skill higher than the maximum base skill is not a waste. For example if you have crossbow 135 (238) - yes your max base skill is 135 (the game only allow you to invest a maximum of 135 skill points at this level), the 238 effective xbow skill is not a waste above 135. In fact, the damage and accuracy of your xbow is now calculated using only the effective value. The base value is pretty much ignored by the game except to check for feat requirement.
Don't confuse max base skill and max effective skill. They are two completely different thing.

TLDR: Base abilities + skills determine your effective skills - increasing and decreasing them depending on their respective values. Damage and accuracy calculations will only use effective skills and ignore base abilities and base skills. Important take from this is chance to hit calculations completely ignores respective effective/base abilities, in this case, PER. If you don't understand this, you wouldn't understand how the feat Versatility works.
Base skills and abilities are used for feat requirements and learning psi abilities.

If you really want to get into the nitty-gritty details, check out this thread for a discussion on skill cap, max base skill and max effective skill.

Why can't I hit anything?
  • Enemies' dodge and evasion reduce your accuracy.
  • Your offensive skill (gun/crossbow/melee) increases both damage and accuracy.
  • Darkness penalty - you will suffer a pretty large accuracy penalty using range weapon in the dark. Darkness penalty can be completely counteracted with Night Vision, or lowered with flares, fire and/or other ambient light sources such as Telekinetic Proxy.
  • Distance and optimal range - precision decreases with distance for all ranged weapons including AoE weapons. Precision further decreases beyond weapon's optimal range.
  • Low durability - any degraded weapon or heavily degraded weapon loses more precision the more degraded it is.
  • Move and Shoot penalty - crossbow, assault rifle and sniper rifle users will suffer accuracy penalty if you moved. This is why it's usually better to shoot before you move. Pistol and SMG users do not suffer from this move and shoot penalty. See the focused[stygiansoftware.com] article for more details.
  • Close Quarters penalty - crossbow and sniper rifle users will have a precision penalty against foes at melee range.
  • Strength requirement - assault rifles, sniper rifles and sledgehammers have a strength requirement. If the requirement is not met, precision is multiplied by current strength divided by required strength.
  • Other weapon modifiers - weapons may have attachments or other modifiers that change their base precision or burst precision.
  • There are various precision penalties while riding a jet ski. Generally for range char you want a jet ski with high stability; for melee char you want a jet ski with high maneuverability.
  • You are under status effect(s) reducing your precision such as Disruptive Field and Poison
  • Chance to hit is cap at 95%, so it's still possible to miss under ideal condition.

So in order to increase your accuracy, you should:
  • Pick one single offensive skill (gun/crossbow/melee) and max it every level. Don't try to save skill point by not maxing your main offensive skill unless you absolutely know what you are doing. It's usually not worth it due to the possibility of extra miss.
  • If possible, try to have a light source near your target. Flares are fine; Incendiary grenades are great for this. Night vision goggles is another option but it must be turn on in order to work and it drains battery like crazy.
  • Ensure your weapon is in good condition. Always carry a few repair kits for your weapons.
  • Try to shoot before you move when using a weapon with move and shoot penalty.
  • Melee enemies will use crippling strike on you causing a crippled status (strength decreased by 2). You can use Adrenaline Shot to increase your strength by 2 for 3 turns, or use Vitality Powder to increase your strength by 4 for 2 turns.

You can take a look at the precision[stygiansoftware.com] article on the official wiki for a more detailed explanation.

If you are really frustrated with accuracy in Underrail, an alternative would be playing as a psi character. In general, offensive psionic abilities cannot miss their targets. There are couple exceptions: Pyrokinesis and Cryokinetic Orb are AOE attack, so they can miss your target in the same way as grenade do, and some thought Control abilities can be resisted.

Armor resistance, threshold and penalty
In this screenshot you can see the insulated vest has a mechanical resistance of 19%, a mechanical threshold of 6 and an armor penalty of 10%.

When you take damage, the armor will either reduce it by the amount specified by the damage resistance or by the flat amount specified by the threshold, whichever is greater (not both). source[underrail.com]

Using the mechanical threshold and resistance from the screenshot above:
Any incoming mechanical damage from sources such as unarmed, melee weapons, bear traps, shrapnel from grenades, etc, at or below 6 will be completely blocked by the armor's mechanical threshold.

The line in green - "Mechanical damage threshold increased by 200% against bullets" is a special feature of tactical armor. In this case, this armor will completely block any incoming mechanical damage up to 18 (6 + 200%(6)) caused by bullets.

Some examples using numbers from this armor:

Incoming non-bullet mechanical damage of 20:
Damage after threshold reduction: 20 - 6 = 14
Damage after resistance reduction: 20 - (19% * 20) = 16.2
The game will use threshold reduction because it's greater, so you'll take 14 damage.

Incoming bullet mechanical damage of 20:
Damage after threshold reduction: 20 - 18 = 2
Damage after resistance reduction: 20 - (19% * 20) = 16.2
You'll take 2 damage.

Incoming mechanical damage of 100:
Damage after threshold reduction: 100 - 6 = 94
Damage after threshold reduction for bullets: 100 - 18 = 82
Damage after resistance reduction: 100 - (19% * 100) = 81
You'll take 81 damage.

Armor penalty reduces your Dodge, Evasion, Stealth skills and Movement Points by a percentage. You can check this by looking at your combat stats menu (hit the "C" key in game), defense tab.

For a more detailed explanation, see the official wiki article for armor[stygiansoftware.com].
Game mechanic explained part II
Action points (AP) and movement points (MP)
All characters have 50 AP. You will suffer a 15 AP penalty if you are wearing heavy armor without meeting its strength requirement. Once expired, the psi ability Psycho-temporal Contraction also has a chance for the target to be afflicted by the Psycho-temporal Dilation status with random duration and intensity. Fatigue is a debuff caused by ending Adrenaline Rush or Vitality Surge. Your base AP cannot be reduce below 35. For example, you are wearing heavy armor without meeting its STR requirement and you are under the effect of Psycho-temporal Dilation + Fatigue - your next turn will still start with 35 AP. AP can be temporarily increased by adrenaline shot (drug), vitality powder (drug), psycho-temporal contraction (psi ability), fatal throw (feat), blitz (feat), expert sprint (feat) and fight response (feat).

Character base MP equal 30 + extra 3 points for every point in agility above 5. MP can only be used for moving. MP are affected by agility, armor penalty or bonus, encumbrance and some feats. MP can be increased by some leather armor, crafted boots with boot springs, tabis, and various feats.

One turn equals 5 seconds.
Moving the distance of one tile costs 10 MP; Moving one tile diagonally costs 15 MP.

See this[stygiansoftware.com] official wiki article and https://www.stygiansoftware.com/wiki/index.php?title=Movement for more information.

Dexterity and AP cost reduction
Each point of DEX above 5 decreases AP cost by 3% for throwing knives, knives, combat gloves, pistols and SMGs. As of version, minimum AP cost for any attack is set to 4.
See Action point cost reduction table here[stygiansoftware.com].

Energy shield
Copy and paste from the combat stats article[stygiansoftware.com]:
Energy shields can absorb certain amounts of damage based on the damage's impact speed. Slower impact speeds are generally better against energy shields.

Shield Capacity is the total amount of damage the shield can absorb when fully charged.

All physical damage sources have an Impact Speed, which is one of the following:
  • Very Low — Melee attacks
  • Low — Slow projectiles (considerably slower than bullets, such as crossbow bolts and cryokinesis)
  • Medium — Bullets, shrapnel (from frag grenades/mines)
  • Fast — Explosives, extremely fast projectiles (such as those fired from sniper rifles)
  • Very Fast — Lasers, plasma, electrical attacks
Additionally, most light melee attacks will ignore certain amount of shield.
  • 60% — Typical knives
  • 80% — Typical fist weapons
  • 100% — Unarmed
You should pick a shield frequency against the type of attack you are having the most trouble with. Wearing tactical vest and melee enemies are giving you trouble? Wear a low frequency shield. Wearing metal armor and sniper still one shot you using aimed shot? Wear a high frequency shield. The "best" shield will depends on your build and enemy types. Keep in mind energy shields are weak against melee attacks and players should find other means of defense against them.
As always, consult the official wiki for a more detailed explanation on shield emitters[stygiansoftware.com].

Version 1.0.3 introduced a new mechanic - it now cost AP to retreat (area transition):
= 0AP on easy
= 25AP on normal
= 40AP on hard
= 40AP on dominating
When returning to an area after fleeing it during combat, your initiative penalty will be -1000, ensuring you'll never get to take your turn first.

Zone Control
Placed a trap near NPC and the entire area turned hostile? Killed a hobo in isolation and somehow the entire city knows and turned hostile? You need to understand zone control[stygiansoftware.com].

Weapon and psi noise level

Exporting/Importing characters
Export - save your current char (abilities, feats, exp, and your current inventory). This will not wipe/affect your current char in any way.
Import - use your exported char in a new game. This is not a new game+ so you won't gain any extra ability/skill points compare to a fresh char. Remember to skip the tutorial to keep your inventory.
You cannot export your character while riding a vehicle.

Game speed
Originally posted by Version patch note:
Added the ability to speed up the game while out of combat
"+" key to Speed Up
"-" key to Slow Down
or you can click the lower left corner arrows
Game mechanic explained part III
Merchant inventory will reset every ninety (90) real life, not in game, minutes when you are outside their zone. You can speed this up by using the in game speed adjustment and/or Cheat Engine. Merchants will upgrade their stock and start offering higher quality merchandise/crafting components two times. First one happens after you complete quest in Depot A, second on after completing oligarch quest-line. Not every shop is affected by this. source[stygiansoftware.com]
Based on my own experience and comments from other players on the official forum, as of version 1.0.3, special merchandise tier (unlocked using mercantile) seems to spawn higher quality crafting components.

How to use night vision goggles
Wear night vision goggles, making sure they are charged - drag goggles from inventory to quick action bar - use the quick action bar to turn it on and off.

Juggernaut and Nimble
Juggernaut checks the armor penalty of your Armor Suit itself and doesn't take into account your effective armor penalty. It also ignore armor penalty from helmet, suit and boots. Nimble doesn't affect it at all. source

Last Stand
Is your health reset to 1hp at the beginning of your turn (meaning you can inject an health hypo), or at the end (meaning you're gonna get killed if an enemy remains)?
At the end - there will be a period where you are at 1 HP and enemies get to attack you before you start your turn.

Special attack, with special attention to Burst
As of version 1.0.4, Unconditional special attack, meaning any special attack that does not have a cooldown or require special conditions to trigger no longer benefit from special attack damage bonus from Smart Module, Smart Goggles or other sources. Special bolts and on-hit effects from chemical pistols are not special attacks.
Unconditional special attack: burst, shotgun burst, heavy punch, and double shot. source[stygiansoftware.com]
Every bullet shots in burst have their own critical hit chance, which is why focus stim is godly.

You will now see which targets qualify for Ambush feat proc based on their and your current location. The indicator will be placed left of the target's health bar. source[stygiansoftware.com]

epeli posted a detailed explanation on ambush here[stygiansoftware.com]. In my own experience Incendiary grenades is the only reliable way to trigger ambush. Flare is really a hit and miss, especially with zero or low throwing skill, and glow from Mindshroom doesn't seem to work at all. The attacker (you) must remain in complete darkness, as any ambient light ruins the chances of an ambush attack.

Next we have to understand and properly setup ambush. You can check your character's light level by studying your portrait. There are actually 5 different light levels:
Level 0 = completely darkness, portrait is completely dark
Level 1 = a little bit of light, portrait will flickering between darkness and light
Level 2 = some light, portrait will flickering between darkness (short time) and light (long time)
Level 3 = almost full light, portrait will occasionally dim but will stay bright most of the time
Level 4 = full light, portrait stay bright all the time

Ambush will only work if your char is at light level 0 ~ 1. It's actually very easy to confuse light level 1 with level 2 so to be safe always try to shoot from light level 0.

Similarly you can check your enemies' light level by right mouse click on them and looking at their portrait.

Next - the best way to light up your enemies is incendiary grenades. You will need a high effective throwing skill because you want the fire and light to land exactly the way you want it. Once thrown you'll get this:

G = grenade landing spot
H = burning tile
E = empty space, nothing is happening


Burning tile will give off level 4 light up to 2 tiles away. You'll get another two tiles surrounding the area w/ various level of light (level 3 ~ 1), and than finally complete darkness. You should throw an incendiary grenade in turn base mode and learn its light locations.

If for some reason your incendiary grenade failed to light up your target you can try again on the same turn using a flare. Again you should throw a flare in turn based mode and study its light locations.

Dodge and evasion bonus from tabi boots/boots
Their dodge and evasion bonus will not show up on your skill screen but will be listed in your combat status. It's a feature not a bug! source[stygiansoftware.com] source[stygiansoftware.com]

Electrokinetic Imprint
Npc required a detection level of 125% of your effective Psychokinesis skill in order to detect your electrokinetic imprint. source

Bear trap
Bear trap critical chance is 5% and there's no way to increase it. source

Recklessness and Survival Instincts
You cannot increase critical chance for throwing knives and grenades by Recklessness and Survival Instincts. source[stygiansoftware.com].

Custom portraits
Underrail supports custom player portraits. source[stygiansoftware.com] Check out this thread[stygiansoftware.com] for some quality custom portraits.
You can also get realistic portrait pack by SEAJAR on GOG Underrail forum here[www.gog.com].
Skill check thresholds part I
Here are some effective skill thresholds, anything above would be a waste:
(E) = expansion only
Gear might have base ability requirement (i.e.: 8 STR), you will still be able to wield/wear the gear and enjoy the gear's bonus even if you do not meet the base ability requirement (at a cost of accuracy penalty for weapons; -15 AP max penalty for armor). The only exception to this is Hypno goggles: you can't wear it unless you have 5 WIL or higher.
Drugs will usually have a short duration, see respective in game pop up for details.
Food will usually last 20 min at slowest game speed, see respective in game pop up for details. Consuming food will remove effects of previous meals.

Throwing = depends on build, suggested effective throwing: 80
30 *BASE skill* for Grenadier
50 *BASE skill* for Three-Pointer
80 effective throwing is a good target to aim for as it will allow you to throw a grenade four tiles away at 90% accuracy. For some specialize builds (i.e.: energy pistol build heavily relying incendiary grenade to setup ambush/throwing only build) a higher throwing works wonders. However don't over invest in throwing as it does not increase damage of grenades.
~224 effective throwing for max grenade hit chance.
note: AoE attacks such as grenades have a hit chance cap of 90%.

Hacking = 130/135
Highest *computer hacking* check to reboot IRIS = 130
Highest hacking check in final area = 130
Highest hacking check in the game = 135 (to open a box containing a high quality Plasma Core) but it's sort of pointless as you get this after you defeated the final boss.
note: remember you can use hacking tools to increase your effective hacking when hacking containers. The best hacking tools is Huxkey (+15 hacking).
  • (Gear)(E) Lemurian Engineer Suit +10 hacking.
  • (Drug) Hypercerebrix +2 INT.
  • (Food) Under Pie +3 to all skills.
*note*: you can not use hacking tools when hacking a computer.

Lockpicking = 130
Open every ventilation shaft in the base game using omni-tool = 50[stygiansoftware.com]
Force open every ventilation shaft in the base game using crowbar = 8 STR[stygiansoftware.com]
*Please note the two preceding Underrail wiki links contain spoilers*
Highest lockpicking check = 130
  • (Tool) Huxkey +15 lockpicking.
  • (Gear) Jackknife +7 lockpicking.
  • (Gear) JKK Tactful Jacket provides +10 lockpicking. JKK exclusive gear.
  • (Gear)(E) Lemurian Engineer Suit +10 lockpicking.
  • (Food) Eel Sandwich +1 DEX.
  • (Food) Under Pie +3 to all skills.

Pickpocketing = 145 ~ 165
Suggested effective Pickpocketing for new players = 50, free ammo + medicine such as health hypo and adrenaline right from the beginning area (SGS + Junkyard)
32 = minimum value to steal All-in
80 = minimum value to steal Strange Medallion
91 = steal Unknown Insignia/Spectre Insignia
116 = steal Database Access Card Level 2 (Abram)
120 = steal Database Access Card Level 3 (Azif)
Pickpocketing threshold will vary depending on the random generated loot on npc.
  • (Food) Eel Sandwich +1 DEX.
  • (Food) Under Pie +3 to all skills.
  • (Food) Sleight of the Night +15 pickpocketing.

Traps = 95/165/185
You need 95 effective traps to arm HE Mine Mk V. When disarming a trap, if your traps skill is 20 points above the trap disarming difficulty, or if the trap is your own, you receive it as an item.
Current highest tested traps check = 185, disarmed and recovered plasma mine at Arke. However I think having 185 effective traps is overkill. 95 effective traps (without any food/tool/gear boost) is good enough for a trapper char.
TL:DR: 95 to arm every type of traps in the game. 165 disarm every trap in the game. 185 disarm and recover every trap in the game.
  • (Gear) Jackknife +7 traps.
  • (Gear) Trapper's Belt increases traps skill by 15%.
  • (Gear)(E) Lemurian Engineer Suit +20 traps.
  • (Food) Eel Sandwich +1 DEX.
  • (Food) Under Pie +3 to all skills.

Chemistry = 151+ for Chemical pistol char, 112 for everyone else
20 to make toxic gas grenades - highly recommended if you are playing dominating difficulty.
31 to use infused mutant dog leather as a crafting component.
You need 112 chemistry to craft Frag/HE grenade Mk V. You need 112+ chemistry to craft high quality chemical pistol. Unless you are playing as a chemical pistol char, the chemistry threshold is 112.
  • (Drug) Hypercerebrix +2 INT.
  • (Food) Under Pie +3 to all skills.
Skill check thresholds part II
Biology = 130 for base game, 150 for expansion
You need 130 biology to craft Supersoldier Drug. Keep in mind you won't be able to access your workbenches in the final area.
You need 150 biology to use Heartbreak poison.
  • (Drug) Hypercerebrix +2 INT.
  • (Food) Under Pie +3 to all skills.

Persuasion = 110
You need 110 persuasion to convince IRIS it's pointless to continue fighting.
  • (Gear) Tchortist Noble Robe provides +1 Will.
  • (Gear) Praetorian Chestguard +5 persuasion. Praetorian Security exclusive gear.
  • (Gear) Praetorian Peacekeeper + 10 persuasion. Praetorian Security exclusive gear.
  • (Gear) Praetorian Caped Peacekeeper + 10 persuasion. Praetorian Security exclusive gear.
  • (Gear) Hypno Goggles provides at least +10 persuasion (+30 max). JKK exclusive gear; WIL 5 requirement.
  • (Gear) JKK Tactful Jacket provides +15 to persuasion. JKK exclusive gear.
  • (Gear)(E) Heartbreaker Serpent Skin leather armor provides +10 persuasion.
  • (Gear)(E) Heartbreaker Serpent Skin tabi/boots provides +10 persuasion.
  • (Food) Under Pie provides +3 to all skills.
  • (Food) White Dude +3 AGI, +15 to persuasion, -2 DEX, - 2 PER, -30 psi point regeneration.

Intimidation = 75 for base game, 100 for expansion
  • (Gear) Mutated Dog Leather Armor +5 intimidation.
  • (Gear) Mutated Dog Leather Tabi +5 intimidation.
  • (Gear) Balaclava +5 intimidation.
  • (Gear) Bullet Strap Belt +5 intimidation.
  • (Gear) Butcher's Cleaver +20 intimidation.
  • (Gear) Chemical Assault Unit Armor +10 intimidation.
  • (Gear) Tchortist Robe +20 intimidation.
  • (Gear) Tchortist Noble Robe provides +1 WIL.
  • (Gear) Praetorian Chestguard +5 intimidation. Praetorian Security exclusive gear.
  • (Gear) Praetorian Peacekeeper +10 intimidation. Praetorian Security exclusive gear.
  • (Gear) Praetorian Caped Peacekeeper +10 intimidation. Praetorian Security exclusive gear.
  • (Gear)(E) Shell Strap Belt +5 intimidation.
  • (Gear)(E) Gray Officer Armor +15 intimidation.
  • (Gear)(E) Sørmirbæren Knife +10 intimidation.
  • (Gear)(E) Sørmirbæren Sabre +10 intimidation.
  • (Gear)(E) Sørmirbæren Spear +10 intimidation.
  • (Gear)(E) Sørmirbæren Staff-spear +10 intimidation.
  • (Gear)(E) Sørmirbæren Spirit Staff E +15 intimidation.
  • (Gear)(E) Sørmirbæren Skærder Knife +20 intimidation.
  • (Gear)(E) Sørmirbæren Skærder Sword +20 intimidation.
  • (Gear)(E) Sørmirbæren Skærder Spear +20 intimidation.
  • (Gear)(E) Høddurform +20 intimidation.
  • (Gear)(E) Death's Grin +30 intimidation.
  • (Food) Under Pie provides +3 to all skills.

Mercantile = 105 for the base game, 140 for expansion
Mercantile will get you better quest rewards, lower trading prices, and is also used to unlock special merchandise tier on some merchants. 105 effective Mercantile will unlock all special merchandise tiers in the game; 140 effective Merchantile will allow you to pass the highest Mercantile check for a certain jetski vendor.
  • (Drug) Hypercerebrix +2 INT.
  • (Food) Under Pie +3 to all skills.

note: see this page[stygiansoftware.com] for details (*preceding link to Underrail wiki contains spoilers)

Based on experience and comments on the official forum special merchandise tiers appears to spawn higher quality components, see mindless' comment for details.

While not a skill check, it could be helpful for your char to stack initiative. From personal experience a 35 initiative char still lose checks occasionally. I'm guessing 50+ initiative will let you go first most of the time. Options are:
  • (Feat) Paranoia - +5 initiative (additional +1 ~ 5 by specialization).
  • (Feat) Trigger Happy - +7 initiative (additional +1 ~ 10 by specialization).
  • (Feat) Gunslinger - +7 initiative only when wielding gunpowder type pistol as active weapon (additional +1 ~ 5 by specialization).
  • (Gear) JKK Tactful Jacket - +5 initiative. JKK exclusive gear.
  • (Gear)(E) Infused Heartbreaker Serpent leather armor - +7 Initiative (-35 to stealth, -30 to evasion).
  • (Drug)(E) Twitch - +8 initiative.
  • (Food) Root Soda - +5 initiative.
Special equipment and tools part I
All food lasts 20 min. I'm only going to list food that I considered useful. Please note, when a food tool tips list x% of mechanical/heat/etc damage reduction this bonus is applied AFTER armor threshold/resistance just like Lifting belt and Conditioning.

