Abyssal Horror Miniboss (Mod): Quest Walkthrough

A short guide on navigating the Abyssal Establishment quest that comes with the Abyssal Horror monster mod, created by A Slightly Startled Seal & Dismas, and which is necessary to activate the Abyssal Horror as a wandering miniboss in the Cove.

Introduction

This is a sort of companion piece to the Abyssal Horror Miniboss mod which (eventually) adds a new wandering miniboss to the game, specifically to the Cove. This also serves as a continuation of writing walkthroughs for the quests linked to Seal & Dismas' minboss creations, as I am starting to suspect there will be one roaming each base game region (Ruins/Warrens/Weald/Cove) before they are done with the whole matter. The Horror itself is a very tough foe who will provide a hell of a challenge for those Estates looking for one, and I personally feel it to be a notable difficulty spike up from the Lumberjack who preceeds it. This guide will cover the Abyssal Establishment plot quest in which you first face it: the map layout, what you can expect to find within it, the teams I've used to face it in my test runs of the mod, and what sort of strategies would work well against it.

You can check out and download the Abyssal Horror Miniboss mod here; you can also read what the mod does and the rewards for beating it:

https://steamcommunity.com/sharedfiles/filedetails/?id=1938759986