Cave Hopper Steak - +1 AGI. You can pass a lot of agility checks by combining this food w/ Cave hopper tabi + Cave hopper leather armor for high AGI char.

Eel Sandwich - +1 DEX, very useful for DEX build, also increases skills in lockpicking, pickpocketing and traps. DEX melee char should use this over Hardcore chips even if you are playing a critical melee build.

Junkyard Surprise - +1/2 to random physical base ability, excluding PER, INT or WIL and -1/2 any random base ability. Not that useful in general but I just want to list this here in case you really need that one extra point of STR/AGI to pass a check.

Mushroom Brew - +1 STR, +10% mechanical damage reduction, -2 PER, -2 DEX, -20 to all psi skills, -1 psi point per turn. Obviously designed for Heavy armor AR/sledgehammer build, combine this w/ Lifting belt/Infused Ancient Rathound Gear/Conditioning/Stoicism for maximal effect.

Rathound Barbeque - +1 STR, increases your melee damage + accuracy and carrying capacity. STR melee build should have this buff on all the time. Other char using weapons w/ STR requirement might want to considering having this buff on most of the time to lessen the effect of being crippled.

Canned Mushrooms - 15% bio damage reduction, situational, probably the best canned food buff.

Hardcore Chips - Increases unarmed and weapon critical hit chance by 5%, but also increases the chance to get critically hit by 2%. Note this does not increase psi critical chance. This is a very useful food buff for char trying to stack their critical chance as high as possible. It's also exceptionally effective, when combined w/ Focus Stim, for build using Burst.

Mushroom Salad - +1 PER, useful for ranged char for the damage + accuracy bonus, as well as for detecting secrets when combined w/ other consumables such as Bioluminous Marsh Honey, The Juice and Third Eye.

Bioluminous Marsh Honey - +2 PER and +2HP/turn and makes consumer glow (set your own effective stealth to 0, also the glow can reveal stealthed targets such as Crawlers and Death Stalkers) for 10 turns, can't be crafted, natural loot drop found in the Black Sea (expansion). Its effect will stack on top of other food effect. It's highly recommended for you to consume Marsh Honey immediately if you suspect a stealthed enemy is nearby.

Pentapus Barbeque - +25 carrying capacity for lootaholic, combine this w/ Rathound Regalia (+10), Powerfist (+10), Lifting Belt (+30) and infused pig leather boots (+30) for maximum loot.

Pickled Mindshrooms - increases psionic critical damage bonus by 40%. Useful for crit psi build in some situation, great for short fights when you stack this together w/ Trance, crit psi headband and Spirit Staff. This food is relatively rare so buy it when you see this being offer by food vendors.

Psi Beetle Brain Soup - decreases psi ability psi cost by 15%. Super useful and highly recommended for all psi build (even more so than Pickled Mindshrooms) especially when combine w/ other psi cost reduction gears. This food is relatively rare so buy it when you see this being offer by food vendors.

Root Soda - +5 initiative, very useful for char w/ mid ~ high initiative.

Stuffed Bat - +15% detection, situational, always useful to have a couple in your inventory. Consume this + Third Eye and wear a high grade motion detection goggles for max detection.

Bison Milk - +1 STR, also increase critical damage bonus of melee weapons and unarmed attacks by 25%. Expansion only, only available by attacking the natives, excellent food for melee char.

Under Pie - +3 to all skills. The usefulness of this food requires no explanation.

The following consumables are available at Drag 'n' Drop, a random location, and as such, will not be present in all play-throughs and can appear in different places:
  • Waterways 5 - search the 5 Chancer's Bay maps starting from west/south of South Gate Station Docks
Starting at the Rig, the map with Murky the bartender
  • Rig Periphery, Waterways 12 - go 1 map NW
  • Core Ring Protectorate Outpost, Waterways 14 - Go 1 map NW, go 1 map west.
  • Core Ring, Waterways 29 - go 1 map north, go 1 map NE
See https://stygiansoftware.com/wiki/index.php?title=Drag_%27n%27_Drop for details.

All-in - +3 to all base abilities (!), but also increases chance to get critically hit with weapons, unnarmed attacks and psi abilities by 100% (additively). Known static location: at Drag 'n' Drop, "Dealer, Gambler and clubgoers event", inventory of Gambler standing opposite of dealer (32 effective pickpocket required).

Slampipe - +1 STR, +15% bonus damage with blunt melee weapons, fist weapons and unarmed attacks, but also reduces agility by 1.

Sleight of the Night - +15 to pickpocketing

White Dude - +3 AGI, +15 to persuasion, -2 DEX, - 2 PER, -30 psi point regeneration.

Perception - finding secrets
It's possible to find all secrets with a 3 PER char, making Snooping obsolete
(Base ability) 3 PER
(Gear) Adaptive Goggles +1 Perception
(Drug)(E) Third Eye E +3 Perception for the purpose of finding secrets
(Drug)(E) Bioluminous Marsh Honey +2 Perception
(Drug) The Juice +1 Perception
(Food) Mushroom Salad +1 Perception
For a total of 11 PER = finding all secrets except one, which require 12 PER. You can use:
(Drug) Supersoldier Drug +2 Perception, OR
(Food) All-in +3 all base abilities
Special equipment and tools part II
+2 INT, essential for crafting. If you are looking for the blueprint, see the Expansion section for details, expansion only.

Probably everyone's first unique. +7 to traps, +7 to lockpicking.

Lemurian Engineer Suit
+20 Traps, +10 Hacking, +10 Lockpicking, expansion only

Boxing Gloves
Pretty useless as a weapon but is an excellent source of buff (15% dodge) for brawler, psi monk and pure psi, just equip this in your off hand and switch to it before you end your turn. You can find one in Hecate Research Outpost.[stygiansoftware.com]

Expedition Leather armor
There are two different expedition leather armor sets that could offer melee immunity.

Styg did implemented a hard counter to Death Stalker since the introduction to expedition. Lot of players apparently did not fully explore all available options (there's a recent post on how boots are currently useless - absolutely not! Which is proven below.)

Infused Sea Wyrm Scales/Leper Serpent Skin leather armor + Infused Sea Wyrm Scales//Leper Serpent Skin boots. Using these very heavy armor set, at some point you'll become immune to knife attack, at top quality you'll be immune to melee attack. This have some interesting implications which will completely changed a lot of meta once you achieve that point.

These armor set is far from OP as they are:
very high in armor penalty - with all its associated con
still weak against sniper, xbow and psi even with top quality kelvar coat + top q shield
very hard to obtain without Skinner and/or tedious farming, oh man super steel farming alone on my current run was tedious as hell. Sea Wyrm rusting debuff is so ♥♥♥♥♥♥♥♥ annoying.

Siphoner: Headbutt will still proc stun even w/ zero damage; Siphoning attack will bypass melee immunity causing damage and heal the Siphoner.

*Spoilers below - you have been warned.*

There are many ways of locking yourselves out of getting this unique tool or unintentionally anger certain factions:
Info for Abram - lock out of the entire quest line if you did not answer "no dogs" and/or "Yes, I'm allowed to go back".
Abram's bug - Protectorate will turn hostile if you are caught planting the bug.
Free Maura - if you are spotted in prison and leave without killing everyone Protectorate will turn hostile. If you report Abram to Second Lieutenant Garren before you free Maura you will be lock out of the entire quest line. You are free to snitch on Abram AFTER you free Maura, but depending on how the conversation goes Protectorate might or might not turn hostile.
Everard's assignment - the obvious route would be breaking Todor out of prison but that's not the optimal solution. You need to convince Chief Banner Todor is innocence. If you don't have 85 persuasion you should tackle this quest AFTER you killed the beast.
Old man Nosek - the manor interior has "Leave No Witnesses" Zone Control rule. To be sure you won't get into trouble with guards later on, do as it says and leave no witnesses. Kill everyone inside the manor except old man Nosek. This is probably the fastest and easiest way to meet Nosek for a 0 lockpicking 0 hacking char. Note Praetorian Security will turn hostile if you attack the manor guards outside without provocation.

Tchortist Noble Robe
There is a way to obtain a Tchortist Noble Robe without turning the Institute of Tchort hostile. Just kill Minister Percival and every Tchortists in Core city upper level before the Research facility quest.

epeli posted an alternative way to get this robe late game without turning the Institute hostile, see here[rpgcodex.net].

*end of spoilers*

*end of spoilers*
Character build part I (outdated)

The controversial psi nerf is now officially the main branch as of Sep 7, 2020. For those that are firmly against this change, or maybe just want to finish their current cave wizard rampage, a separate Legacy branch (version is available. You can access the legacy branch by opening your steam library, right click on Underrail -> properties... -> click on "BETAS" tab at the top -> select legacy version.

Junkyard surprises no longer grant INT+2 buff as of version 1.0.3. Hypercerebrix grant INT+2 but it's DLC content. The (outdated) sections were written for version 1.0.2 but they should still work after you adjust crafting skills accordingly, factor in new feats + items and NOT playing dominating difficulty.

I'm slowly reworking the character build sections. Please remember these are my opinion, not fact. It's probably more fun to plan and build your own char so feel free to tweak a build to your liking.

Underrail is very min-max game. In general you can plan an optimized build as follow:
  • Use the build tool[underrail.info.tm]
  • Set level to 25, or 30 if you have DLC (remember to enable option: Expedition DLC)
  • Reduce all your abilities to 3
  • Plan out core feats for your build - adjust abilites and skills to meet their requirements
  • Max your primary offensive skill (gun/crossbow/melee/psi)
  • Adjust abilities and skills for your defense. In general heavy armor users need high str and should not invest in dodge/evasion/stealth. Light armor users need high agi, should max out evasion, heavily invest in stealth and adjust dodge skill according to needs. Remember dodge and evasion are all-or-nothing skills. However there are always exceptions.
  • It's possible, but not recommend to a new player, to finish the game with 0 lockpicking and hacking. Check out the skill threshold section as you do not want to over-invest in lockpicking and hacking. Remember there are tools that can boost your effective skills.
    Once you have some experience in Underrail you'll realize this is a fighting game and it's possible to finish every quest with 0 lockpicking and hacking. Personally I dump lockpicking and hacking in my games and play classic mode in order to maximize offense/defense/crafting.
    Things are a bit different in oddity mode as a lot of oddities are behind locks and inside hackable containers. It's still possible to reach level 25 in oddity mode without lockpicking and hacking but it's much slower, consider investing in pickpocketing to around eff. 100 to compensate.
  • Throwing is a special case as it can be your secondary source of damage and/or crowd control. It only need a very small investment in order to be effective. If you are a gambling boy/gal you can get away with 0 throwing by abusing the F9 key. You will need to test this yourself in game and find an acceptable skill level. Unless you are playing a throwing knives build, don't over-invest in this skill as grenade damage does not scale w/ your throwing skill.
  • Technology - crafting will get you the best gear in game. Crafted gear outclass unique by a mile. However, It's possible to finish the game with 0 crafting.
  • Social skills - there are more persuasion than intimidation checks so persuasion is the more useful skill of the two. Mercantile can now unlock special merchandise tiers offering higher quality crafting components.
  • Pump all remaining abilities points to the stat that will give bonus to your offensive skill: STR/DEX for melee, PER for gun & crossbow users, WIL for Psi and so on.

Guns - Pistol
Firearms + energy pistols - see here[underrail.com] for Wildan's build.
Chemical pistols - see here[underrail.com] for hilf's build.
Energy pistols only (viable for dominating difficulty) - http://underrail.com/forums/index.php?topic=3316.0
Comment: imho pistol build is one of the weaker class in Underrail.(*)(**) SMGs and Assault rifles are superior in every way.
Update: energy and chemical weapons receives some major buffs in version 1.0.3. Firearm pistol is now the second weakest class in the game.

Guns - SMG
Take a look at this link[underrail.com] for now.
Frog Friend/Firestalker proposed an alternative[underrail.com], and his SMG AP excel table is very useful - good work!
I used this[underrail.com] 0 lockpicking + 0 hacking SMG build and finished a hard classic game. I made some mistakes here: shouldn't have taken critical power as the extra 30% crit damage bonus on Steel Cat is not worth it. Doctor/Sprint/Interloper/Evasive Maneuvers would have been a better choice. All the skill points in pickpocketing should have went to dodge. See above link for a revised 0 lock 0 hack SMG build.
Update: Level progression and skill point allocation for my SMG build
Comment: a very strong class, consume bullets like crazy, a new player can try this as their first build. You should burst at close range, preferably point-blank, when using SMGs. You can duel wield SMG to cut down on reloading. Another option would be wielding a fast (5mm/7.62mm Jaguar) SMG on one hand and a slow, heavy hitting (8.6 Steel Cat/Syg MPX/Tommy Gun loaded w/ .44 Explosive Round) SMG on the other and only fire the slow SMG w/ the free burst from Commando.
Character build part II (outdated)
Guns - Sniper
See here[underrail.com] for Wildan's build.
I cleared a hard game w/ a 0 lockpicking + 0 hacking psi sniper build like this[underrail.info]. Most advice in Wildan's thread still apply with a few differences: you will wield a Smart Rapid 7.62mm Jaguar SMG instead of an assault rifle and use premeditation for Thermodynamic Destabilization or Cryostasis after Snipe.

This[underrail.info] is the throwing build I used to beat the game: critical demolition expert w/ throwing knives finisher using quad plated super-steel armor.
Comment: most fights are over in 1 turn due to critical Frag grenade Mk V. You won't be able to finish the gauntlet because this build is VERY gear dependent. A high agi throwing knife ninja is possible but I've never played one. Throwing build is currently THE weakest class so it's not recommended for a new player.

Melee combat gloves user
See this thread[underrail.com] for Wildan's (psi monk)[underrail.com] and my own (crit brawler) build.
Alternative 0 lock 0 hack version[underrail.com]
Comment: This is my strongest underrail char: attacking with a Pneumatic Bladed Infused Ancient Rathound Leather Gloves (late game) 10 times(min)/14 times(max) per turn @74% crit chance (13% base + 16% infused rathound leather armor + 15% focus stim + 30% survival instinct) w/ 225% crit damage bonus. Finally there's what I call beast mode (on every single drug in the game) = 1k+ raw damage per pneumatic strike or 3k+ raw damage per critical pneumatic strike, see a more detailed explanation here. You can probably modify my crit brawler into a crit psi monk build like this. If you are playing on hard you (@30% health) are going from 141HP to 105HP but gain Premeditation and a lot of psi abilities.

Melee knifer
See this thread[underrail.com] for Wildan's build.
Comment: Assassin used to be OP as ♥♥♥♥ as 1AP knife attack was possible before the nerf. Now it's one of the weaker class (but still not as weak as chemical pistol/throwing knives build) so it's not recommended for a new player.

Melee sledgehammer
See this thread[underrail.com] for Wildan's build.
Comment: if you look further down the thread you can see TiChrome hammer + tabi + lifting belt is the best setup due to 3 attacks per turn.

Originally posted by carashi:
... Balor + lifting belt ... is a viable choice given a certain situation. My char had both of those sledgehammers and switched between them when needed. I mean, you have two weapon slots anyway, no need to choose either ... With 16 STR base, rathound barbeque and use of adrenaline (not only it's +20 AP, it's also +2 STR) it's already 19 STR, which means that penalty to accuracy is very small and overall damage increase compensates more than enough for this. It results in 3 turns of 3 attacks with Balor hammer. In most cases it's enough to decimate your opponents ... Let's say you have 76-151 electrical damage (and we use my mechanical damage). Tichrome has 356 dmg/hit if we assume 95% accuracy. Balor has 574 dmg/hit with 90% accuracy (-5% for 1 STR lacking). TiChrome deal only 62% of damage comparad to Balor. Which means that with 3 vs 4 hits balor has distinct advantage around 300 dmg. With 2 vs 3 they are closer due to another 10% accuracy hit.

Also, with Balor in both cases you have 10 AP free for either taser or consuming medicine, while TiChrome eats almost all your points. Power core in my experience lasts for 7-8 hits, then you need to waste 10 AP for reload to keep your damage output. With balor you also don't need tabi, which means you can have Super Steel striders for another 10% of mech and energy resist. I didn't incorporate these points into calculation, but they all give another slight advantage to Balor.

You should decide for yourselves if the higher damage output justify the lost of 1 hit per turn.

Hammer Wizard on the official forum also released the Ultimate hammer guide[underrail.com].
Shotgun + Crossbow Psi hybrid (outdated)
AGI 13 version:

A more conventional build w/ lockpicking and hacking:
This version gain a huge critical chance=damage buff from Survival Instinct compare to the AGI 13 version but you have to stay at or below 30% health for this bonus. Another feature of this version is Grenadier meaning one damage (Frag/HE, usually Frag) nade per turn for the first two turn if you use LTI. Ideally you should scout the area under stealth to get a rough idea of terrain layout and enemies' location before manually starting combat. Abuse line of sight, hide behind doors/corner/force field and make enemies come to you instead of straight charging in. MP is much lower so make sure you craft and use jumping bean along w/ sprint, PTC and high grade tabi. The last feat Psycho-temporal acceleration could be switch w/ Opportunist.

Why 5 STR and not 7 STR?
I'm not using shotgun burst and I'm not getting Full-auto. 5 STR so I could use Vindicator shotgun

Why 5 DEX and not 6 DEX for Grenadier?
I suppose you could lower PER to 12 and drop a feat of your choice to get Grenadier. This is personal preference really. While playing my build I rarely have the chance or the need to use the same type of grenade twice. The battle is already over before grenade cooldown come into play.

Why AGI at 13? What's the point?
You need every last bit of MP to shell everyone in the face. Expert Sprint = 10 extra AP which is always useful for either an extra shell or an extra psi CC or pop medicine at 10 AP since I'm using bolt Quiver.

Con 3? Die a lot? Reload often?
Not really, I do die quite a few time to Death Stalkers but I considered that a given. Sometimes I do die when I play just a bit too aggressively (avoidable if I played it safe but I'm impatient sometimes). But I played the game so many times I would say I'm a veteran player. I will admit this is a glass cannon and newbie unfriendly build. If you want to use my build for your first run please play at normal or below and be prepare to abuse the reload button.

Psi hybrid at WIL 3?
That's fine as most of the psi abilities are use for crowd control (CC) and not for damage. ThermoD gets the job done at WIL 3 with only 70 base Metathermics along with shotgun shell damage.

Vindicator shotgun (short barrel, forward grip)
note: long barrel offer less damage + higher precision + narrower spread angle, not worth it because precision is great when you shell someone in the face at near melee range even when using short barrel. A wider spread angle is not a bad thing because that means more enemies are now under your shotgun's cone of fire. Shotgun Tube Extension - not bad but not great. Shotgun Choke = bad due to the exact same reasons as long barrel. Forward grip = great for non-combat shotgun as it lower 5AP per shot
Not using combat shotgun?
I'll explain this in more details below.

Scoped Pneumatic Cyclon Crossbow
Bolt Quiver
Infused Rathound Leather armor (mid ~ end game +11% crit chance)
Seeker googles (mid ~ end game, +18% or more crit chance, depends on your luck on component RNG roll)
Infused cave hopper tabi

On Dominating the first 9 level or so is a struggle because I couldn't afford a shotgun. For early game, Temporal distortion/grenade/SMG single shot will be your main damage output. This build really starts to get strong once you have enough money for a proper shotgun + ammo. At mid ~ late game it'll be one shot - one kill/multiple kills.

Why versatility? Why Crossbow?
Versatility is most effective when you can combine chem pistols w/ some other class (incendiary pistol for 2 turn fear, acid pistol for entanglement, Cooked shot ignore evasion and is AOE). However, my build doesn't have enough ability points for DEX to use chem pistols effectively. Crossbow is a great secondary long range weapon w/ shotgun for 1 turn stun using spammable Shock bolt (MKIII). Tranquilizer darts & Incendiary bolt seems great on paper but in my experience the long cooldown for TranQ and burning for Incendiary doesn't proc often enough to justify the lost utility slots.
I took 15 base Crossbow skill for Marksman. Around mid game I was able to fire my crossbow @14 AP (Scoped Pneumatic Cyclon Crossbow, bolt quiver) - you don't really care about crossbow damage; you just want the special bolt to hit using as little AP as possible.
TL;DR - Shotgun is your main damage dealer. Crossbow is there for on-demand no cooldown long range stun.

Why Kneecap shot?
Mostly for use around early ~ mid game when your shotgun shot isn't powerful enough yet for 1 shot = 1 kill without the powerup from Sixth Shot. Shock bolt + melee range Kneecap shot = 1 dead enemy standing. Late game you can use this to kite tough melee enemy (Balor, any sledgehammer npc using metal armor, Burrower warrior, etc.), allowing you to ignore them while you concentrate on other enemies.

Comments on Shotgun feats:
Sixth Shot is the most powerful shotgun feats, period. With max specialization your sixth shot now gain 200% BONUS damage on top of the original, usually critical damage

Why take Barrel Stare and Leading Shot together? Aren't they mutually exclusive?
No they are not. At least for my build it's not. Barrel Stare is to ensure a shotgun shell to the face at melee range is lethal. Leading Shot is use to deal w/ high evasion enemies and to help trigger ThermoD.

Why no burst feat like Full Auto?
You don't need to use burst. Combat Shotgun burst = 50AP and while it does delete enemies it's not really AP efficient. One single 20p Shotgun Shell shot from a Vindicator shotgun (short barrel, forward grip) is like a mini burst at mid range and only cost 20AP. Ideally you should reposition after every shot for optimal effect. At close to melee range one shell is usually enough to delete a single target provided you choose the correct shell loadout.
Shotgun + Crossbow Psi hybrid (outdated)
What's the correct shell loadout?
20p is the prefer shell choice because each individual pellet has its own chance to hit and crit. More pellet = more chance to hit/crit. Also Vindicator is the shotgun with the lowest min damage and highest max damage. More pellet = higher chance of at least one pellet reaching max damage. 20p is weak against heavily armor target (read: high mech resist, mech threshold is usually not a problem when you have high crit chance + bonus crit damage).

12p is my least favorite ammo as it fire less pellets than 20p while doesn't really offer any significant advantage.

6p is my prefer choice of ammo against heavily armor target because 1. you can buy this in bulk 2. It ignore 30% of mech damage resist which is usually good enough already. 3. it fires more pellet than 3p, see above on why more pellet = better.

3p does have its use but it's rare, expensive, and heavy. It can proc daze (1st shot), and stun (2nd shot on dazed target). You should use this against enemies w/ high mechanical resist such as Crabs, Strongmen and the final boss as it ignore 50% mech resist.

Math-wise you can see the damage difference too:
20p = 20 pellets * 6% shotgun damage = 120% shotgun damage
12p = 12 pellets * 9% shotgun damage = 108% shotgun damage
6p = 6 pellets * 15% shotgun damage = 90% shotgun damage
3p = 3 pellets * 25% shotgun damage = 75% shotgun damage
Of course this is only referencing the raw damage before mech threshold/resist calculation but it's also an important data point to consider.

As a side note my build can also use leper poison/corrosive acid bolt to lower a target's mech resist.

Fragmented Chaos - great, must have for all shotgun build along w/ Sixth Shot

Pellet Mayhem - very good feat because you must remember each pellets has its own individual chance to crit. When using 20p shell you'll notice your crit chance directly translate to number of pellets criting. This is also why Body horror is actually a good feat for 3 WIL shotgun build.

Perfect Scattering - absolutely useless in my opinion. Even at 2 points of damage using 20P shell that's only 40 extra damage. Worst case scenario: 3p, 1 points of damage per pellet = 3 extra damage. There are many other better feats out there. I would recommend avoiding it.

How to use:
I have around 47% critical chance (from gear) starting from mid game without using any food or drugs. Hardcore chip +5% crit chance. Body horror +3% crit chance. Focus stim +15% crit chance. Total crit chance = 70% + (3% ~ 12% from pellet mayhem). My first shell to the face using 20p usually deal around 400 damage (after mech threshold/resist/miss calculations) to a target. Once Six Shell buff is up I have seen as high as 1.7k damage. You see a crowd, thermoD, stand 4 tiles away from the target (with 3 tile of empty space between you and the target. You can check and see you need 30MP to move and stand besides the target). 1 or 2 shotgun shells should blow up the target. Follow up w/ grenade if required. This build has ♥♥♥♥ load of psi CC options so you do need to watch out and manage your psi pool. Stasis + Force Field are your panic buttons. Abuse line of sight. You can trigger a mini burst per shell when you stand 1 tile away from your closest target but you'll lose the barrel stare bonus. For some fights such as elevator fight, Aegis defense against native/pirate it's better to hang back and just spam shock bolt from the rear. Imho this build is pretty strong and perform the same, if not better, than my 5AP per punch psi-monk build. Only my pure psi builds are undeniably stronger than this build.
Guns - Assault Rifle part I
Horvatii from RPG Codex tell it like it is ...

One of the most powerful weapons in the game is the assault rifle, hereafter referred to as AR. While it can be use to single fire, its true power comes from burst fire. AR build will struggle a bit in the early game but once you have the right feats and gear setup it’s pretty much unstoppable due to W2C ammo. Just burst in the general direction of your enemies and mow them down like hay with combine harvesters. It’s simple, deadly and efficient, with the most common complaint about them being boring.

Overall class ranking
(Top > Middle > Bottom; Newbie friendly > Manual required > Newbie unfriendly)
Top class; Newbie friendly.

  • High damage output, due to W2C ammo nothing in the game can really tank against it.
  • easy to use.

  • STR requirement of 6 ~ 7. It’s possible to have your AR accuracy dropped to the minimum 10% by enemies using crippling strike.
  • Costly as you will fire a lot of bullets, maybe not as much as SMG build but still a lot. This means a really rough start at higher difficulty: getting your first AR is expensive, buying ammo is expensive, running out of ammo is a very real possibility if you are not careful.
  • AR durability will skydive when using burst. Repair kits are heavy. Keeping your ARs in top condition can be expensive and/or annoying due to the frequent return to base for ammo top up/repair/loot selling/stocking up on W2C ammo.
  • Boring.

The basics
AR is a burst weapon. While it can be use to single fire, due to the lack of single fire supporting feats I would not use AR exclusively as a single fire weapon. A single fire only AR build can be done but it will never match the power of a burst AR build.

To understand AR you need to understand burst. All player character can burst using AR, SMG and Combat Shotgun, no stat/feat required. Burst is an unconditional special attack, meaning it’s a special attack that does not have a cooldown or require special conditions to trigger. As of version 1.0.4, special attack damage bonus from Smart Module, Smart Goggles or other sources no longer works with unconditional special attacks.

Burst rapidly fires five bullets with reduced precision at a cost of 300% of active weapons Action Point cost, this has serious implication on AR optional enhancement selections. Burst fire has a chance to miss the primary target, possibly hitting other characters in the line of fire (generally considered as a cone shape with melee range being the pointy end) instead. Each bullet within a burst have their own individual chance to critical hit, meaning hardcore chips and focus stim are exceptionally effective when using AR.

Starting combat from real-time mode with Burst will fire only one shot. This is a known issue that's not easily fixable. As a workaround, enter turn-based mode using the [Enter] key first.

Core skills
  • Guns: max it every level! Unless you are building a STR melee versatility AR build which is outside the scope of this guide.
  • Mechanics: max at 173 effective to craft AR. You could lower this to your own optimal value if you are not planning on crafting AR in/after the final area.
  • Electronics: minimum 30 effective to use High Resolution Digital Scope. You will probably want this much higher in order to craft your own shield/seeker goggles/EMP grenade MKIII.
  • Biology: not essential but *highly recommended* to be at least 50 effective to craft Focus stim, or 70 effective to craft Hypercerebrix.
  • Tailoring: max at 179 effective to craft various infused leather armors from expedition; this will make your life in the Black Sea much easier. You could lower this to your own optimal value if you don’t have expedition.
  • Mercantile: not essential but *highly recommended* to be at 105 effective in order to increase the chance of getting high quality crafting components by unlocking all special merchandise tiers from available vendors.

Core feats
  • Suppressive fire
    requirement: level 1, PER 6, Guns 10
    reason for inclusion: +15% burst damage when combined w/ Opportunist.
  • Opportunist
    requirement: level 1
    reason for inclusion: +15% burst damage when combined w/ slow from Suppressive fire.
  • Full-auto
    requirement: level 6, STR 7, Guns 40
    reason for inclusion: extra 2 bullets per burst = 2/5 * 100% or 2/7 * 100% when using muzzled AR = at least 28.5 ~ 40% extra damage in addition to 2 more chance to critical hit.
  • Concentrated fire
    requirement: level 10, PER 8, Guns 60
    reason for inclusion: additional 10 ~ 100% extra burst damage; 30 ~ 300% extra burst damage when you invest 10 specialization points on it.
  • Commando
    requirement: level 14, Guns 80
    reason for inclusion: extra *FREE* burst when you killed an opponent using AR, in addition you can get 3 ~ 9 action points with the investment of 1 ~ 3 specialization points.

STAT allocation
So based on AR requirements and core feats the absolute minimum STAT allocation for an AR build is:

PER combined with your base Guns skill will determine your effective Guns skill, which in turn will determine your accuracy and weapons damage. 10 PER is considered low, 14 PER being average and 18 PER being the max, some numbers at max skills and level 30 for comparison:
18 PER = 350 effective Guns, weapon damage = 345% <- got this number from mouse over guns in Underrail.info builder
14 PER = 296 effective Guns, weapon damage = 307%
10 PER = 241 effective Guns, weapon damage = 269%

Known viable AR build variants
Heavy metal armor AR aka tin can AR – use quad plate Tungsten or Super Steel Metal armor set for 95% mechanical and/or energy resistance. Shaded metal helmet = immune to flashbang so frag/HE grenade and flashbang at your feet is a viable tactic for this type of build, can facetank almost everything excluding expedition content. You can go psi hybrid for Psycho-temporal Contraction (from Temporal Manuipulation psi school, expedition only) as the 30 movement points bonus ignores armor penalty, as well as Stasis for defense/offense. You will need high tailoring to craft specific heavy armors against specific enemies (ex: infused heartbreaker serpent skin leather set for expedition) which mean this type of build is no longer newbie friendly.

STR 8 for super steel metal armor or 9 for tungsten metal armor
DEX 3 or 6 for Grenadier
AGI 3 (no point in being higher than 3 as your high armor penalty heavily devalue the benefit from extra AGI)
CON 3 or 7 for Juggernaut or 9 for Survival Instinct/Last Stand or 10 for Thick Skull
PER 8+
INT 3 or 6 for Premeditation for psi hybrid or 7 for Gun Nuts/Power Management

Level 30: STR 8/9 DEX 3/6 AGI 3 CON 3/7/9/10 PER as high as possible WIL 3 INT 3/6/7
Guns - Assault Rifle part II
High mobility critical AR build – stack critical chance as high as you can by wearing Seeker googles, Infused rathound leather armor, tabi for MP bonus, Recklessness, Scrutinous, Body Horror, High Resolution Digital Scope in AR, Focus stim, and Hardcore chip. Objective is not to tank but use your high mobility to hide behind obstacle/corner to not get hit. If that’s not possible, run away as far as you can at the end of turn to minimize enemies’ hit chance/deny melee enemies’ attack. May include max dodge/evasion as additional layer of defense. Stealth, Ambush, Psycho-temporal Contraction, Stasis, incendiary 8.6mm ammo and incendiary grenades are valuable assets.

STR 7 for Full-auto
DEX 3 or 6 for Grenadier
AGI 6 for Sprint or 7 for Hit and Run/Flight Response/Interloper or 8 for Uncanny dodge or 10 for Blitz
PER 8+
INT 3 or 6 for Premeditation for psi hybrid or 7 for Gun Nuts/Power Management

Level 30 STR 7 DEX 3/6 AGI 6/7/8/10 or 13 for Expert Sprint CON 3 PER as high as possible, but min 11 for Scrutinous WIL 3 INT 3/6/7

Specialization recommendation
  • [Get this first] 3 specialization points on Commando for 9 Action Point refund once per turn when killing an opponent using AR.
  • 10 specialization points on Concentrated Fire as it increases damage bonus from 10 ~ 100% to 30 ~ 300%.

AR comparison
Base Action point (AP) is 50 for all characters, burst requires 300% of AR’s base AP to fire. Suppose your AR’s base AP is 12, your first burst will cost you 12AP(300%) = 36AP with 14AP remaining. Throwing a grenade requires 15 AP, now you are 1 AP short.

If you use an adrenaline shot you’ll be Fatigue (Action point decreased by 15) when adrenaline expired. If you are using an AR with a base AP cost of 12 you can’t burst when Fatigue.

If you use Psycho-temporal Contraction once its effect expires there is a chance for the target to be afflicted by the Psycho-temporal Dilation status with random duration and intensity (Action point decreased up to a max of 15). Once again if you are using an AR with a base AP cost of 12 you might not be able to burst.

Note your Base Action point per turn cannot be decrease below 35. For example, you are Fatigue and afflicted by Psycho-temporal Dilation, your base action point for this turn is still 35.

Due to the aforementioned reasons, it would be best to have your fast firing AR having a base AP of 11 or less. Muzzle Brake and Rapid Reloader (hereafter abv. as RR) are objectively the two best AR optional enhancements. Therefore, your choices are:

Marauder - RR 7.62mm
Huszar - none
Hornet - RR 7.62mm, 7.62mm, RR 8.6mm
Chimera – none

So you have one single choice for 8.6mm - Hornet
Rapid Muzzled 8.6mm Hornet(Q178)
Damage 26 - 57
Base action point: 10AP
Range: 14 (optimal: 10)
Move and shot precision: -5%
Burst precision +10%
Extra burst shot: 2
Critical chance: 5%
Critical damage bonus: 90%

Two choices for 7.62 - RR Marauder and Hornet w/ or w/o RR
Rapid Muzzled 7.62mm Marauder(Q181)
Damage 25 - 57
Base action point: 11AP
Range: 14 (optimal: 10)
Move and shot precision: -5%
Extra burst shot: 2
Critical chance: 5%
Critical damage bonus: 100%

As you can see Rapid Muzzled 8.6mm Hornet (10% more accurate burst) are more or less equal in power to Rapid Muzzled 7.62 Marauder (10% more critical damage bonus per shot). In my mind the Rapid Muzzled 8.6mm Hornet have a slight advantage of having a lower base AP cost and the ability to use incendiary 8.6mm ammo.

Muzzled HRD Scoped 7.62mm Hornet(Q178)
Damage 26 - 47
Base action point: 11AP
Range: 14 (optimal: 10)
Move and shot precision: -5%
Burst precision +10%
Extra burst shot 2
Critical chance: 12%
Critical damage bonus: 90%

A 7.62mm Hornet does not need a RR to have a base AP cost of 11 or less. Muzzled Scoped 7.62mm Hornet is in the unique position of having the option to use HRD scope for +7% critical chance or AA scope for +35% critical bonus damage to proc Critical Power. Your build will determine the last optional enhancements for your AR. If you already have high critical chance due to having Recknessless, Scrutinous, Body Horror, Infused rathound leather armor, Hardcore chips + Focus stim, it might be best to use Anatomically-Aware Scope (+35% Critical damage bonus) and get Critical Power to maximize your critical damage bonus. On the other hand, if you are just using Hardcore chips + Focus stim it’s better to use High Resolution Digital Scope (+7% Critical chance) to increase your critical chance:
AR base critical chance = 5% + Hardcore chips = 5% + Focus stim = 15% = 25% * 9 bullets (+2 Full Auto, +2 Muzzle brake) = 2.25 bullets critical hit.
25% + High Resolution Digital Scope = 7% = 32% * 9 bullets = 2.88 bullets critical hit (now it’s closer to 3 bullets vs. the 2 bullets critical hit per burst without HRD scope).

Rapid Muzzled 7.62mm Hornet(Q178)
Damage 26 - 47
Base action point: 9AP
Range: 14 (optimal: 10)
Move and shot precision: -5%
Burst precision +10%
Extra burst shot 2
Critical chance: 5%
Critical damage bonus: 90%

We'll need to do some math before declaring a winner for being the best fast AR.

The math
The maximum AP available would be base (50) + Psycho-temporal Contraction (15) + Adrenaline (20) or Vitality Powder (25). We are going to ignore Vitality Powder as it's not available until mid ~ late game. At full (3) specialization, Commando restore 9 AP (available at level 18) once per turn, therefore we now have 94 AP per turn.

RR has a 25% chance to restore 50%-100% (up to 10-20) AP on shoot, once per turn. The chance of RR not restoring any AP for a 5 round burst is 23.73%. The chance of RR not restoring any AP for a 9 round burst is 7.508%. 3 burst = 27 rounds and RR not restoring any AP now is a tiny 0.042%. Therefore, we'll assume RR will restore 50 ~ 100% of your AR's base AP once per turn.

We are now comparing the following three ARs:
Rapid Muzzled 8.6mm Hornet - Damage 26 - 57 - Base AP: 10 - Critical chance(CC): 5% - Critical damage bonus (CDB): 90%
Muzzled HRD Scoped 7.62mm Hornet - Damage 26 - 47 - Base AP: 11 - CC: 12% - CDB: 90%
Rapid Muzzled 7.62mm Hornet - Damage 26 - 47 - Base AP: 9 - CC: 5% - CDB: 90%

Assuming the worst case scenario, RR restore 50% base AP once per turn:
Rapid Muzzled 8.6mm Hornet = 5 AP restored = 99 AP per turn = 3 bursts + 1 free burst from Commando with 9 AP left over <- enough for 2 reload while wearing Bullet strap belt
Muzzled HRD Scoped 7.62mm Hornet = 0 AP restored = 94 AP per turn = 2 bursts + 1 free burst from Commando with 28 AP left over <- enough for 1 grenade with 13 AP left over = 3 reload while wearing Bullet strap belt or take 6 medicine while wearing Doctor's pouch
Rapid Muzzled 7.62mm Hornet = 4 AP restored = 97 AP per turn = 3 bursts + 1 free burst from Commando with 17 AP left over <- enough for 1 grenade or 5 reload while wearing Bullet Strap belt or take 8 medicine while wearing Doctor's pouch

TL:DR - we do not have a clear winner as the three AR all do different things:
Rapid Muzzled 8.6mm Hornet as your fast AR will output the highest burst damage. Personally I would choose this as my fast AR.
If your AR build already have high critical chance AND getting Critical power + Grenadiar AND able to craft at least Frag/HE MKIV, a Muzzled AA scoped 7.62mm Hornet would be your fast AR. The ability to proc Critical Power when using both slow and fast AR is invaluable.
Rapid Muzzled 7.62mm Hornet will do less burst damage than Rapid Muzzled 8.6mm Hornet but will get an extra grenade every turn. If you have good enough throwing and the ability to craft high tier grenades, this could the option for you.
Guns - Assault Rifle part III
Note: There are also other factors at play not used in the above calculations. Psycho-temporal Acceleration will grant you an extra 5 AP (or 7 AP when max specialized) when under PTC . RR could refund more than 50% of your guns base AP. Vitality Powder will grant you an extra 5 AP compare to Adrenaline Shot but last one turn shorter.

Commando grant you a free burst when you burst kill an opponent - you should take advantage of this by equipping a secondary AR w/ the highest damage potential (and disregard the base AP cost).

Two contenders:
Again, use HRD scope if you have low critical chance, use AA scope if you have high critical chance + Critical power
Muzzled Scoped 9mm Chimera(Q172)
Damage 27 - 64
Base action point cost: 16 AP
Range: 14 (optimal: 10)
Move and shot precision: -5%
Extra burst shot 2
Critical chance: 5% or 12% when using HRD scope
Critical damage bonus: 130% or 165% when using AA scope

Muzzled Scoped 9mm Huszar(Q161 <- a bit low but that's the highest Q I have available)
Damage 21 - 80
Base action point cost: 16 AP
Range: 14 (optimal: 10)
Move and shot precision: -5%
Burst precision: -5%
Extra burst shot 2
Critical chance: 7% or 14% when using HRD scope
Critical damage bonus: 100% or 135% when using AA scope
Note: Huszar is the only AR w/ a STR requirement of 7, all other AR req STR 6.

Imho, Chimera is the superior AR w/ the tighter spread, higher burst accuracy and higher critical damage bonus.

Conclusion: get a Muzzled Scoped 9mm Chimera as your secondary slow AR.

General Tactics
  • Similar to SMG, you can wield a fast AR on one hand and a slow, heavy hitting (9mm/Steyr-Auch) AR on the other and fire the slow AR w/ the free burst from Commando.
  • You can trigger Ambush by using incendiary grenade, incendiary 8.6mm ammo and Telekinetic proxy.
  • NPC using crippling strike is a problem. If you are crippled, try using flashbang/Vanishing Powder Grenade against them, run away/restealth. Another option would be to run away and block the path between NPC and yourself using incendiary grenade (at least level 2 fire, so magnesium nade or above) to wait out the crippled status. You can also temporary boost your STR by 2 using Adrenaline shot or by 4 using Vitality powder.
  • Standing in fire can prevent you from being Incapacitated/Frozen/Webbed.

Additional comments
  • Remember to buy all the W2C ammo when you shop.
  • Hardcore chips and focus stim are exceptionally effective with AR, stock up and use them.
  • EMP grenade MKIII stun robots for one additional turn compare to MKI/MKII.
  • Toxic gas grenade has its own separate cooldown from frag/HE/incendiary grenade and is a very effective crowd control early/mid game.
  • AR Enhancements:
    Early game - your effective gun skill is still relatively low and accuracy might be a problem. If that's the case, use:
    Scope, +6% precision, +2% critical chance
    Rifle Bipod, +10% precision, +2 base AP cost
    Barrel Compensator, +15% Burst precision
Recommended build for first time player - Koveras' Assault Rifle / Thought Control hybrid
Original post

Modified build
Removed Power management as its benefit is minimal and replaced it with Iron Will. Resolve is already high but once you have it at level 30 you can pretty much tank Neural Overload and Bilocation from NPC. Another alternative to Iron Will would be Ambush for help dealing w/ high evasion enemies; although it's not going to help you against Magnar since there's no dark spot available. Gun Nut/Psycho-temporal acceleration/Blindsiding/Fight response are also viable choices for this last feat slot.
  • Keeping Hacking because INT is high, increase effective value to threshold.
  • Removed Lockpicking due to 3 DEX <- this is a personal preference to save skill point, optional change.
  • Increase effective persuasion to threshold w/ help of gears, optional change.
  • Increase e.chemistry to 69 for MKIV grenades.
  • Increase e.bio for supersoldier drugs.
  • Increase Temporal to 70 for haste + stasis <- imho the most important change as Stasis is a good panic button.
  • Decrease e.merchantile to 105 to unlock all vendor special merchandise tiers.

You can take all skill points from persuasion + some points from stealth to reach lockpicking threshold. It's just with 3 DEX you are not really getting the best bang for your buck.
If you still need more skill points you can take points away from biology. Just remember you need 115 effective for regenerative mixture (no work bench, bring Hypercerebrix), 100 effective for Super Health Hypo, 95 effective for Third eye, 80 effective for Bullhead and the absolute minimum should be 70 effective (with work bench only) for Hypercerebrix.

I will defer to Koveras (Thanks! Great build Koveras!), the build's creator, for the build's roadmap:

note: originally I put some skill points in pickpocketing. Upon reflection, persuasion offer a much better value. You should start pushing mercantile first and persuasion next starting around level 16.

I no longer recommend the tin can AR build of old (Quad plated metal armor AR build) for first time players. Koveras' AR/TC hybrid is now my recommendation for newbie. The goal of this build isn't to tank everything while mowing everything down with your AR. You should have a lot of mobility wearing a sturdy psionic overcoat tact.vest (sturdy vest, laminated panel, psi beetle carapace, black cloth), psi headband, tabi/metal boots with Nimble + Psycho-temporal Contraction so make sure to take full advantage of it by always ending your turn hiding behind obstacle/corner to avoid getting hit. Unlike a regular tin car AR build, you are no longer hard counter by Neural Overload and Bilocation from NPC. Like Koveras said the TC part of the build mix thing up so things won't get boring as fast as tin car AR. Build should be viable on all difficulty; of course, a first time player should not attempt dominating difficulty.

For a different perspective and additional hand-holding, you can read:
Aether's Underrail Sniper & Assault Rifle Build Guide

HappyRBX's Assault Rifle & Sniper Guide for Beginners (needs Expedition DLC)

Crossbows part I
A shock bolt from nowhere stunned you in place while other enemies had their way with you while you can’t fight back. A few turns later, you found the crossbow wielding bastard was hitting you from more than one screen away, CC/poison you to oblivion with deadly accuracy, W! T! F! Yessss, hold this feeling of rage, pain and hate dear! Use them to sharpen the edge of your anger, and turn, to the DARK SI (*see bunch of Disney lawyers getting excited in the distance) … Ahem … Aaannyway … Wake the f*** Up Samurai, pick up your crossbow, it’s payback time. We’ll do the same thing to them, with interest.

Overall class ranking
(Top > Middle > Bottom; Newbie friendly > Manual required > Newbie unfriendly)
If you only have the base game, the ranking is:
Middle; Manual required.

Crossbow received some major buffs from expedition DLC. Crossbow can be top tier when build in a very specific way. However, there are numerous misleading feats and other pitfalls so its ranking is:
Top/Middle; Manual required.

  • Versatile due to the vast array of special bolts available.
  • Silent.
  • High range.

  • Inherent close quarters precision penalty so your accuracy takes a hit whenever there’s at least one enemy within your melee range.
  • Inherent move and shoot precision penalty, this can be completely migrated w/ Strafe.
  • Weak against enemies with high mechanical resistance. This is due to crossbow’s inherent 125% increased mechanical damage resistance penalty, as well as majority of crossbow damage being mechanical even when using special bolts.
  • Weak against critical immune enemies (thankfully, they are relatively rare in the game: Bladlings, Shrooming Chompers/Spitter and Spore Turret) due to heavy reliant on critical hit.

The basics
Crossbow is a mediocre weapon without expansion. Snipe (and its prerequisite Aimed shot), Kneecap Shot, Deadly Snares, Quick Tinkering and traps are essential components for a base game only crossbow build. Majority of Wildan’s comment on crossbow are still relevant for version

I revised Wildan’s build to include Bowyer:

Pack Rathound is a QoL feats that could be skipped if you are using cheat engine unlimited carrying weight hack. Kneecap Shot could be replaced by Uncanny dodge (take 40 skill points from Stealth and put them into Dodge) or Vile Weaponry or Grenadier (probably want to take it early) or Ambush.

There’s also a crossbow + chemical pistol hybrid taking advantage of Versatility, Acidic entanglement from Acid blob pistols and Deadly Snares:

However, all of the above are irrelevant/obsolete if you have the DLC. Crossbow is now a completely different animal:
Bolt Quiver reduces all crossbow attacks by 3 Action Points (AP) meaning the lowest possible AP is now 14 per shot instead of 17.
Strafe completely eliminates move and shoot precision penalty.
Psycho-temporal Contraction from Temporal Manipulation psi school now add 15 AP for 2 turns (or 20 to 22AP for 3 turns if you take the Psycho-temporal Acceleration feats and its specialization).
The Scrutinous veteran feat now makes a 100% critical chance crossbow build without Deadly Snares and/or Ambush possible.

I will list what I considered misleading feats below; They might seem like a good fit and/or useful when you should really avoid them:

Snipe – while it’s possible to use this feat w/ crossbow to dish out hefty raw damage, the fact you can only use regular bolt (translation: mechanical damage only, no CC/add-on damage from special bolt) w/ it makes this a bad crossbow feat.

Kneecap Shot – same as Snipe, you can only use this feat w/ regular bolt. While it’s nice to take away all movement points from NPC this debuff is not needed when you can just one/two shot everything using special bolt critical hit.

Deadly Snares/Ambush – two obsolete feats for crossbow build as 100% critical chance is obtainable without them. By skipping these two feats you no longer need to prep the battlefield w/ traps or worry about light level to proc Ambush. You also no longer have a weakness against enemies that are immune to immobilization such as Industrial Robots, Coil Spiders, Giant Creepers and Weavers.

Quick Tinkering – used to be a god tier feat, had a 2-turn cooldown and costed 0 AP to place down a trap. Styg nerfed it to the ground by increasing cooldown to 5 turns and cost to place down a trap to 25AP (could be reduced to 4 turns cooldown and 0AP cost by specialization, a waste of specialization points imho). This is now a bad feat in general and especially bad for crossbow build when we don’t need to proc Deadly Snares.

Concussive Shots – not really that great as it only works on organics. This feat is pretty much irrelevant once you’ll start one/two shot everything by mid to late game.

Traps – while useful they are no longer essential for crossbow build as you don’t need to proc Deadly Snares.

Sources of critical chance:
  • Based critical chance for Cyclon/Zephyr crossbow = 8%
  • Survival Instincts = 30%
  • Recklessness = 7%
  • Scrutinous = 7%
  • Hardcore chips = 5%
  • Focus Stims = 15%
  • Seeker Goggles = 19%
  • Infused Rathound leather armor = 10%
Total critical chance = (8 + 30 + 7 + 7 + 5 + 15 + 19 + 10) % = 101%

A top tier crossbow build will focus on getting the biggest alpha strike by manually starting combat from stealth while maximizing critical chance, critical damage bonus, accuracy, damage and number of shots per turn.

Core skills
  • Max Crossbow every level, no exception!
  • Stealth: at least 100 effective from skills alone as stealth is vital to all crossbow build; higher is better, this is the skill where you should dump all your extra skill points.
  • Mechanics: max at 150 effective to craft crossbows. You could lower this to your own optimal value if you are not planning on crafting crossbow in/after the final area
  • Electronics: 60 effective is the absolute minimum for Shock bolts MK III; 105 effective for EMP grenades and mines MK III; 167 effective to craft high quality night vision seeker goggles; max is 194 effective for perfect quality energy shield but its components are only available in/after the final area. Recommended effective electronics is somewhere between 167 to 194 effective.
  • Chemistry: 75 effective is the absolute minimum for top tier chemical bolts; you should aim for this value without the aid of workbench/food/drugs so you can craft chemical bolts in the field.
  • Biology: 50 effective is the absolute minimum for Focus Stims; 70 effective will get you Hypercerebrix which is vital for crafting; 80 effective will get you Bullhead; 100 effective will get you Super Health Hypo. 115 effective will get you Regenerative Mixture and 130 effective will get you Super Soldier Drugs without the aid of workbenches in the final area. Imho, 100 effective is good enough as Regenerative Mixture and Super Soldier Drugs are nice luxuries when you could afford the skill points: thus I recommend an effective biology of either 100 (with aid of Underpie, workbenches and Hypercerebrix) or 115/130 (with the aid of Underpie + Hypercerebrix).
  • Tailoring: 128 effective is the absolute minimum to use infused rathound leather; Max value is at 179 effective for various infused leather armors. I would recommend an effective tailoring value somewhere below 179, depending on the quality of components found in your run.
  • Temporal Manipulation: 55 BASE skill is the absolute minimum to get PTC, 70 BASE skill will get you Stasis which is a valuable offensive and defensive psi ability. I highly recommend you aim for 70 BASE skill.
Crossbows part II
Non-core skills but recommended:
  • **highly recommended** 105 effective mercantile to unlock all special merchandise tiers in order to increase your chance of obtaining high quality crafting components
  • 80 effective throwing for 90% THC grenade throw to 4 tiles away from you
  • 95 effective traps without any aid from gear/food/drugs to use majority of traps available
  • 45 BASE psychokinesis for Electrokinesis and Electrokinetic Imprint

Core feats
  • Marksman
    requirement: level 1, DEX 5, Crossbow 15
    reason for inclusion: remove additional action point cost when firing special bolts.
  • Survival Instinct
    requirement: level 1, CON 9
    reason for inclusion: 30% critical chance when under 30% health, required to obtain 100% critical chance.
  • Strafe
    requirement: level 1, DEX 5, AGI 5
    reason for inclusion: reduces move and shoot penalty by 15%, effectively eliminate move and shoot penalty.
  • Special Tactics
    requirement: level 8, INT 6, Crossbow 50
    reason for inclusion: One free special bolt hit per alpha strike, make sure to manually start combat by pressing [ENTER] first before using this skill, should be use with your heavy hitting Zephyr crossbow for maximum damage.
  • Bowyer
    requirement: level 4, INT 7, Mechanics 30
    reason for inclusion: +35% critical damage bonus on all crafted crossbow.
  • Recklessness
    requirement: level 1
    reason for inclusion: +7% critical chance, required to obtain 100% critical chance
  • Elemental Bolts
    requirement: level 13, Crossbow 75
    reason for inclusion: double your electrical, acid, and heat damage as soon as you get it. damage bonus can be further increase by investing in its specialization.
  • Critical Power
    requirement: level 13, Crossbow 75
    reason for inclusion: even with the latest nerf this feat is still essential to maximize critical damage bonus.
  • Sharpshooter (and its prerequisite Aimed Shot)
    requirement: level 10, PER 10, Crossbow 60
    reason for inclusion: +30% critical damage bonus when focused, needed to maximize critical damage bonus. If Aimed Shot isn’t the prerequisite for Sharpshooter, I would've drop it from the build in a heart beat.
  • Scrutinous
    requirement: level 26, PER 11, Crossbow 120
    reason for inclusion: +7% critical chance, required to obtain 100% critical chance

Non-core feats but recommended:
  • Grenadier
    requirement: level 4, DEX 6, Throwing 30
    reason for inclusion: It’s not possible to get 100% critical chance until mid to late game. Grenadier, combined with traps, caltrops will help you greatly during your early game. This feat is still useful mid to late game by reducing cooldown for Flashbangs and EMP grenades.
  • Premeditation
    requirement: level 6, INT 6, any psi skill 40, Psi Empathy
    reason for inclusion: one free cast of any psi ability every 5 turns, super useful to cast either Stasis or Electrokinesis
  • Blindsiding
    requirement: level 14, Stealth 80
    reason for inclusion: +15% damage while in stealth and one turn after exiting stealth. Extra damage = better alpha strike; you can extend Blindsiding buff by another turn using Stasis.
  • Increased Perception
    requirement: level 26
    reason for inclusion: high PER = higher effective crossbow skill = better accuracy + higher crossbow weapon damage
  • Opportunist
    requirement: level 1
    reason for inclusion: 25% extra damage against rooted, stunned, and incapacitated targets. This is a low priority and highly optional feat but nice to have against bosses. You should be able to easily trigger any one of the three required status effect against your targets.
  • Psycho-temporal acceleration
    requirement: level 7, temporal manipulation 45, Psi Empathy
    reason for inclusion: At 14AP per shot, you will only be able to get 4 shots (50 base AP + 15AP from PTC = 65 available, 56 AP used, leaving you with an awkward amount of 9 AP remaining) without the use of adrenaline shot. If you get this feat you will get exactly 5 shots (50 base AP + 20AP from PTC = 70 available, 70 used) without adrenaline. Another low priority and highly optional feat but it’s nice to get another extra shot in your alpha strike without worrying about being fatigued from adrenaline. Imho Opportunist offer slightly better value than this feat for crossbow users.
  • Blitz would have been a great fit for any crossbow build but it’s just impossible to find enough STAT points for it in a SI crossbow build.
  • Quick Pockets – could be useful as crossbow users are always hopelessly starve for combat utility slot, swap with either Opportunist or Psycho-temporal acceleration if you want it.

STAT allocation
Based on crossbow requirements and core feats the absolute minimum STAT allocation for a crossbow build is:
STR 3 DEX 5 AGI 5 CON 9 PER 11 WIL 3 INT 7

If you absolutely need some STAT points for some reason to get some other feats you can take STAT points from PER. However, keep in mind PER combined with your base Crossbows skill will determine your effective Crossbows skill, which in turn will determine your accuracy and weapons damage. 10 PER is considered low, 14 PER being average and 18 PER being the max, some numbers at max skills and level 30 for comparison:
18 PER = 350 effective Crossbows, weapon damage = 345% <- got this number from mouse over crossbows in Underrail.info builder
14 PER = 296 effective Crossbows, weapon damage = 307%
10 PER = 241 effective Crossbows, weapon damage = 269%

Known viable build variants
High mobility Blitz crossbow
Instead of going for 9 CON for Survival Instincts (SI) you can take those STAT points to AGI for Blitz. However, you will need 60 movement points in order to gain the maximum 20 extra AP from Blitz which is hard to do when you are attacking from Stealth. You will need to take other feats (such as Sprint, Interloper, Hit and Run, etc.) to gain movement points coming out of Stealth. Another route would be to forgo starting your alpha strike from stealth and opt for high initiative instead. The lost of guarantee critical hit can be migrated by taking Deadly Snares and/or Ambush but again that’s another extra one or two feat slots lost. High AGI means your dodge and evasion skills are much, much more effective; your exceptionally high movement points means you can simply outrun your enemies (when done right, melee enemies can’t even touch you; ranged enemies have reduced accuracy against you due to evasion and you standing outside their weapons’ optimal range). This type of build trade damage output for survivability. You also gain an additional 20 AP per alpha strike and another additional 10 AP by taking Expert Sprint (very costly at AGI 13). Cost benefit analysis dictates this variant is objectively inferior to the SI version, why dodge, evade and run away when you can kill everything before they get a chance to attack?

DEX 5 for Strafe or 6 for Grenadier or 7 for Three-Pointer
AGI 10 for Blitz
PER 10 for Sharpshooter and/or Deadly Snares
INT 7 for Bowyer
*note: you won’t have enough STAT point at level 1 for both 10 AGI and 10 PER, you will have to use the extra STAT point gain every fourth level to meet feat requirement.

Level 30: STR 3 DEX 5/6/7 AGI 10/13 for Expert Sprint CON 3 PER as high as possible WIL 3 INT 7
Crossbows part III
Psi Crossbow with heavy emphasis on psi - instead of going for 9 CON for SI you can take those STAT points to WIL for Locus of Control for stun, fear, incapacitation and mind control immunity. You do have a lot of options here: You can get 70 base Temporal Manipulation, max out Thought Control, go Psychosis + Psionic mania route for silent and deadly Neural Overload. Crossbow can cover your weakness against robots.

You can get 70 base Temporal Manipulation, max out Metathermics, go Tranquility + Thermodynamicity + grenadier. You start most fight using Aimed Shot to trigger Thermodynamic Destabilization (now capped at 100% of target’s health, which can be reach at 140 effective Metathermics. This psi ability cannot critical hit), throw a high tier frag/HE/Plasma grenade and mop up the rest using either crossbow and/or Metathermics.

You can get 70 base Temporal Manipulation, max out Psychokinesis, go Tranquility or Psychosis/Psionic mania route + Ambush and trigger Ambush using light from Telekinetic Proxy. You cover your weakness against high mechanical resist targets with Telekinetic Proxy + Implosion. Telekinetic Proxy + Telekinetic Punch is another ace in the hole. Telekinetic punch and Force Field are further augmented by Force User.

You won’t be bored as fast as playing a SI crossbow build since there are lot of variety in gameplay. You can also mix and match different psi schools if you know what you are doing. However, once again your overall damage output is lower than a SI crossbow build.

DEX 5 for Strafe or 6 for Grenadier or 7 for Three-Pointer
AGI 5 for Strafe
PER 10 for Sharpshooter and/or Deadly Snares
WIL 10 for Locus of Control
INT 7 for Bowyer or 8 for extra psi slot
*note: you won’t have enough STAT point at level 1 for both 10 PER and 10 WIL, you will have to use the extra STAT point gain every fourth level to meet feat requirement.

Level 30: STR 3 DEX 5/6/7 AGI 5 CON 3 PER as high as possible WIL 10 INT 7/8

Specialization recommendation
  • [Get this first] 10 specialization points on Critical Power to maximize your critical damage bonus
  • 5 specialization points on Elemental Bolts for increased damage. Mathematically speaking, you get more damage when you spend 5 specialization points on Bowyer. However, Elemental Bolts is the superior specialization over Bowyer because you have to wait until level 30 to (re)craft your best crossbow(s); whereas if you take Elemental Bolts SP the damage buff applies automatically (level 25 ~ level 30), see details here: https://stygiansoftware.com/forums/index.php?topic=5064.0

You want to spam as many special bolts as your can for your alpha strike, so your primary crossbow should be a Quick Pneumatic Cyclon crossbow (Anatomically-Aware Scope, Pneumatic Reloader).

Special Tactics grants you a free special bolt shot so you should use it with the hardest hitting crossbow w/ total disregard to its base AP cost. Zephyr, with its lower base damage, still out-damage Tornado due to its extra 25% critical damage bonus. Craft a Zephyr with Super String and AA scope as your heavy hitting secondary crossbow.

The unique crossbow Jawbone requires a minimum STR of 6, meaning it’s just a nice-looking collectible gathering dust somewhere and not a practical weapon.

Considering how late when you get the unique crossbow Needler, combine w/ its low critical damage bonus and limited usefulness of Piercing shot means it’s yet another flashy-looking collectible.

Essential equipment, combat utility and psi loadout
  • Bolt Quiver – get and wear one ASAP, this means you’ll have three combat utility slots
  • Quick Pneumatic Cyclon crossbow (Anatomically-Aware Scope, Pneumatic Reloader) for 14 AP special bolt spam
  • Scoped Super Zephyr crossbow (Super String, AA scope)
  • Hardcore chips
  • Focus Stims
  • Night vision Seeker Goggles - turn it on to eliminate darkness range penalty, which will vastly increase your accuracy in general. Get any type of night vision googles asap.
  • Infused Rathound leather armor

Once you have 100% critical hit chance, you’ll immediately notice damage over time (DoT) special bolts (Broadhead/Serrated/various Poison bolts) are objectively inferior to instant damage special bots (Acid/Rusting Acid/Corrosive Acid/Incendiary/Shock bolts). The Elemental Bolts feat tilted the scales of power further in favor of instant damage special bolts. Tranquilizing Bolt is hot garbage due to its 12 turns cooldown(!), deals only one fourth of normal bolt damage and only works on organic targets. Do not waste a combat utility slots w/ Tranquilizing bolt.

Acid bolts – have the lowest instant add-on damage (10 to 25 acid damage without Elemental Bolts) but will probably occupy one of your three combat utility slots majority of the time as they can be easily craft in massive quantity by farming mutants + mutated dogs or purchase from vendors, and acid being one of the less commonly resisted damage type

Rusting Acid bolts – an upgrade to acid bolts, deals 14 to 37 acid damage without Elemental Bolts and additional 35% acid damage against vehicles and machines (meaning they are great against jetskis and robots). You probably won’t have access to this until mid to late game as it’s a Black Sea (expedition DLC area) exclusive item or from selected vendors once you completed certain quests. It’s not easy to stockpile them as you will need to farm Sea Wyrm for their rusting acid gland and/or buy them in limited quantities from vendors. To be honest they don’t really see much use as high tier Shock bolts (which are available much earlier and readily available) are acceptable substitution for them.

Corrosive Acid bolts – top tier acid bolts dealing 20 to 50 acid damage without Elemental Bolts, also proc corroded debuff which reduces all damage resistances and threshold by 7% for 5 turns per stacks with a max possible stack of 10 (thus at max stack = 70% damage resist + threshold reduction). You can gain access to Corrosive Acid mid to late game by joining the pirate in the Black Sea AND unlock the special merchandise tier from a certain pirate vendor. Otherwise you’ll only gain access to this in the final area at late game. They are exceptionally powerful but rare, so save them for bosses and enemies with high mechanical/acid/shock resistances.

Incendiary Bolts – comes in MK I, II and III versions. Without Elemental Bolts, these bolts will burn everything along its path to the target for 9 to 11 (MK I)/13 to 17 (MK II)/17 to 23 (MK III) heat damage which CANNOT CRIT. If the target is hit it takes normal bolt damage plus 18 to 22 (MK I)/26 to 34 (MK II)/34 to 46 (MK III) heat damage and has 50% chance to be set on fire taking the total heat damage suffered again over the course of 2 turns. While on paper these bolts are superior to acid bolts, they are generally inferior in practice due to heat damage being the second most commonly resist damage type (with mechanical damage resist being the most common). The 50% burn chance is too unreliable to proc and becomes irrelevant by mid to late game when you can one/two shot everything with acid/shock special bolts. MK I and II version are readily available but the MK III version are rare; MK III bolts are rarely found as loot/sold by vendors and Napalm C, the component required to craft MK III incendiary bolts, is rarely found as loot/sold in extremely limited quantity by vendors. Personally, I don’t use them often.
Crossbows part IV
Shock Bolts – come in MK I, II and III versions. Without Elemental Bolts, these bolts will strike the targets for normal bolt damage plus 3 to 33 (MK I)/6 to 51 (MK II)/9 to 69 (MK III) electricity damage. Unless the target completely resists the damage, it’s stunned for 1 turn and the electricity jumps to all adjacent targets dealing 1 to 16 (MK I)/3 to 25 (MK II)/4 to 34 (MK III) electric damage. Works on both organic and mechanical targets. Shock bolts are the best special bolts, period, because:
  1. Readily available if you have at least 60 effective Electronics as their crafting components are super common.
  2. Both primary target and adjacent targets electricity damage can critical hit, so it’s a very effective AOE attack with a small radius.
  3. Electricity damage being one of the least commonly resist damage type (energy being the other).
  4. Can stun enemy.
  5. Spam-able with no cooldown.

Shock Bolts should occupy one of your three combat utility slots 99.99% of the time. The only time they are not in your loadout is when facing enemies immune to electricity. You should rush your Electronics to 60 effective ASAP for Shock bolts MK III.

In general, by mid to late game your three combat utility slots should be loaded w/ Acid bolts, Shock bolts and Flashbang. Flashbang is there to provide CC and to proc Opportunist.

You psi loadout should be: Limited Temporal Increment, Psycho-temporal Contraction, Stasis, Electrokinesis and Electrokinetic Imprint.

General tactics
"The last thing you never see."
- NCR 1st Recon’s Motto

The optimal way to play is manually start combat from stealth, activate Special Tactics, and start spamming special bolts: bombard enemy clusters + tough targets using shock bolts and use acid bolts on everything else, killing everything within sight in *relative silent*, rinse and repeat ad nauseum. Take the 1st Recon motto to heart: (be) the last thing you (the enemy) never see. If there’s only one enemy left after your alpha strike, stun it using Premeditated Electrokinesis. If there’s more than one enemy left after your alpha strike, cast Stasis on yourself and try again. You can always disengage any fight by using Vanishing Powder Grenade but I never need to use them when playing SI crossbow (sample build below).
*note: Crossbows in general are noiseless, but will make some noise when firing Shock bolts. Shooting a shock bolt will generates a noise level of 15 center at the shooter, if hit, the bolt will generates a noise level of 3 center at the point of impact. Flashbang is LOUD generating a noise level of 30 center at the point of impact. Walls modify noise by 5 and thick walls by 10. See https://stygiansoftware.com/wiki/index.php?title=Noise and https://stygiansoftware.com/forums/index.php?topic=6136.0 for further details.

Additional comments
See https://steamcommunity.com/sharedfiles/filedetails/?id=2193180857 for Survivor Grosjean’s guide on Yet Another Hybrid Build - Shooting Spree Crossbow Marksman

See https://stygiansoftware.com/forums/index.php?topic=4615.0 for Kiruha’s guide on Crossbow Dominating Build (without Aimed shot and snipe)

  • Remember to stock up on Fusion cell, Micro Electroshock Discharger for shock bolt crafting whenever you shop. You should also stock up on Hardcore chips and Focus Stims.
  • Bolt Quiver could be hard to find, so just try your best to get it ASAP.
  • Always be on the look out for high quality crafting components for crossbows and night vision seeker goggles.
  • You can activate your night vision goggles by first equipping the charged goggles and then drag it onto your hot bar. Note you can not do this (drag it onto your hot bar) while in combat.
  • Toxic gas + plasma grenade, poisoned bear traps and poisoned caltrops are your friends when fighting critical immune enemies.
  • You can lure enemies into a group by making noise (grenade/TNT) or by throwing gas grenade for enemies to disarm while staying hidden (to do this, stand outside the view range of enemies, throw the gas grenade as far as you can towards the enemies and run away/enter stealth). You can also lump enemies together using caltrops. Once enemies are cluster together, start your shock bolt orbital bombardment. :)

Sample build

Start: STR 3 DEX 5 AGI 5 CON 9 PER 9 WIL 3 INT 6

At level 4, put 1 point to DEX for Grenadier.
At level 8, put 1 point to INT for Bowyer.
Pump all remaining STAT points to PER.

You will be relying on bear traps, grenade and caltrop for your early game. You should be able to get around 75% critical chance as early as level 12 (at which point things are now much easier), reaching 100% critical chance at level 26.

If you want some other skill the skill points in Hacking, Lockpicking, Traps and Pickpocketing are all optional. If that’s not enough you can also take some skill points from Stealth and Biology.

Crossbows skill is priority number one, max at every level, no exception!

Second priority would be getting enough base skill to qualify for feats

Priority number three are some key effective skill targets in which you want to rush as early as possible, in decreasing order of importance:
  1. 69 chemistry and 10 mechanics for MK IV grenades
  2. 10 effective tailoring for incendiary grenades.
  3. 60 electronics for Shock bolts MK III
  4. 50 biology for Focus stim
  5. 55 BASE Temporal Manipulation (TM) for PTC and 70 BASE TM for Stasis.

Remaining skill point allocation should be prioritizes as follow, in order of decreasing importance:
  1. Stealth
  2. Throwing
  3. Pickpocketing
  4. Hacking
  5. Lockpicking
  6. Mercantile
  7. Temporal Manipulation
  8. Psychokinesis
  9. Mechanics (will depends on quality of components available to you, if you can craft a better crossbow by leveling up mechanics some more jumping the queue, do it!)
  10. Chemistry
  11. Biology
  12. Tailoring
  13. Electronics
  14. Traps

This build was fully play tested and tweaked to be viable on any difficulty; I completed a version dominating classic game using it on Nov 2020.
Ultimate (Sledge)hammer guide by Hammer Wizard
Hammer Wizard did some extensive research regarding sledgehammer build. I reviewed them all on 22 Nov 2020 and everything checked out. I highly recommend his guide if you are looking for a sledgehammer build.
Psi - Preface
Psi, or Psionic, is Underrail's version of magic. In a similar vein Psionic abilities are Underrail's version of spells.

Changes to psi system
Version, released on July 21, 2020 is a massive overhaul to psi mechanics. It was initially tested on the experimental branch, and became the main branch officially on Sep 7, 2020. To call these changes controversial would be an understatement. There were people for and against the new psi system and you can read them all yourselves:

The new system added the following core concepts:
  • Psi reserves: reserves is five times the number of maximum psi points and can be further increase by 30% by taking the Expanded Psi Capacitance feat.
  • Psi regeneration and restoration:
    • Psi regenerate naturally, every turn in combat or every 5 seconds out of combat.
    • Once reserves are depleted, the character cannot regenerate psi points naturally any more until refilling with a psi inhalant.
    • Psi inhalant fully recover psi points and reserves but cannot be used in combat.
    • Psi booster also draws from psi reserves in order to restore psi points. If reserves lack enough points, those missing points are generated at 50% efficiency.
      For example, you are in combat and reserves are zero, psi booster will restore 38 psi points instead of the normal 75 points.
  • Psi slots and innervation:
    • Characters have a limited number of psi slots and psi abilities must be innervated into them in the Psi Abilities menu, or [P] key, before they can be invoked.
    • Number of naturally available psi slots depends on Intelligence: 2 + INT/2, up to maximum of 8, rounded down.
    • Psionic headbands crafted with a Psi Circuit Extension can increase psi slots past the natural limit.
    • Innervating psi abilities from multiple disciplines increases base psi cost: +10% for each discipline. This penalty can be altered with either Psycho-neural Flexibility or Psycho-neural Optimization feat.
    • Changing innervated abilities removes all current psi points and reserves, and cannot be done in combat.

The old psi system that was used from alpha version up to version (2015 March - 2020 July) is significantly different and is still available in the Legacy branch on Steam and GOG Galaxy, but receives no updates nor bugfixes.

It has no concept of psi reserves nor psi slots. Psi fully regenerates and doesn't require consumables to refill, except when needing a quick boost. Psi characters are free to invoke any of their psi abilities at any time, at normal cost.

Under the old system, psi is a newbie friendly, top tier build: easy to build, learn and use, with a vast array of spells to choose from. Psi build only need high WIL and 6 INT for Premeditation, and is never boring; it allows shenanigans and variety in game play which makes it fun. You can still play it under the legacy branch (version by opening your Steam library, right click on Underrail -> properties... -> click on "BETAS" tab at the top -> select legacy version. You'll do fine if you follow some simple rules: make sure you get all four schools + learn all psi abilities for maximum utility, have at least 6 INT and high WIL, and take the following feats for Tranquility build: Tranquility, Force User, Premeditation, and Locus of Control; For Psychosis build, take: Survival Instincts, Psychosis, Force User, Premeditation, Psionic Mania, Neural Overclocking and Locus of Control. You can pre-cast Cryo-Shield and PSP before starting a hard fight for two additional layers of "free" defense.

Everything written about psi from this point on refer and apply to the new psi system.

With the release of expedition DLC, now any build (even with 3 WIL) could integrate a bit of psi and become much more powerful:

Premeditation need 6 INT and is a must have. Locus of Control is very powerful but it requires 10 WIL, which is way too costly for most psi hybrid build. Therefore, unless you absolutely knows what you are doing, I would recommend a 3 WIL, 6 INT setup for most psi hybrid build.

Base psi skill point allocation:
Must have:
0 Thought Control - 3 WIL is too low to use TC

70 Temporal Manipulation - Limited Temporal Increment (LTI) and Psycho-temporal Contraction (PTC) are excellent support psi abilties. Stasis is a great CC, offensive and defensive three-in-one ability. You can use Stasis to take one enemy out of the fight for 2 turns. You can Stasis an enemy w/ Pseudo-spatial Projection (PSP) and strip it of PSP while it's under stasis. You can net/EMP a stasis enemy (high chance to net regardless of target's evasion). PTC lasts 2 turns and adrenaline shot lasts 3 turns. On the turn when PTC is about to expire you can use every last bit of AP until you have 15 AP left, Stasis yourself, wait 2 turns and extend your max AP by another turn. Important skill/psi ability is on cooldown and can't be use? LTI + Stasis. Stasis is worth it for the extra 15 skill points investment.

Optional, take only one additional psi school unless you know what you are doing:
45 Psychokinesis - Force Field, Electrokinesis, Disruptive Field, Electrokinetic Imprint are all important CC abilities, try to take the Force User feat if you choose this school.

70 base or 140 effective Metathermics - Cryokinesis extreme range sniping + incendiary grenade area denial is a lifesaver early game (you'll eventually outgrown this tactic as you level up). Cryostasis is a very good CC ability because it's silent and works on enemy under second wind (stun immune). Thermodynamic Destabilization damage is a true AoE ability that's based on enemy HP (capped at 100% enemy HP which is reachable w/ 140 effective Metathermics). Cryo-shield is great against weak, multiple hits per turn melee type such as Burrower spawn, Rathound, Dog, etc, and can remove Burning status effect on the player. Exothermic Aura is extremely useful against Giant Weaver found in expedition as you are immune to webbed while Exothermic Aura is active (4 turns).

In conclusion - you only need to invest 3 points in INT, 1 feat slot, 115+ skill points and sacrifice 20% base HP to gain a few exceptionally helpful psi abilities. The cost–benefit analysis overwhelmingly favors psi hybrid build over non-psi build; There's really no reason to handicap yourself playing non-psi build unless you really want to.
Psi - Psionic abilities part I
My highly biased commentary on all psionic abilites:

Thought Control
Silent, Neural Overload is deadly mid~late game and bypass resistance, comes w/ lots of CC options.

  • Does not work on non-organic, at all.
  • No area of effect (AoE) ability except when combine with Locus of Control (LoC), which has a long cool down of 15 turns.
  • Most abilities within this school can be resisted or mitigated by enemy resolve and/or fortitude.

Neural Overload (NO) - bread and butter of a TC char, spam-able, cheap psi cost, weak at early game, can one/two shot everything starting from mid game if you spec for it, worth a slot.

Frighten - not a bad ability, it's just that there are other better options and slot space is at a premium.

Bilocation - usually use w/ LoC (AoE radius changed to 2, down from 3) and/or Mental Breakdown + Force Field, still powerful, worth a slot.

Mental Breakdown - has effect on other detrimental thought control abilities:
  • Neural Overload: Double damage
  • Frighten: Double duration
  • Enrage: Double duration
  • Neurovisual Disruption: Double duration
  • Psi-cognitive Interruption: Double psi burn and duration
  • Bilocation: Two doppelgangers
A two-in-one CC and damage boosting (by reducing enemy resolve) ability, worth a slot.

Psi-cognitive Interruption - situationally useful, like when fighting against hordes of Azuridae and Azuridae Goliathus, usually not worth a slot.

Enrage - similar to Biolocation, usually use w/ LoC and/or Force Field, recent nerf of LoC and Enrage (maximum duration changed to 2, down from 4) reduced its effectiveness but still powerful, worth a slot.

Pseudo-spatial Projection (PSP) - only useful for certain build/under certain situations as enemy using burst (smg, AR, shotgun) can easily strip you of its protection, may or may not be worth a slot.

Neurovisual Disruption - too weak to ever justify using a slot for it.

  • Works on everything.
  • Arguably the strongest psi school against a single target.
  • Telekinetic Proxy + Implosion/Telekinetic Punch are deadly.
  • Force field.
  • One of the two psi school that can effectively damage high tier robots such as Industrial bots and Naga Protectors
Con: no AoE and no spammable ability except Electrokinesis, which has its own problems

Telekinetic Punch (TP) - the stun is unreliable unless you have high Psychokinesis. One of Psychokinesis main bread and butter ability when used w/ Telekinetic Proxy, damage can be further increased by taking the Force User feat, worth a slot.

Force Field (FF) - unreliable and will get you kill if you have low Psychokinesis, therefore not recommended for use when playing a 3 WIL psi hybrid, don't waste your slot. If you have high Psychokinesis and/or took Force User, this is a very powerful CC abilities, worth a slot.

Electrokinesis - 3 WIL hybrid will use this for its reliable, on demand stun, usually used w/ Premediation. This can be your main damage psi ability if you have high Psychokinesis. The problem, is that it costs a lot of action points, and there are situations where using Electrokinesis is problematic:
  • TP + Implosion are on cooldown. 1 enemy remain, use of Electrokinesis is just ... wasteful. The best choice here is the spam-able Cryokinesis or NO.
  • You can more or less "focus fire" Cryokinetic Orb because you know it will spread out evenly as a circle and closer to landing point = usually more damage. You can't do that with Electrokinesis.
  • When using Cryo Orb against a crowd you often don't know who will or will not get hit but the damage is usually still more or less evenly spread-out among them, or just use Pyrokinesis/Thermodynamic Destabilization for true AoE (everyone take the same damage before evasion damage reduction); Thus you should use Cryo Orb first and followup with a grenade to finish everyone off, more targets = more chance for Cryo Orb to do its magic. If you use a grenade first and than cryo orb it might results in enemies standing.
    Facing the exact situation Electrokinesis will jump randomly - if you use Electrokinesis first the damage might get very unevenly spread so grenade won't finish off the crowd. If you use grenade first it could result in enemies having a gap that is too wide for Electrokinesis to jump. Electrokinesis could also jump to a "dead zone" where it killed a target, jump to the next and now the gap is too wide for it to jump back and continue.
Having said that, Electrokinesis is a very good psi ability but its use requires a certain amount of luck and finesse to it, worth a slot.

Force Emission - some people swear by it when playing psi monk. I think it's garbage:
  • While the raw damage on paper could be significant, its damage is a new separate mechanical attack that's roll individually against enemies' mechanical resist/threshold which will usually vastly decrease its effective damage.
  • You can get as low as 4 action point per attack if you have high DEX. If you use Force Emission every hit it'll rapidly drains your psi points, leaving you unable to cast other psi abilities when you need them.
Garbage, even for psi monk, don't waste your slot. If you want to try planning a build around it w/ Force User and Telekinetic Proxy, create a new manual save file before the attempt, just in case you want to roll back your char.
note: It had been brought to my attention Force Emission would be good for a bare fist char, see comment from sheepherder: https://stygiansoftware.com/forums/index.php?topic=6168.msg32398#msg32398

Disruptive Field - when examine in isolation it's pretty good, can increase a sniper/crossbow npc's chance to miss by 85%. However, can you really afford to use a slot on it when there are other objectively better options available?

Electrokinetic Imprint - a psi version of the almighty bear trap, reliable stun, this is a powerful CC abilities, worth a slot.

Telekinetic Proxy - bread and butter for a Psychokinesis build, can be useful for a 3 WIL hybrid as its light can proc Ambush & *silent*, worth a slot.

Implosion - bread and butter for a Psychokinesis build, use w/ Telekinetic Proxy, worth a slot.

Pro: Fire proc fear, long range and AoE psi abilities.
Cons: Very ineffective against robots, LOUD (see noise: https://stygiansoftware.com/wiki/index.php?title=Noise )

Cryokinesis - you can snipe w/ it due to its long range, cost a lot of action points to cast but cheap on psi points, spam-able, worth a slot.

Pyrokinesis - AoE, can proc mass fear if you take Pyromaniac, can land unpredictably like a grenade so it's possible to suicide w/ it, still, worth a slot.

Cryostasis - its main selling point is that it's silent, cheap on action point but costs a lot of psi points to cast. You can take Cryogenic Induction + Exposed Weakness for guarantee meme tier shattering but this setup is not really that practical due to Cryostasis' eight turn cool down + melee requirements, worth a slot.

Pyrokinetic Stream - another fire ability that works w/ Pyromaniac but you need to be careful w/ it because it can completely drains your psi points as an unwanted side effect, may or may not be worth a slot.
Psi - Psionic abilities part II
Cryokinetic Orb (Cryo orb) - THE, MAIN, NUMBER ONE, damage dealing ability for a SI Psychosis psi, very powerful but can be unpredictable. You need to practice with it a bit before you can use it to its full potential (just imagine a circle at the landing tile, 24 shards fan out evenly to cover a full 360 degree circle and you'll know which tile to target), well worth a slot.

Thermodynamic Destabilization (ThermoD) - recent nerf capped it at 100% enemy HP, which can be reach at 140 effective Metathermics; It also got a slight buff by way of reduced action point cost, still powerful and a strong candidate for a slot. Pyromaniac will not work w/ it; this is a known bug and only god knows when Styg will fix it.

Cryo-Shield - see preface comment on it; Whether it's worth a slot or not will depends on the situation.

Exothermic Aura - see preface comment on it; Whether it's worth a slot or not will depends on the situation.

Temporal Manipulation
Pro: Great support Psi school, all optimized build should have at least 55 (usually 70) skill points invested in it. A TM-only psi is viable, powerful even, but not exactly newbie friendly.
Con: cannot critical hit, no exception.

Temporal Distortion - use this against turrets, high tier robots like Industrial bots and Naga Protectors. Decent psi ability at early game even with minimal skill point investment. Worth a slot in early game, or when fighting against turrets, robots or when playing specialized build. Sometimes it's easy to forget Stasis was originally designed to boost its damage. :)

Limited Temporal Increment (LTI) - exceptional support psi ability that will usually occupy one of your slots. This ability and the feat Grenadier is a match made in heaven.

Psycho-temporal Dilation - opportunity cost of taking this is probably too high to justify using one of your precious slots on it.

Entropic Recurrence -
Originally posted by Tamiore:
Was meme-tier before, still is. ¯\_(ツ)_/¯
Agree, don't waste your slot.

Psycho-temporal Contraction (PTC) - see preface comment on it, should and will occupy one of your slots at all times.
note: Once its effect expires there is a chance for the target to be afflicted by the Psycho-temporal Dilation debuff with random duration and intensity, chance of this happening starts at 60% and will drop down to a minimum of 30% at around 150 effective TM (see https://stygiansoftware.com/forums/index.php?topic=6111.msg32204#msg32204 and https://i.imgur.com/5cz9aRc.jpg ). You can easily reach 150+ effective TM if you invest 70 base TM and max out at least one other psi school.

Temporary Rewind -
Originally posted by Tamiore:
Was hot garbage before, still is.
Agree, don't waste your slot.

Precognition - only useful for specific build, generally not worth taking up a slot.

Stasis - see preface comment on it, should and will occupy one of your slots at all times.
Psi - Psychosis build part I
As a psi char you have two options: Tranquility route, keeping your HP full at all times reducing the action point cost of casting so you can cast as many psi abilities per turn as possible, or; Psychosis route focusing on getting critical chance and critical damage bonus as high as possible. Generally speaking, you are playing a Psychosis psi char wrong if you can’t end a fight within the first couple turns.

Overall class ranking
(Top > Middle > Bottom; Newbie friendly > Manual required > Newbie unfriendly)
Top; Newbie unfriendly
Psi build are outright hostile to newbie now, in addition to learning the game itself, you need to understand psi build specific such as:
  1. Psi points and Psi reserves management
  2. Proper gear setup
  3. Psi slots and innervation
    • Innervating psi abilities from multiple disciplines increases base psi cost: +10% for each discipline. Psychosis increases base psi cost another +20%. This means you need at least a rough idea which psi school(s) you are going for right from the start. Unfortunately, the information is not well-presented anywhere to allow a newbie to make informed decisions, not even on the wiki. When done badly it’s possible to enter battle w/ a multi school loadout realizing it doesn’t work due to absurdly high psi point cost to cast.
    • Slots are limited and innervation is not possible during combat, so switching things on the fly is out. Which psi abilities would make a good loadout? Under what situation? Again, the information is not well-presented anywhere to allow a newbie to make informed decisions.
As you can see the new psi system is pretty hostile to a new player playing blind. Don’t use a pure psi build as your first char.

  • High damage output killing everything within a couple turns, you are death incarnate.

  • Due to the increase psi point cost a psychosis build does not have staying power. If a fight drags on for too long you will run out of psi points.
  • Weak against critical immune enemies (thankfully, they are relatively rare in the game: Bladlings, Shrooming Chompers/Spitter and Spore Turret) due to heavy reliant on critical hit.
  • Glass cannon
  • Could be boring as the current meta means the optimal way to play is to spam a few psi abilities over and over

The basics
You already taken 1 psi school TM for LTI, PTC and Stasis. Due to the innervation mechanic, you are strongly advised to pick a maximum of two (2) additional psi school, which two is up to you. You will usually fight w/ a two school loadout. Tri-school loadout would work around mid ~ late game. Keep in mind only the following psi abilities can critical hit:
Thought Control: Neural Overload, Psi-Cognitive Interruption
Psychokinesis: Telekinetic Punch, Electrokinesis
Metathermics: Cryokinesis, Pyrokinesis, Cryokinetic Orb
Temporal Manipulation: NONE

You want to get your psi critical chance as high as possible, sources of critical chance:
5% = base
Psychosis + 15%, +10% w/ 10 specialization
30% from Survival Instinct, + 5% w/ 5 specialization
Focus Stim = +15%
School specific psi headband, top quality Proximal Neuroscopic Filter at late game = +19%
Total = (5 + 15 + 10 + 30 + 5 + 15 + 19) % = 99% critical chance at mid ~ late game

You want to get your psi critical damage bonus as high as possible, sources of critical damage bonus:
Base = +100%
Neural Overclocking = +30%
School specific psi head, top quality Stable Neural Amplifier at late game = +95%
Sørmirbæren Spirit Staff = +40%
Pickled Mindshrooms = +40%
Trance = +100% (but increases psi cost by 20%)
Total = (100 + 30 + 95 + 40) % = +265% without aid of food and drugs or
Total = (265 + 40 + 100) % = +405%

If your main school is TC, your tactic would generally be:
LoC + Mental Breakdown groups -> NO spam

If your main school is Psychokinesis, your tactic would generally be:
Electrokinesis spam. Telekinetic Proxy + Implosion (5 turn cooldown) /Telekinetic Punch (3 turn cooldown) are your ace in the hole. Force Field for CC.

If your main school is Metathermics, your tactic would generally be:
Cryo-orb open -> (if still large group remain, Pyrokinesis) -> Cryokinesis spam -> Cryostasis for CC. ThermoD + grenade/Pyrokinesis/Pyrokinetic Stream is another AoE attack against groups.

Core skills
  • Mechanics: 65 effective is the minimum in order to craft Motion Tracking Goggles; 128 effective for top tier Tactical Vest/use infused leather; 162 being the maximum to use expedition infused leather boots to craft melee immunity armor set.
  • Electronics: 137 effective is the maximum for top tier psi headband and is the recommended minimum for the build; 167 effective to craft night vision Motion Tracking Goggles; max is 194 effective for perfect quality energy shield but its components are only available in/after the final area. Recommended effective electronics is somewhere between 167 to 194 effective.
  • Biology: 50 effective is the absolute minimum for Focus Stims; 70 effective will get you Trance, and Hypercerebrix which is vital for crafting; 100 effective will get you Super Health Hypo. Because you want to manage your health % (under 30% for SI, under 25% for Fight Response) you probably want to stop here as you won’t get much value out of Regenerative Mixture and Super Soldier Drugs.
  • Tailoring: 156 effective will allow you to craft the best Tactical Vest; Max value is at 179 effective for various infused leather armors. I would recommend an effective tailoring value somewhere below 179, depending on the quality of components found in your run.
  • Temporal Manipulation: 55 BASE skill is the absolute minimum to get PTC, 70 BASE skill will get you Stasis which is a valuable offensive and defensive psi ability. I highly recommend you aim for 70 BASE skill, and max out two other psi schools of your choosing.

Non-core skills but recommended
  • **highly recommended** 105 effective mercantile to unlock all special merchandise tiers in order to increase your chance of obtaining high quality crafting components
  • 80 effective throwing for 90% THC grenade throw to 4 tiles away from you
  • 69 effective chemistry for MK IV grenades
  • 30 BASE Psychokinesis for Electrokinesis should you decided not to max Psychokinesis school

Core feats
  • Survival Instinct
    requirement: level 1, CON 9
    reason for inclusion: 30% critical chance when under 30% health, required to obtain 99% critical chance.
  • Psychosis
    requirement: level 1, Psi Empathy
    reason for inclusion: +15% critical chance, required to obtain 99% critical chance.
  • Premeditation
    requirement: level 6, INT 6, any psi skill 40
    reason for inclusion: a must have feat for all build using psi.
  • Psionic Mania
    requirement: level 8, WIL 8, any psi skill 50, Psychosis
    reason for inclusion: early in the game you won’t have 99% critical chance. This feat grant you an ability making your next offensive psi ability an automatic critical hit at the cost of 15% of your HP.
  • Psycho-Neural Flexibility
    requirement: Level 9, INT 8, any psi skill 55, Psi empathy
    reason for inclusion: the increase psi cost from Psychosis is no joke, you need this to counter the multi school psi cost penalty.
  • Locus of Control
    requirement: level 13, WIL 10, Thought Control 75, Psi empathy
    reason for inclusion: gain immunity to stun, fear, incapacitation, and mind control. LoC + TC ability = AoE TC, must have for psi char if you could afford the 10 WIL requirement.
  • Neural Overclocking
    requirement: level 11, WIL 10, any psi skill 65, Psi empathy
    reason for inclusion: boost psi critical damage bonus.
Psi - Psychosis build part II
Non-core feats but recommended
  • Stoicism
    requirement: level 1, CON 7, WIL 7
    reason for inclusion: because we need SI we’ll be running around at below 30% health all the time. This feat is a perfect fit and can be a lifesaver by reducing all incoming damage.
  • Grenadier
    requirement: level 4, DEX 6, Throwing 30
    reason for inclusion: Due to the increased psi cost running as a Psychosis psi we need additional source of damage and CC that doesn’t cost psi. Grenade fits the bill perfectly, get this, combined w/ LTI we can use 1 damage grenade on turn 1 and immediately use another damage grenade on turn 2.
  • Cerebral Trauma
    requirement: level 3, Thought Control 25, Psi Empathy
    reason for inclusion: take this if you decided to focus on Thought Control, otherwise just skip it.
  • Force User
    requirement: level 3, WIL 7, Psychokinesis 25, Psi Empathy
    reason for inclusion: take this if you decided to focus on Psychokinesis, otherwise just skip it.
  • Fight Response
    requirement: level 26, WIL 7
    reason for inclusion: +10 action point per turn when starting a turn below 25% health, another feat that’s a perfect fit for a SI Psychosis psi.
  • Advanced Psi Empathy
    requirement: level 26, any psi skill 100, Psi Empathy
    reason for inclusion: the reduced psi cost is very nice should you want to run a tri-school loadout at mid ~ late game.
  • Increased WIL
    requirement: level 26
    reason for inclusion: you could take increased INT for another slot but that’s usually not needed. The sweet spot for INT is generally considered to be 8 to qualify for Psycho-Neural Flexibility granting you six slots. I think the increased damage is more important than one extra slot, your choice really.

STAT allocation
Based on core feats the absolute minimum STAT for a SI Psychosis build is:
STR 3 DEX 3 AGI 3 CON 9 PER 3 WIL 10 INT 8

Known viable build variants
High mobility Blitz Psychosis psi – basically pump all extra STAT point to AGI in order to get Blitz at level 24. High AGI = very effective dodge & evasion = very resilient for a glass cannon (still running around below 30% HP at all times, dodge & evasion are your first line of defense; armor and shield are your second line of defense; damage reduction from Stoicism + Aegis + Morphine are your last line of defense) and high MP means you can outrun everything. This build will still use grenades but no Grenadier due to low DEX.

AGI 6 for Sprint
CON 9 Survival Instinct
INT 8 for Psycho-Neural Flexibility

Level 4 +1 AGI, level 8 +1 WIL, level 12 +1 WIL (so you can get LoC at level 14), level 16 +1 AGI, level 20 +1 AGI, level 24 +1 AGI

Level 30: STR 3 DEX 3 AGI 10 CON 9 PER 3 WIL as high as possible INT 8
Psi damage will scale w/ your effective psi skill so pump WIL as high as you can for maximum damage.

Specialization recommendations
  • [Get this first] 10 specialization points on Psychosis: Critical Chance
  • 5 specialization points on Survival Instincts: Critical Chance

General tactics
The ideal way to play a Psychosis psi is start a turn manually, killing everything on turn 1 and exit combat. This is entirely possible for majority of the game if you take things slow and use all available tactics such as divide and conquer, lure everyone on the map to a single point/pre-prep kill zone w/ traps/caltrops/toxic gas grenade using noise, thin out the crowd by silent assassination of stray target/small group, etc. On some maps it's possible to kite kill everything by using long range psi abilities such as Cryokinesis. You can also completely block enemy pathway to you with level 2+ fire (magnesium/napalm grenades) and kill everything using long range psi abilities. The key is to avoid fighting a drawn-out battle. If all else fails, you can use Vanishing Powder Grenade to disengage if you have access to it.

Additional comments
  • As a crit psi build you should finish majority of fights before PTC buff ran out so you shouldn't care about PTC debuff chance. In addition, if you have 70 base TM and max out at least one other psi school, you should be able to reach PTC minimal debuff chance without any additional skill point investments in TM.
  • Expanded Psi Capacitance is a bad feat for Psychosis psi because you should finish majority of fight within the first few turns. If you are running out of psi reserves all the time, chances are you are doing something wrong.
  • Pure psi with no crafting is just objectively bad. School specific psi headbands are vital and will make a night and day difference in damage output. If you don't craft as a psi, the whole game sucks and DC sucks even more.
  • Grenade is a good source of damage and CC that does not requires any psi points, use them.
  • High tier robots such as Industrial bots and Naga Protector are best killed using EMP mines and grenades. You can also use Temporal Distortion (best way) and/or Electrokinesis (second best way) in addition to EMP, and wear school/psi ability specific psi headband to buff your psi damage. Another option would be to just stealth pass and avoid fighting them altogether.
  • Visit food vendors often and buy up all available Pickled Mindshroom and Psi Beetle Brain Soup.
  • I've played a dual/Tri psi school Psychosis build and the additional psi cost is only tough early game (stock up on Psi Beetle Brain Soup) but manageable. It worked fine once you have the proper gear (rush craft a psi beetle tact vest asap) and feats (Psycho-neural Flexibility - One psi school is ignored when determining the multi-school innervation psi cost penalty, available at level 10 and Advanced Psi Empathy).

Sample build

Start: STR 3 DEX 5 AGI 3 CON 9 PER 3 WIL 9 INT 8

At level 4, put 1 point to DEX for Grenadier.
At level 8, put 1 point to WIL.
At level 12, put 1 point to DEX.
At level 16, put 1 point to DEX, after this, all extra STAT points to WIL.

Early game you will be leveling only Metathermics and Temporal Manipulation, and fight by kiting using Cryokinesis/stop enemies from reaching you using incendiary grenades. Bear traps, grenade and caltrop are also extremely useful. Once you have Psionic Mania you have a guarantee psi critical hit every alpha strike and that's when things starts to get easier. You'll start maxing out Thought Control starting at around level 16, granting you the option to silently assassinate enemies using NO. Fatal Throw, Quick Tinkering and Psycho-Temporal acceleration are optional and could be swap to any other feats of your choosing.

If you want some other skill the skill points in Traps and Persuasion are optional. If that’s not enough you can also take some skill points from Throwing (can lower it to 80 effective if you decided not to take Three-Pointer), Stealth, Mechanics, Electronics, Chemistry (can lower it to 69 effective for MK IV grenades) and Tailoring.

Metathermics skill is priority number one, max at every level, no exception!

Second priority would be getting enough base skill to qualify for feats

Priority number three are some key skill targets in which you want to rush as early as possible, in decreasing order of importance:
  1. Enough mechanics, tailoring, and biology to craft psi beetle tac vest.
  2. 69 effective chemistry and 10 effective mechanics for MK IV grenades
  3. 10 effective tailoring for incendiary grenades.
  4. 25 base TM for LTI.
  5. 30 Psychokinesis for Electrokinesis.
  6. Once you have access to PTC psi mentor, 55 base TM for PTC.
  7. 50 effective biology for Focus Stim.
  8. Once you have access to Stasis psi mentor, 70 base TM for Stasis.
Psi - Psychosis build part III
Remaining skill point allocation should be prioritizes as follow, in order of decreasing importance:
  1. Thought Control (early on just leave it at zero, but make sure you have 75 base Thought Control by level 14 in order to get Locus of Control, you can start maxing it every level starting as early as level 14)
  2. Persuasion
  3. Mercantile
  4. Throwing
  5. Biology (if you need it to craft a better psi headband by jumping the queue, do it!)
  6. Electronics (if you need it to craft a better psi headband by jumping the queue, do it!)
  7. Chemistry
  8. Stealth
  9. Tailoring (I had high Tailoring to craft various expedition infused leather armor set - you can have a lower Tailoring value of your choosing.)
  10. Mechanics (I had high mechanics to craft expedition infused leather armor set for melee immunity - if you don't want it you can invest less skill point on it.)
  11. Traps

My psi abilities loadouts are as follow:
  • Meta + TM frontal assault mode
    Stasis, Psycho-temporal Contraction, Limited Temporal Increment, Cryokinesis, Cryokinetic Orb
    Pyrokinesis OR Thermodynamic Destabilization, usually pyrokinesis as thermoD can only be triggered using grenades.
  • TC + TM silent assassination mode
    Stasis, Psycho-temporal Contraction, Limited Temporal Increment, Neural Overload, Mental Breakdown, *any TC abilities, usually Pseudo-spatial Projection
  • Towards the end game once I have everything setup I just used the following loadout and didn't bother to change it:
    Stasis, Psycho-temporal Contraction, Limited Temporal Increment, Cryokinesis, Cryokinetic Orb, Neural Overload

Comments on sample build:
  • This is a build focusing on Thought Control and Metathermics that I used to beat a version dominating difficulty game on classic mode. Damage is further augmented w/ grenade (Grenadier, Three-Pointer) as well as a late investment into traps + Quick Tinkering to deal w/ high tier robots. I picked Fatal Throw because Three-Pointer already costed 7 DEX and high throwing, might as well go 1 DEX higher to get "free" throwing knife kill.
  • Get Sturdy psionic overcoat (tac vest made using sturdy vest, psi beetle carapace, black cloth) asap. The key part is the psi beetle carapace which grants -10% psi cost. You can and should rush-craft any tac vest using psi beetle carapace as early as possible.
  • Weapons: try to get Sørmirbæren Spirit Staff asap. Sørmirbæren Spirit Staff > Høddurform for this build even when using Neural Overload. Damage over time is moot with your 1hitko Neural Overload.
  • For boots wear ninja tabi majority of the time for stealth and MP bonus. Switch to other resistance specific tabi when situation calls for it: infused mutant dog tabi for acid resistance, infused heart breaker serpent tabi for bio resist and so on ...
  • Psi headband: This is the most important crafting aspect of the build.
    • For legacy branch you want Universal Psionic Modulator, Proximal Neuroscopic Filter and Stable Neural Amplifier
    • If you are not playing legacy branch, you want school specific psi headband instead of Uni-Psi Headband - initially you will only be using two psi schools: Meta + TM, so you should be wearing Neuroscopic Metathermics Amplifier (Metathermic Modulator, Proximal Neuroscopic Filter, Stable Neural Amplifier).

      You should have a few other psi headbands in your inventory so you can switch depending on the situation:
      For TM + TC loadout: Scanning Thought Control Amplifier (Thought Control Modulator, Magnifying Neuroscopic Filter: Neural Overload, Stable Neural Amplifier)

      Against robots: Distortive Muffled Temporal Manupulation Headbands (Temporal Manipulation Modulator, Magnifying Neuroscopic Filter: Temporal Distortion, Psionic Mufflers) or Electrokinetic Psychokinesis Amplifier (Psychokinetic Modulator, Magnifying Neuroscopic Filter: Electrokinesis, Stable Neural Amplifier)

      For Locus Hive Cryo-orb bombing - Cryokinetic Muffled Metathermics Headbands (Metathermic Modulator, Magnifying Neuroscopic Filter: Cryokinetic Orb, Psionic Mufflers).
  • You need 75 base thought control to get Locus of control at level 14 but you won't be using TC at all until you have a Scanning Thought Control amplifier psi headband. You should just leave Thought Control at 75 base until mid game around level 14 ~ 20 ish or so and starting maxing Thought Control every level. Because Neural Overload is silent you can switch to a TC load out to quietly assassinate/thin out crowd. Make sure to activate a cloaking device, wear Scanning Thought Control amplifier psi headband, ninja tabi + infused cave hopper leather armor with black cloth as stealth is on the low side.
Psi mentor location
Psionic mentors for sale:
Psi mentors for all psionic abilities in the game (except one) were added to the random loot table on Version

  • Pasquale from SGS has Stasis (late in the game).
  • Ezra from SGS has Neurovisual Disruption (late in the game, available once you completed Core City faction questline).
  • Fred from Camp Hathor has Entropic Recurrence.
  • Doc from Rail Crossing has Enrage and Psycho-temporal Contraction.
  • Estelle from Foundry has Thermodynamic Destabilization and Precognition.
  • Heidi from Core City has Telekinetic Proxy and Temporary Rewind.
  • Phyllis from Oculus has Pseudo-spatial Projection.
  • Constantine from Oculus has zero to two random mentor available per merchandise restock once you unlock his special merchandise.
    • Psionic Mentors seen on sale from Constantine:
      Disruptive Field
      Electrokinetic Imprint
      Entropic Recurrence
      Exothermic Aura
      Force Field
      Neurovisual Disruption
      Pseudo-spatial Projection
      Psycho-temporal Contraction
      Stasis (rare, but can appear before it's available from Pasquale and Jerre Franz)
      Telekinetic Proxy
      Temporary Rewind
      Thermodynamic Destabilization
  • Jerre Franz from Institute of Tchort has Stasis.
  • Investigator Kiro from Institute of Tchort has Psi-cognitive Interruption.
  • Anastasia from Fort Apogee has Telekinetic Proxy.

Static loot:
  • Foundry bunker, desk (Exothermic Aura)
  • Black Crawler camp, shelves (Cryokinetic Orb)
  • Lurker Base, barrel (Electrokinetic Imprint)

See Psionic mentors[stygiansoftware.com] on the official wiki for a more complete list.

Or you can check out this Steam thread.

Psi abilities requirements at a glance (click on image to enlarge):
List of build by sheepherder
sheepherder posted a lot of dominating viable builds with distinct characteristics on the official forum.

Note they are not min-maxed for optimal damage output (due to self imposed restrictions of minimal use of grenades, traps, caltrop, and not using any weapons that doesn't fit the build's theme), but min-maxed for a theme of his choosing. Anyway, They are all interesting and well worth reading:

The Fastest Hammer in the South - Hammer ninja glass cannon

Underrail is a clicker game – 5mm Hawker pistol glass cannon on Dominating

Casino Underrail - a .44 Hammerer build

Timeless - Temporal Manipulation psi build, with Dodge/Evasion on Dominating

Titan - MAX CON, throwing build on Dominating

Rapid Fire Brain Damage - Though Control specialist on Dominating

Dragon - Metathermics only psi build on Dominating
Expedition DLC part I
Expedition map by Damianus_NT on RPG Codex
Please note the above link and the map itself contains spoilers.

There are various precision penalties while riding a jet ski. Generally for range char you want a jet ski with high stability; for melee char you want a jet ski with high maneuverability.
For psi accuracy is not an issue so it's either max cover or max speed (to run outside enemies' attack range).

Torpedo is ridiculously good for melee/psi char but not so much for a range char due to the low stability resulting in low range accuracy. Shark is a good compromise for a range char - 1 large engine = lot of MP + good stability. The other obvious option is Devastator + good tanky armor but this setup is expensive as ♥♥♥♥.

Reef Jetski is an antique that Ray will pay a lot of charons for. It's worth hauling it back to Core City if you are looking for $ to upgrade your Jetski. The other way is to ride a junk jet from CC to Reef, swap the parts and ride the reef back to CC.

Can you fix any of the broken jetski parts?

Where can I get high end jetski parts?
Some of them are available on sale from Ray once you unlock his special merchandise tier. They are also available as static loot in one of the new dangerous high level waterway dungeon roughly northwest of The Rig.

Ferryman route
Mutie Refuge Dock - B6 ->
Port Ceto Dock - G1 ->
Northeastern Waters Area - I8 ->
Sormirbaren Geyser Village - J11 -> repeat

Hypercerebrix blueprint
There are two static locations for the blueprint:
Level 4 of the Nexus (Biology and Medicine), room opposite of elevator, behind a lockpicking 80 door, middle desk

Under the lighthouse in Port Crag (lone pirate port on the eastern side of the map where Razor is located once you joined the pirates), climb down the ladder and eventually you'll see a room w/ lots of Plasma Turrets (The Great Archive). Once you try to open the gate you'll have to fight four (4) Naga Protectors at the same time on dominating difficulty. Defeat them, release the lock down w/ the computer and enter. The blueprint should be inside one of the cabinets.

rarely sold by Phyllis - chance of this happening is extremely low. It's nice to get it early but don't count on it.

rarely sold by Dr. Savage - again chance of this happening is extremely low.

Talk to Ferryman to gain Philosophy feat. You should always choose the [Intelligent] option when talking to him whenever available. Your char's effective INT will determine the level of the feat:
INT 6 and below = nothing
INT 7 = Philosophy I
INT 8 = Philosophy II
INT 9 = Philosophy III
You can upgrade to a higher level feat when you have a higher effective INT. For example: You have Philosophy I; you will lose Philosophy I and gain Philosophy III when you talk to the Ferryman with 9 effective INT.

Outer Visions
Need minimum 6 effective WIL

Body Horror
No WIL requirement. If you want this feat do not choose any of the WIL checks (accept the visions and memories) and enter the final chamber to do the deed. If you messed up the WIL checks and thus wasn't prepared you would still be able to do the deed if you previously defeated the final boss.

General tactics
Against Locust and Locust Hives
Sometimes you can stealth pass Locust Hives and leave them alone. When that's not possible, the best way to take them out would be:
  • Hives are hyper sensitive to noise. Don't use grenades/TNT/ThermoD unless you are ready to alert all hives on the map. Try not to make too much noise, unfortunately this might not be possible for some builds.
  • Once alerted a Hive will spawn 3 ~ 5 Locust every second turn. Locust numbers are finite for every Hive so you can either take out the Hive within 1 turn and deal w/ 3 ~ 5 Locusts on the next turn OR focus on killing all the Locusts until a Hive run out of Locust. A Locust cannot perform any action on the same turn when it spawn so it's possible for some build to kill them all before they get to attack. The key here is quiet, low AP attack such as leather fist/Knives/silence SMG single shots.
  • If you need to fight them head on I strongly recommend Infused Heartbreaker leather armor and Infused Heartbreaker tabi/boots (maybe a bio headgear as well) for 100% bio immunity + decent mechanical threshold/resist.
  • TNT can take out a Hive in one shot but this should only be use as a last resort.
  • Hives are immune to critical hit, stun, frozen, entanglement and expose weakness.
Expedition DLC part II
Defending Aegis against Natives
You should light the beach area with fire as much as possible. This will fear the Natives and allow Aegis troopers to trigger ambush. Exothermic aura, incendiary grenades and bio gas grenades are very effective here, just be aware of throwing nets from Natives. You could carpet the entire battlefield w/ bear traps, caltrops and mines for a much easier fight.

After the first fight, you can reduce the amount of Natives attacking by patrolling and killing incoming Natives in the surrounding waters maps around the island before starting the defensive fight on the beach.

Against Naga Protectors
Naga stats on dominating difficulty (need more info/testing)
1500 HP
Mechanical: 80% / ?
Heat: 95% / ?
Cold: 100(?)% / ?
Electricity: 50% / 50
Acid: ?% / ?
Energy: 0% / 100
Bio: 100%
Don't use plasma weapon/grenade/trap against them. They are also immune to entanglement. They have a relatively high electricity threshold but high grade EMP grenades/mines are still effective. They have high range but low movement points, so try to use line of sight to make them walk towards you.


In order to talk to Yngwar, you need any one of the following:
100 effective Intimidation
Wield a spear -> assume a fighting stand via dialogue option -> choose: [melee] engage in a spear duel (effective melee threshold unknown, tested 169 = passed; tested 0 = failed)
to start talking to him. He's easily offended so make sure you save before talking to him. When Yngwar refused to answer something don't press it and talk about something else. You will need 9 INT to understand him perfectly and get him to sketch the rune on a piece of leather. If you have lower than 9 INT he will still provide you some lore and info but no rune.

Can you make peace with the Natives?

How do I join the pirates?
Go talk to Razor @ F4. Please note it's not possible to join the pirates after a certain event.

How can you steal an Aegis Patroller without lockpicking?
Go search for Aegis patrol around the Black Sea, kill them all and take their jet. If three of them are too much to handle, you need to wait until they start leaving the map and manually start battle when only one of them is left.
Or you can ask Chief Briggs for a way back to Core City. Once your transport arrive at Core City you can kill him for the jet.
Or you can steal a patroller key from Chief Briggs/random Aegis trooper.

Spoiler alert

Spoiler alert

The shard and Eternal Torch
You can obtain the Eternal Torch by finding the shard in the graveyard.
1) You must first discover the exact body parts from either from the Ferryman or Yngwar.
2) You will also need to discover the symbol for the correct hoist to use inside the graveyard. You can discover this symbol by going to the Native village with a monument with a giant hammer (B11). The symbol is on the head of this giant hammer. Alternatively you can ask Yngwar to sketch the symbol on a piece of leather.
3) Find the crank inside the graveyard. Its location is random for every game. It can be on the ground, leaning against a wall or already inserted into a hoist. The best way to get the bone crank is:
a) Wear AGI and +movement speed gear
b) Keep pressing Tab/Z to see if the crank is resting on a wall/on the ground
c) Click on every Hoist when you walk pass it. If the bone crank is already inserted it'll pull up a corpse. You'll just have to right-click to take it out

What NOT to do inside the graveyard:
a) stealing stuff, opening container (even without taking anything), searching inside a crypt (again, even without taking anything) will anger the ghost there. They'll spawn and attack you with unavoidable electrical based damage just like a Doppleganger. However you can't kill the ghost w/ Energy weapons/Neural Overload/Eternal torch.
b) Brute force searching a corpse without knowing the specific body part from Ferryman/Yngwar. The ghost will show up and attack you if you try searching too many times/stayed too long

Once you have the shard you can turn it into the Eternal Torch by:
1) asking Azif for help
2) drink the Juice and do it yourself by examining the shard

Convincing Todd
Stig - you need to read Todd's medical record + Hormone test results on the computer first, than the correct dialogue options are:
4. Keeping him in one dome is going to be more stressful in the long run
1. He needs more space.
2. I know how implants work. I'll make sure he does fine.
5. He shouldn't live in constant fear of everything.
4. I'll take care of it if it happens. He'll see everything can be overcome.

Angus - find tool bracer and have it in inventory - correct dialogue options:
2. I found this bracer in the machine shop.
1. Could you show me how it works?
1. So how do you use it?
1. Can I try the tool bracer on?
1. I just want to see how it feels.
2. Put it on and wait.
2. Uh ... What?
2. How do I press on it?
5. What do you mean, "move up"?
2. Move you whole arm up.
1. Move your hand up.
3. Now what?
2. Move your hand up again.
1. It's a miracle Todd learned how to use the tool bracer with you around.

Shelley - there are two motion paintings, you need to look at both of them before talking to her. Shelley have ♥♥♥♥ loads of dialogue options, just keep picking any option you didn't choose before. It's long but you'll eventually convince her.

End of Spoiler
Crafting & component reference part I
The wiki has a detailed explanation for crafting[stygiansoftware.com].
You can boost your effective crafting skills using the workbenches[stygiansoftware.com] in your house which provides a 15% bonus. Hypercerebrix provides +2 to INT.

Crafting requirement for medicine at a glance:
If the tool tips does not mention cool down for a specific drug that means it has no cool down. However, you can only gain +10 MP once per turn for Jumping Bean.

Ammo/Utilities/Traps/Others crafting requirement at a glance:
Note: Shotgun shells mechanics requirement depends on quality of component used.
Note: ~ = skill level needed depends on component quality. Q78 Chemical Blob Dispenser = lowest tested component for Chemical Blob Trap MKIII.
Note: minimum electronics = 50 for regular version of Spying Endoscope, expect 65+ electronics for night vision Spying Endoscope.

The following table list the highest quality of all crafting components I was able to obtain over multiple play-through. I used the duplication and item transfer trick and created a super crafting save. This table will give you a rough idea of a best case scenario but such high quality components are probably not obtainable without cheating and/or VERY heavy grinding. I will also list some commonly crafted items and their respective skill requirement.
Note: highlighted line in yellow = changes since last guide update

Top quality of components on sale after successful completion of Depot A = roughly around Q100, from Marty in Core City
Top quality of components on sale after completion of Core City Faction quest-line without Mercantile = roughly around Q130 ~ Q140, depends on merchant
Top quality of components on sale after completion of Core City Faction quest-line with 105 effective Mercantile = roughly around Q164, depends on merchant
Top quality of components spawn as randomly generated loot in final area = Q188

Max theoretical quality for artificial components (i.e.: sniper frame) for sale before final area (which exclude natural material) = Q175
Crafting & component reference part II
Skill requirement:
Acid Collector
Aluminized Cloth
Ancient Rathound Leather
Assault Rifle Frame: Chimera
Assault Rifle Frame: Hornet
Assault Rifle Frame: Huszar
Assault Rifle Frame: Marauder
Biohazard Vest (component)
Black Cloth
Blast Cloth
Boot Spring
Burrower Carapace
Cave Hopper Leather
Ceramic Plate
Chemical Blob Dispenser
Circular Wave Amplifier
Crossbow Parts: Cyclon
Crossbow Parts: Hurricane
Crossbow Parts: Monsoon
Crossbow Parts: Tornado
Crossbow Parts: Zephyr
Cryogenic Collector
Electromagnetic Deflector
Electromagnetic Field Stabilizer
Electroshock Generator
Galvanic Foam Padding
Galvanic Vest (component)
High Density Foam Padding
High Efficiency Energy Converter
High Frequency Shield Modulator
Incendiary Collector
Infused Ancient Rathound Leather
Infused Cave Hopper Leather
Infused Mutated Dog Leather
Infused Pig Leather
Infused Rathound Leather
Infused Siphoner Leather
Insulated Vest (component)
Insulating Foam Padding
Crafting & component reference part III
Skill requirement:
Kevlar Cloth
Laminated Fabric Ballistic Panel
Laser Emitter
Low Frequency Shield Modulator
Medium Frequency Shield Modulator
Metathermic Modulator
Motion Tracking Lens
Mutated Dog Leather
Nanocomposite Plate
Pig Leather
Pistol Frame: Falchion
Pistol Frame: Hammerer
Pistol Frame: Hawker
Pistol Frame: Neo Luger
Plasma Core
Plasma Discharger
Pneumatic Hammer
Proximal Neuroscopic Filter
Psi Beetle Carapace
Psionic Mufflers
Psychokinetic Modulator
Rathound Leather
Regenerative Vest (component)
Reinforced Fabric Ballistic Panel
Seeker Lens
Serrated TiChrome Blade
Serrated Steel Blade
Serrated Tungsten Steel Blade
Shield Capacitor
Siphoner Leather
Smart Lens
Smart Module
SMG Frame: Impala
SMG Frame: Jackrabbit
SMG Frame: Jaguar
SMG Frame: Steel Cat
Sniper Rifle Frame: Corsair
Sniper Rifle Frame: Harbinger
Sniper Rifle Frame: Reaper
Sniper Rifle Frame: Spearhead
Crafting & component reference part IV
Skill requirement:
Soft Foam Padding
Stable Neural Amplifier
Steel Spikes
Steel Plate
Sturdy Vest
Super Steel
Thought Control Modulator
TiChrome Bars
TiChrome Spikes
Tungsten Steel Plates
Tungsten Steel Spikes
Universal Psionic Modulator
  • Rathound leather Q44 - from Rathound/Rathound alpha, Q74 from Augmented Rathound. Without Skinner feat, they (Q44/Q74) both grant 11% critical chance as infused rathound leather armor. With Skinner Q74 Rathound leather = 14% critical chance leather armor.
  • Don't bother hunting cave hopper for cave hopper leather, just loot them from Cave Hopper Cemetery.
  • For your early game, Marty[stygiansoftware.com] is a reliable source of high quality crafting components (around Q100).
Crafting & component reference part V
Clothier, Skinner, Gun Nut, Power Management, Skinner, Weaponsmith, Bowyer, Ballistics, Practical Physicist, and Mad Chemist will grant their respective bonus with no impact on skill requirement. Skinner will not increase quality when crafting infused leather, but will confer a bonus when using the infused leather as a crafting component.

I will list the highest possible skill requirement to give you a rough idea on how high you should level your crafting skills. Again I must stress the fact I'm presenting the best case scenario here; you probably will not have such high quality crafting components without cheating and/or VERY heavy grinding.

Assault Rifle
Relevant wiki article (contains AP cost table showing AP using rapid reloader): Assault Rifle[stygiansoftware.com]
Burst rapidly fires five bullets with reduced precision, seven bullets with full-auto. Muzzle Brake adds 2 extra bullet per burst, thus 2/5 * 100% = 40% increase in damage; 2/7 * 100% = 28.5% increase in damage. Suggested optional parts: Rapid Reloader/High Resolution Digital Scope + Muzzle Brake.
Highest skill requirement (Assault Rifle Frame: Marauder, High Resolution Digital Scope): Mechanics 173, Electronics 50
Highest skill requirement (Assault Rifle Frame: Marauder, Smart Module): Mechanics 173, Electronics 145

Relevant wiki article: Balaclava[stygiansoftware.com]
Fabric only, leather not accepted.

Highest skill requirement (Black Cloth): Tailoring 142

Relevant wiki article: Boots[stygiansoftware.com]
Melee char should use Tabi boots instead as the special effect of reducing 1 AP for all melee attacks is just too good. Bladed and spiked boots might look good on paper but suck in practice.

Check out the various Infused leather articles[stygiansoftware.com] for their special bonuses.

Highest skill requirement (Infused Heartbreaker Serpent Skin, High Density Foam Padding, Steel Plates): Mechanics 162, Tailoring 150, Biology 31

Chemical Pistol
Relevant wiki article: Chemical Pistol[stygiansoftware.com]
Highest skill requirement (Incendiary Collector): Chemistry 151, Mechanics 26

Cloaking Device
Relevant wiki article: Cloaking Device[stygiansoftware.com]
Highest skill requirement (Plasma Core): Electronics 148

Combat Gloves
Relevant wiki article: Combat Gloves[stygiansoftware.com]
Leather combat gloves have 12 base AP cost and lower damage compare to metal gloves. Gloves crafted with infused leathers offer no special bonuses but you should still craft them using infused leather as the damage scale directly with quality of leather used as glove material.

Metal gloves have 16 base AP cost and higher damage compare to leather gloves. Damage scale directly with quality of metal used for glove material with no difference between different types of metal.

Metal plate enhancement will increase base damage based on metal quality, with no difference between different types of metal, not recommended.

Metal blade enhancement will always provides 35% chance to inflict a bleeding wound that deals additional x% damage over 3 turns. % of damage scale directly with quality of metal used with no difference between different types of metal, recommended.

Metal spikes enhancement will always provides a secondary hit that deals small amount of Mechanical damage. Damage scale directly with quality of metal used with no difference between different types of metal, not recommended.

Electroshock Generator - secondary hit that deals an extra Electricity damage on primary target and half of that to nearby targets, not recommended. You should crafted and use a knife w/ energy edge as optional part instead to deal w/ high mechanical resist targets.

Pneumatic Hammer - every fourth hit deals additional x% damage and incapacitates the target for up to 3 turns. Damage scale directly with quality of Pneumatic Hammer used, highly recommended.

Highest skill requirement for leather gloves
(Infused Infused Heartbreaker Serpent Skin, Serrated Tungsten Steel Blade, Pneumatic Hammer, Plasma Core): Tailoring 124, Biology 31, Mechanics 172, Electronics 172
(Infused Infused Heartbreaker Serpent Skin, Serrated Tungsten Steel Blade, Electroshock Generator, Plasma Core): Tailoring 124, Biology 31, Mechanics 158, Electronics 177

Highest skill requirement for metal gloves
(Steel plate, Serrated Tungsten Steel Blade, Pneumatic Hammer, Plasma Core): Mechanics 172, Electronics 175
(Steel plate, Serrated Tungsten Steel Blade, Electroshock Generator, Plasma Core): Mechanics 161, Electronics 177

Combat Knife
Relevant wiki article: Combat Knife[stygiansoftware.com]
Quality of the metal determines damage potential and durability; type of metal determines base AP cost, crit chance, crit damage bonus and % of energy shield bypass. I'm too lazy to list them all here so please consult the wiki for combat knife[www.underrail.com], dagger[www.underrail.com], serrated knife[www.underrail.com].

As a knifer you want bleeding, low AP cost or high critical chance and bonus so you want to use Energy or Shock Serrated Tichrome/Tungsten Knife.

Against robot, you want to use Shock TiChrome Combat Knife. Energy knife is completely ineffective against Naga Protectors.

Highest skill requirement (Steel plate, Electroshock Generator, Plasma Core): Mechanics 147, Electronics 177

Relevant wiki article: Crossbow[stygiansoftware.com]
You want critical damage bonus so Anatomically-Aware Scope is a no brainer, use Pneumatic Reloader for your fast crossbow and Super String for your heavy hitting crossbow. Base damage scale directly with quality of basic crossbow parts used.

Highest skill requirement (Crossbow Parts: Tornado, High Resolution Digital Scope): Mechanics 150, Electronics 30
Crafting & component reference part VI
Energy Pistol
Relevant wiki article: Energy Pistol[stygiansoftware.com]
There are three types of energy pistols: Laser Pistol, Plasma Pistol, Electroshock Pistol. Energy pistols have a higher AP cost compare to regular pistol due to the fact Gunslinger does not affect them, and you cannot use a rapid reloader enhancement. As explained below, you should use Circular Wave Amplifier as your optional enhancement on energy pistols.

Laser Pistol - low AP cost and low base damage, might seems mediocre at first glance. This is actually a fairly good weapon if you can reliably crit (ambush, aimed shot) due to insanely high critical damage bonus.

Base critical damage bonus = 100%
Circular Wave Amplifier (quality 144) = add 179% = 279%
Practical Physicist = add 25% = 304%
Critical Power = For each 1% of weapon or unarmed attack critical damage bonus above 100%, you gain an additional 1% critical damage bonus. = add 204% = 508% (!)

Highest skill requirement (Energy pistol frame, Plasma Core, High Efficiency Energy Converter, Smart Module): Electronics 150, Mechanics 15

Plasma Pistol - energy pistol version of a sniper rifle with much lower precision and range and a very high AP cost. You can reduce the AP cost down to 25 with 17 dex by having a lower PER (translation: lower accuracy and damage from gun skill). Plasma pistol deal half of their damage as Energy and half as Heat so you can use it to overcome enemies with high mechanical resist/DT. The only thing going for it is the insanely high critical damage bonus (around 660%).

Originally posted by carashi:
Instead of having 17 Dex, you can use Point Shot feat every round. Sure, it lower accuracy, but so does lowering your Per, also it's much easier, leaves more ability points to spend and comes earlier in the game.

Highest skill requirement (Energy pistol frame, Plasma Core, High Efficiency Energy Converter, Smart Module): Electronics 148, Mechanics 15

Electroshock Pistol - On hit: There's a 50% chance that the original target is stunned for 1 turn, after which the electrical bolt jumps up to 3 times, each time dealing damage equal to 65% of damage dealt to the previous target. It can hit the same target multiple times, but needs at least two targets to jump between.
Damage per shot in an ideal case = 100% + 65% + 42.25% + 27.46% = 234.71%
As with the other energy weapons you must critically hit in order to use the electroshock pistol to its full potential.

Highest skill requirement (Energy pistol frame, Plasma Core, High Efficiency Energy Converter, Smart Module): Electronics 148, Mechanics 15

Energy Shield Emitter
Relevant wiki article: Energy Shield Emitter[stygiansoftware.com]
See the Game mechanic explained, Energy shield section. Circular Wave Amplifier and Shield Capacitor are useless so you should use High Efficiency Energy Converter as your shield enhancement.

Highest skill requirement (2X Low Frequency Shield Modulator, Plasma Core, Shield Capacitor): Electronics 194

Relevant wiki article: Goggles[stygiansoftware.com]
Four versions: Adaptive (+1 PER), Motion Tracking (detect traps and hidden enemies, essential for low PER build), Seeker (increase critical chance, range weapons only), Smart (increase ranged weapon special attack damage).

Highest skill requirement for regular goggles
(Adaptive Lens, Goggle Frame): Mechanics 20, Electronics 15
(Motion Tracking Lens, Goggle Frame): Mechanics 65, Electronics 131
(Seeker Lens, Goggle Frame): Mechanics 78, Electronics 130
(Smart Lens, Goggle Frame): Mechanics 51, Electronics 147

Highest skill requirement for night vision goggles
(Adaptive Lens, Goggle Frame, Image Intensifier Tube, Plasma Core): Mechanics 20, Electronics 167
(Motion Tracking Lens, Goggle Frame, Image Intensifier Tube, Plasma Core): Mechanics 65, Electronics 167
(Seeker Lens, Goggle Frame, Image Intensifier Tube, Plasma Core): Mechanics 78, Electronics 167
(Smart Lens, Goggle Frame, Image Intensifier Tube, Plasma Core): Mechanics 51, Electronics 167

Infused leather
Relevant wiki articles: Blueprint: Infused Leather[stygiansoftware.com] and special effects for various infused leathers[www.underrail.com]
Skinner will not increase the quality of the infused leather produced, but will grant a bonus when you use the infused leather as a crafting component.

Quality of leather and super steel fiber used does NOT affect skill requirement; it's always Mechanics 32, Tailoring 128 (and Chemistry 15 for Mutated Dog Leather)

Highest skill requirement
(Cave Hopper Leather, Super Steel Fiber): Mechanics 32, Tailoring 128
(Rathound Leather, Super Steel Fiber): Mechanics 32, Tailoring 128
(Mutated Dog Leather, Super Steel Fiber): Mechanics 32, Chemistry 15, Tailoring 128
(Pig Leather leather, Super Steel Fiber): Mechanics 32, Tailoring 128
(Siphoner Leather, Super Steel Fiber): Mechanics 32, Tailoring 128
(Ancient Rathound Leather, Super Steel Fiber): Mechanics 32, Tailoring 128

As a side note: lowest component quality tested in order to get 10% critical chance without Skinner feat: Q131 Super Steel Fiber + Q42 Rathound Leather

Leather armor
Relevant wiki article: Leather Armor[stygiansoftware.com]

Leather armor with the highest possible skill requirement
(Infused Ancient Rathound Leather, Insulating Foam Padding, Black Cloth): Tailoring 179

Highest skill requirement for other notable leather armors
(Infused Cave Hopper Leather, Soft Foam Padding, Black Cloth): Tailoring 166
(Infused Mutant Dog Leather, Insulating Foam Padding, Black Cloth): Chemistry 31, Tailoring 179
(Infused Pig Leather, Insulating Foam Padding, Black Cloth): Tailoring 179
(Infused Rathound Leather, Insulating Foam Padding, Black Cloth): Tailoring 179
(Infused Siphoner Leather, Insulating Foam Padding, Black Cloth): Tailoring 179

Metal armor
Relevant wiki article Metal Armor[stygiansoftware.com]
A note to metal combat glove/Power fist users: if you are trying to qualify for Lightning Punches while wearing a bladed metal armor your total effective armor penalty must be at 19% or below. This is possible with the following combo (without any specialization): Nimble, Armor Sloping, 1X Super Steel Plate and 1X Serrated TiChrome Blade/Serrated Steel Blade. Metal armor crafted using TiChrome Bars and/or Serrated Tungsten Steel Blade will NOT qualify.

Metal armor with the highest possible skill requirement
(4X Steel Plates, Sturdy Vest): Mechanics 192, Tailoring 133
(4X Steel Plates, Galvanic Vest (component)): Mechanics 192, Tailoring 139, Electronics 48
(4X Steel Plates, Regenerative Vest (component)): Mechanics 192, Tailoring 119, Electronics 77, Biology 77

Highest skill requirement for some notable metal armors
(4X Tungsten Steel Plates, Sturdy Vest): Mechanics 186, Tailoring 133
(4X Super Steel Plates, Sturdy Vest): Mechanics 167, Tailoring 133
(1X Super Steel Plates, Sturdy Vest, 1X Serrated TiChrome Blade): Mechanics 154, Tailoring 133
Crafting & component reference part VII
Metal Helmet
Relevant wiki article: Metal Helmet[stygiansoftware.com]
Always use a Shaded Visor when crafting a metal helmet.

Metal helmet with the highest possible skill requirement
(1X Steel Plates, High Density Foam Padding): Mechanics 147, Tailoring 150

Highest skill requirement for other notable metal helmets
(1X Super Steel Plates, High Density Foam Padding): Mechanics 128, Tailoring 150
(1X Tungsten Steel Plates, Insulating Foam Padding): Mechanics 144, Tailoring 150

Relevant wiki article: Pistol[stygiansoftware.com]
Rapid Reloader is your friend, use it as your primary enhancement. In general you want to use Smart Module as your secondary enhancement. Laser Sight is useful early game.
AP cost table (RR = rapid reloader):
5mm RR
7.62mm RR
9mm RR
.44in RR
Neo Luger

Highest skill requirement (Pistol Frame: Neo Luger, Smart Module): Mechanics 150, Electronics 145

Psionic Headband
Relevant wiki article: Psionic Headband[stygiansoftware.com]

Highest skill requirement (Temporal Manipulation Modulator): Electronics 137, Biology 48

Riot Gear
Relevant wiki article: Riot Gear[stygiansoftware.com]
Awesome early game armor type due to the fact all your enemies use melee. Tactical vest, infused leather armor, or metal armor will usually be a better choice once you are further into the game.
Riot gear with riot shield is an interesting concept on paper but not that good (only 35% chance to block) in practice. The shield will increase armor penalty (but does not increase mechanical resist/threshold) meaning lower effective dodge, evasion and stealth; to top it off carrying a shield limits the wearer to one-handed weapons! Psi Beetle has better psi bonuses than psi beetle. Burrower has the best block/armor penalty ratio. Tungsten Steel Plates shield blocks the highest amount of mechanical damage. The shield is only effective when you build spec for it and combine it with other form of blocking (parry/spear/deflection, etc).

Highest skill requirement
(Galvanic Vest (component), Super Steel Sheet, Steel Plates, Black Cloth): Mechanics 147, Tailoring 156, Electronics 48
(Regenerative Vest (component), Super Steel Sheet, Psi Crab Carapace, Black Cloth): Mechanics 128, Biology 77, Tailoring 156, Electronics 77

Relevant wiki article: Sledgehammer[stygiansoftware.com]

Highest skill requirement (Steel Plate, Electroshock Generator, Plasma Core): Mechanics 147, Electronic 177

Relevant wiki article: SMG[stygiansoftware.com]
Rapid Reloader is a must, use Muzzle Brake or High Resolution Digital Scope as your secondary enhancements.
AP cost table (RR = rapid reloader):
5mm RR
7.62mm RR
8.6mm RR
Steel Cat

Highest skill requirement (SMG Frame: Jackrabbit, Smart Module): Mechanics 147, Electronic 145

Sniper Rifle
Relevant wiki article (contains AP cost table showing AP using Rapid Reloader/Rifle Bipod): Sniper Rifle[stygiansoftware.com]
Use Rapid Reloader and Smart Modules as your enhancements.

Highest skill requirement (Sniper Rifle Frame: Corsair, Smart Module): Mechanics 165, Electronic 145

Tabi Boots
Check out the various Infused leather articles[stygiansoftware.com] for their special bonuses.
Relevant wiki article: Tabi Boots[stygiansoftware.com]
A melee char should wear tabi boots 99% of the time due to the AP -1 for melee attack buff.

Highest skill requirement (Infused Heartbreaker Serpent Skin): Tailoring 124, Biology 31

Tactical Vest
Relevant wiki article: Tactical Vest[stygiansoftware.com]
A good armor for all early game char and especially useful for psi users due to Psi Beetle Carapace armor plate.

Highest skill requirement
(Sturdy Vest, Super Steel Sheet, Psi Crab Carapace, Black Cloth): Mechanics 128, Biology 31, Tailoring 156
(Galvanic Vest (component), Super Steel Sheet, Ceramic Plate, Black Cloth): Mechanics 139, Tailoring 156, Electronics 48
(Regenerative Vest (component), Super Steel Sheet, Ceramic Plate, Black Cloth): Mechanics 139, Biology 77, Tailoring 156, Electronics 77

Relevant wiki article: Taser[stygiansoftware.com]
Taser is an excellent source for stun. I would recommend a low quality electroshock generator to lower your energy cost. A quality 151 electroshock generator will deal 26-47 electricity damage once every three turns, hardly anything to write home about.

Highest skill requirement (Plasma Core): Electronics 148
Crafting & component reference part VIII
Expansion Content - Crafting

Infused leather
Relevant wiki articles: Blueprint: Infused Leather[stygiansoftware.com] and special effects for various infused leathers[www.underrail.com]
Skinner will not increase the quality of the infused leather produced, but will grant a bonus when you use the infused leather as a crafting component.

Quality of leather and super steel fiber used does NOT affect skill requirement; it's always Mechanics 32, Tailoring 128 (and Chemistry 15 for Mutated Dog Leather or Biology 10 ~ 31 for Heartbreaker Serpent Skin, Leper Serpent Skin and Sea Wyrm Scales)

Highest skill requirement:
(Bison leather, Super Steel Fiber): Mechanics 32, Tailoring 128
(Great Siphoner Leather, Super Steel Fiber): Mechanics 32, Tailoring 128
(Heartbreaker/Leper Serpent Skin/Sea Wyrm Scales, Super Steel Fiber): Mechanics 32, Biology 31, Tailoring 128

Leather armor
Relevant wiki article: Leather Armor[stygiansoftware.com]

Leather armor with the highest possible skill requirement
(Infused Heartbreaker Serpent Skin, Insulating Foam Padding, Black Cloth): Tailoring 166, Biology 31

Highest skill requirement for other notable leather armors
(Infused Bison Leather, High Density Foam Padding, Black Cloth): Tailoring 179
(Infused Great Siphoner Leather, High Density Foam Padding, Black Cloth): Tailoring 179
(Infused Heartbreaker Serpent Skin, High Density Foam Padding, Black Cloth): Tailoring 179, Biology 31
(Infused Leper Serpent Skin, High Density Foam Padding, Black Cloth): Tailoring 179, Biology 24
(Infused Sea Wyrm Scales, High Density Foam Padding, Black Cloth): Tailoring 179, Biology 11

Highest skill requirement (Steel Plates, Electroshock Generator, Plasma Core): Mechanics 147, Electronics 177

Short Shotgun Barrel = Spread angle:(+5 long barrel angle), Precision: (-10% long barrel value)
Long Shotgun Barrel = Damage: (~83% short barrel damage)

Forward Grip = +10% burst precision for combat shotgun, -5AP per shot for regular shotgun
Shotgun Choke = Spread angle -10, damage * 85%
Shotgun Tube Extension = +3 magazine capacity

Highest skill requirement (Shotgun Frames: Despot): Mechanics 169

Highest skill requirement (Steel Plates, Electroshock Generator, Plasma Core): Mechanics 147, Electronics 177

Energy Edge Emitter (EEE) - adds energy (0.90 to 1.20 * EEE Quality) damage to spear when powered, but also permanently reduces spear mechanical damage by 10%.
Electroshock Generator (EG) - adds electrical (roughly 0.37 to 0.75 * EG Quality) damage to spear to primary target when powered. In additional, all enemies standing next to primary target will receive half of primary electrical damage.

*Spoiler alert for the next two sections: Final Area - you have been warned.*

Final area *endgame spoilers* part I
Version 1.0.3 increases the rate of increase for creeping dread/eye of tchort on dominating difficulty; some of the tips listed below might not work (or work as well) if you are playing on dominating.

New players frequently complain about the endless spawning enemies in the final area.

Tchortlings won't spawn until you have the eye of tchort debuff - so you are safe up to 20 stacks of creeping dread (CD). It is very important to talk to Leo soon after you enter Deep Caverns. He not only gives you info and hints about the surrounding areas, but most importantly he teaches you a passive feat which will slow down Creeping Dread and delay the onset of the Eye of Tchort.[stygiansoftware.com] You can get rid of CD by going down safe spots[stygiansoftware.com]. If you do this technically you only ever have to fight one single tchortling before meeting the final boss.

Arke powergrid
Unfortunately you don't have enough power to power up all buildings at the same time (Styg, why? This design choice doesn't enhance the game in any way!). Suggested power allocation: Warehouse Block 2 + Mutagen Tanks A + Caerus Residential Block. Reset power allocation once you visited Warehouse Block + Caerus Residential Block to: Research Complex + Mutagen Tanks A. This means you only have to backtrack once.

Deep Caverns Faceless
You need three previous friendly acts in order to be friendly w/ the Faceless down in DC, two acts = neutral, one acts or less = hostile.
Rail Crossing - enter Buzzer's shop, second floor, allow the mindreader to scan your thoughts, allow them to leave Rail Crossing without further violent.
  • Killing Faceless (except mindreader) + their robots in Rail Crossing = no change, comfirmed in a ver 1.0.3 dominating game.
  • Convince mindreader to leave Buzzer alive = no change
  • Originally posted by hilf:
    You can kill all but mindreader and still hold hands with Faceless in DC.

Foundry - successfully completed Faceless recon[stygiansoftware.com] by discovering and telling the Faceless group the truth.
  • Fighting and killing Faceless near Foundry = ??? Based on patch notes it seems this will cause the mindread in DC to fail - unconfirmed.

Core City - set the injured Faceless[stygiansoftware.com] free and offer healing supply.
  • Fighting and killing Faceless at various points of blockade = fail mindread in DC
  • Fighting and killing Faceless within the Institute of Tchort, outside the elevator = ???
  • Fighting and killing Faceless within West Wing = ???
  • Fighting and killing Faceless in the elevator fight = no change, confirmed in a ver 1.0.3 dominating game

Being friendly w/ the Faceless is pretty meh, you only get some ammo and medical supplies from them. Being hostile is a pain in the ass due to their endless respawning stealthy Faceless Gaunt. Seriously being hostile w/ Faceless in DC is a pretty miserable experience. If you *must* fight Faceless in DC (i.e.: want to farm their oddities) I would suggest you wipe out their base + their patrols right before fighting Tchort. A safer but much more tedious way to farm their oddities would be killing them w/ mines in an uncontrolled zone (not recommended, believe me I tried it).

Originally posted by Altos:
If you plan on cooperating with both the Tchortists and the Faceless in the Deep Caverns (for maximum access to shops, ammo, meds, warehouse, lore, etc.), it is critical that you speak to the Faceless Commander and ally yourself with the Faceless before talking to the Tchortists. This is especially important if you plan on accepting the "Scout Faceless Positions" quest for Harmost Stavros (which gives you access to more supplies and a gate part), because if you accept this quest before talking to the Commander and having your mind read, the entire base will go hostile and you'll lose any chance of redemption, making your trek through Deep Caverns infinitely more difficult.

See Get into Cytosine Outpost[stygiansoftware.com]. It's recommended to be friendly w/ the Tchortist as they offered the best trader[stygiansoftware.com] in Deep Caverns. Leo[stygiansoftware.com] is another Deep Caverns trader but his selection is not as good. It's still possible to be friendly w/ Tchortist down in DC even if you are previously hostile to the Institute.
Final area *endgame spoilers* part II
It's very easy to get lost in DC, the worst offender being the Labyrinth of Deep Caverns. Personally I used Happy Dahaka's maps (Caves + Labrynth (worms)).

Defeating Tchort
Regenerative armor, regenerative mixture and focus stim help but are not required. Your objective is to destroy the eye of Tchort. The eye has 2000 HP, regenerates 200 hp per turn (can be slowed down), insanely high mechanical resistance and threshold, high bio resistance and threshold, and immunity to fire on the floor (but not immune to fire damage)[stygiansoftware.com]. All guns should be fully loaded w/ W2C ammo.

You can block the passageway leading to Tchort using Tchortling Sower tentacle wall
Originally posted by SubterminalOptimization on March 22, 2018, on the official forum:
You should know that the tentacle wall I showed in my previous screenshot (A) was an amusing/unusual one that I just went ahead and used. However, for my data gathering (where I had to repeatedly kill the Eye at Level 10 from the same mid-map save) I confirmed that by far the more consistent/reliable positioning is the one where you only need a single square to be blocked. You actually want to stand right next to the tentacle-hole (even if you have more movement points) and specifically wait there for the sowers to shoot at you. The outcome will look like this: (screenshot B)
Screenshot A:
Screenshot B:

Strategy for various builds
Pistol - ignore mutagen puzzle & tanks, approach Tchort under stealth, aimed shot w/ a sniper rifle/plasma pistol, adrenaline shot, rapid fire finish w/ .44 pistol. This is possible w/ crafted gear aiming for high critical chance and critical bonus.

SMG - ignore mutagen puzzle & tanks, charge in and burst.

Assault rifle - ignore mutagen puzzle & tanks, charge in and burst.

Sniper - ignore mutagen puzzle & tanks, enter area under stealth, one shot Tchort using snipe/aimed shot.

Throwing - solve mutagen puzzle, destroy the four mutagen tanks w/ TNT under stealth. Unfortunately some throwing knives build is just not viable against Tchort due to the insanely high mechanical threshold & resistance.
Ideal loadout is Incendiary Grenade + cave ear throwing knives + leper/heartbreak throwing knives. After you TNT all 4 tanks head back to the room near the ladder. Use this room to take out all Tchortlings and then focus on tentacles. I managed to take out two tentacles inside that room before engaging Tchort (the last one won't move for some reason). Walk toward Tchort - mine/burn/caltrop the passage once you are through. Remember to take out all tentacles before tackling Tchort. Use throwing knives on Tchort and poison your way to victory. Ensure the passageway is burning at all times or the tchortlings will be a problem.
Demolition expert - quick tinker HE mine near Tchort, move away, detonate mine w/ HE grenade, poison throwing knives while waiting for mine and grenade cool down, rinse and repeat.

Crossbow - if you have 75 chemistry you can craft corrosive acid bolt and follow Altos' advice:
Originally posted by Altos:
And Tchort was actually a joke, too. I just ignored the tentacles, never destroyed the four tanks, and focus-fired Tchort with Corrosive Acid bolts until he exploded. Since I rushed the Eye, the Tchortlings never even caught up to me.

Crossbow - if you don't have 75 effective chemistry you should solve the mutagen puzzle. Destroy the four mutagen tanks w/ TNT under stealth. Quick tinker a massive HE mine field near Tchort and detonate it using HE grenade.

Originally posted by carashi:
Took out 2-3 mutagen tanks, put bear and acid traps to block Tchortlings and then start throwing electrical bolts at Tchort. You just need to take out psionic tentacle first, attacks of the rest your shield will probable be able to take. Took me 5-6 turns with the use of focus stim.

Melee - expose weakness is your friend. It's possible to destroy Tchort within one turn depending on your gear and build. If you are having trouble, solve mutagen puzzle and destroy the four tanks under stealth using TNT.

Stealth Tranquility psi - follow st88's advice:
Originally posted by st88:
Tchort died in one turn. No mutagen tanks destroyed, mutagen puzzle unsolved.

I just literally walked under stealth towards it, then turned on the shield and dropped stealth.

A couple of tentacles moved and attacked, but damage was minimal.

Healed back to full HP to make use of tranquility, moved closer to Tchort.

Thermodynamic Destabilization on a tentacle next to it, Telekinetic Proxy, Implosion on the tentacle, Locus of control, mass Neural Overload, +20 AP adrenalin injection, one more Neural Overload to finish the tentacle — tentacle explodes, Telekinetic Punch to finish Tchort.

No lucky crits involved. Perfectly reproducible. Used one psi booster.
note Sep 9, 2020: Thermodynamic Destabilization is now capped at 100% HP so it's probably no longer a good move under the new psi system.

Stealth Psychosis psi - follow hilf's advice:
Originally posted by hilf:
Minmaxed Psychosis psion can just use Trance + Mental Breakdown + maniaed Neural Overload for one hit KO:
note Sep 9, 2020: Just tested and confirmed still works under the new psi system.

*End of spoilers*

*end of spoilers*
Stretching graphics to help see game better
elmo was able to keep the monitors at 1920x1200 resolution, but keep the game in windowed mode at the lowest resolution of 1024x768(4:3). Detailed are posted on this Steam thread.
Cheat engine
I use cheat engine (speedhack + unlimited carrying weight) with Underrail and it vastly improved my Underrail experience. I use double speed for normal gameplay, normal speed for some stealth section and 5X speed for merchant run.

Originally posted by Version patch note:
Added the ability to speed up the game while out of combat
"+" key to Speed Up
"-" key to Slow Down
or you can click the lower left corner arrows

Originally posted by Version patch note:
Changed the required amount of scraps when creating a repair kit to 40 (up from 20) per stack
Changed the weight of repair kits to 1 and advanced repair kits to 2 (up from 0.25)

I understand the above changes intended to "balance" game play so player won't be swimming in money, but the weight changes are simply uncalled-for. 4X previous regular repair kit weight and 8X previous advance repair kits weight that will not improve the game play in any way. In fact, this weight change hurts game experience by making it more tedious. Underrail is currently moving toward a direction I don't like: the devs seems to mistaken tedious and annoying mechanic as a fun/strategic/challenging experience. I would recommend trying the vanilla inventory weight limit system for your first few games and than just use unlimited carrying weight.

I uploaded the cheat engine table to MEGA and you can download it here[stygiansoftware.com].

Here's a short how to use cheat engine
- download cheat engine + cheat engine table
- open Underrail as normal, load your saved game
- open cheat engine, click on "select a process to open, select underrail.exe
- still using cheat engine, click on File -> Load -> select the cheat engine table
- still using cheat engine, click on the square at the lower left corner right under "Active". You should see "Description" besides "Active"
- still using cheat engine, click on "Enable Speedhack", adjust desired speed
- switch back to Underrail, drop any item from your inventory
- enjoy unlimited carrying weight.

Kachajal also released a more user-friendly Underrail speedhack[stygiansoftware.com] on the official forum.

Quantum posted a more detailed Underrail Cheat Engine Guide on how to cheat your characters stats, skills and perks here.

Csimbi posted a CE table on the FearLess Cheat Engine forum with extensive cheat options such as char gen editor, god mode, infinite psi, unlimited carry weight, forced merchant refresh, and more. Personally I never used that table so you'll have to ask at the FearLess forum if you have question and/or need support.

If you get a system message stating Cheat Engine has expired check and see if you system date is April 1. (Spoiler: it's an April's fool joke)

bye also published a Steam guide on How to edit/respec feats.

I encountered one issue using cheat engine playing the final mission for Protectorate. When you gas the Free Drones base playing at 2X speed, the gas will reach you before Mareth's speech is over. You will turn into a mutant and the mutation is irreversible.
Duplication and item transfers
Direct quote from ihavefuzzylogic from this thread and additional response in this guide:
Originally posted by ihavefuzzylogic:
I haven't seen this anywhere else. You can duplicate or transfer items between characters. All you need is two saves with characters in the same room. They don't need to be the same character/game run. Put everything you want to dupe or transfer in a pile or container. I like the locker in the private room of the SGS facility. Then copy the global file from the save you want to get the new items to the transfer save. This is your character file. Take everything you want and save either in the dupe/transfer slot or a new slot if you want to keep a universal transfer save for all characters. Copy the global back to original game save and you have all items. Duping is just transferring the global into/out of the transfer save over and over.

Originally posted by ihavefuzzylogic:
Alternative instruction
You need at least 2 saves. A character save and a transfer save with the items in a container or pile. You want to copy the Global file from the character save to the transfer. The character save must be on the same save area as the transfer container or the game won't load properly. It will load the level but the character will be somewhere else. When you load the save you will have the item container and the character you want to receive the items. Your choices at this point are to take the items and save or to re-add the items to the container to increase your item amounts and save over the transfer. When finished, make a save with everything in your characters inventory and copy the Global from that save back to the original character save.

Tested and can confirm this works.
WARNING: backup your saves in a separate folder before using this trick because if you mess up you can irreversibly destroy your saves!

How to duplicate items, now with pictures:
So I'm going to duplicate some high quality components from my shotgun char, Seminome (source), to my super crafting save file, named Global (receiver).
Move both char to the same map and save. I chose my house's basement for this purpose. I now have two save files named Seminome & Global
Backup all relevant saves
You can see my high quality components are in the inventory of my (source) shotgun char and saved to "Seminome"

Now open up the Underrail save file location and open the folder for the receiver char. In my case, I want to dup items from Seminome (source) to Global (receiver), therefore I open up the Global save file folder. Cut the "global.dat" file to somewhere safe, we'll need this file later.

Open up the save folder for the source char, in my case, it's Seminome. Copy the "global.dat" file from Seminome

and paste the aforementioned "global.dat" to Global (receiver)

Now load the save file "Global" (receiver) in game

Drop everything you want to duplicate to the floor, and save to the receiving char's save file. In my case, I save to "Global".

Now go back to your Underrail save file folder and open the receiver folder, again, for me it's "Global", and delete "global.dat"

Cut and paste the original receiver "global.dat" back to the receiver's save folder.

Load the receiver save file (Global) in game.

Pick up the duplicated items from the floor and enjoy.
Depot Downloader and version rollback (Steam users only)
You can rollback your Underrail to any previous version, follow the instructions from here[stygiansoftware.com].
epeli's underrail.info
http://underrail.info (previously underrail.info.tm) is epeli's fansite for info and tools that can't be hosted on the game's official wiki.

underrail.info/build/ - super useful build tool

underrail.info/mutagens/ - helper for the mutagen puzzle, make sure you check "Disable unusable reagents" and "Atom highlighting" before you validate your reagents

You can check out his official thread[stygiansoftware.com] for tool explanations, updates and provide feedback.
< >
destroyor  [author] Jan 8 @ 4:04pm 
@Karvev - I tested it on dominating difficulty and it's fine. You'll get roughly around 70 ~ 80% xbow THC once you turned on your night vision goggles. Because it only cost you 14AP to fire a bolt you can afford to miss. You can also use flashbang and/or stun to lower enemy evasion to zero. If you are really concern about xbow accuracy, the alternative would be to just forgo xbow and wield a sniper rifle instead. However that would mean you no longer have stun on demand via. shock bolt and sniper rifles have a higher AP cost. I'm writing the pistol char build section right now but I'll rework the shotgun + xbow section when I'm done.
Karvev Jan 8 @ 1:51am 
Regarding that shotgun+crossbow psi build-how are you supposed to hit anything with bolts, since PER is not maxed and the effective crossbow skill gets up to the ~120 only at the lvl 20, shouldn't evereyone just evade those attacks?
destroyor  [author] Jan 7 @ 4:25pm 
@cheesiest cheeto - you are welcome. :) Glad this helped you.
cheesiest cheeto Jan 7 @ 2:00pm 
Thank you so much!
destroyor  [author] Dec 1, 2020 @ 5:53pm 
@sweet prince: Persuasion and Lockpicking are useful but not essential; even if you skipped them you won't missed a large part of the game. You can take my tweaked build and take all the points from pickpocketing + some points from stealth for either persuasion OR lockpicking. In general you want to allocate non-combat skill that will play to the build's strength: high WIL = Persuasion, high DEX = lockpicking/pickpocketing, high INT = hacking and so on ...

If you are trying to adjust Koveras' Assault Rifle / Thought Control hybrid into a SMG build that would be a very bad idea. SMG need high DEX to reduce their base AP cost so you need to start from scratch if you want to play SMG with no psi; you can use suggestions from this thread: https://old.reddit.com/r/underrail/comments/jk1crm/are_smgs_any_good/
destroyor  [author] Dec 1, 2020 @ 5:46pm 
Ultimately tho I recommended Koveras' build as first Underrail build because:
1) It's relatively straight forward, easy to setup and use - use AR burst + Psi manic Neural Overload to kill stuff
2) No glaring weakness except for being a 3 CON build (can be mitigated by wearing sturdy vest tac vest). The old tin can AR is hard countered by npc's bilocation and neural overload. In addition, with expedition DLC there are lot of enemies with non-mechanical/energy damage type which will bypass your metal armor. Tin can AR is still viable by crafting and wearing specific type of armor against specific type of enemies, which isn't exactly newbie friendly.
3) A common complaint for tin can AR is that it's boring. Koveras' at least mix things up with Neural Overload.

I'll try to see if I can squeeze in a more detail update re:build this weekend ... no promise tho.
sweet prince Dec 1, 2020 @ 10:58am 
Thanks, I'll try to adjust the build a bit then. I was concerned about these two specific skills because, in most RPGs, lockpicking and persuasion are pretty essential. Not sure about this one though.
fruit flavored ENERGY DRINK Dec 1, 2020 @ 3:35am 
Assuming you're on normal difficulty on your first playthrough, you could most likely get away with getting more than the usual amount of non-combat/roleplay skills. If you're going to use optimal builds you got from here then I wouldn't worry too much about combat. Just make sure your character isn't a one-trick pony in fights and you'll do fine.

Tho I wouldn't recommend getting all non-combat skills since that can be counter-productive. As in there's often multiple ways to do an objective but having all the options instead of some of them often doesn't change the outcome.
sweet prince Dec 1, 2020 @ 2:46am 
Hey. First of all, very helpful guide. Great work man!

I am thinking about starting my first playthrough with Koveras' Assault Rifle / Thought Control hybrid but I'm a little concerned about lack of Persuasion and Lockpicking skills. Won't I miss a lot because of this?

Would ditching the PSI part and going full SMG with Persuasion and Lockpicking be a good idea?
destroyor  [author] Sep 29, 2020 @ 10:54pm 
@Officer Hotpants - glad to hear you got it; duplication is always confusing for a new player.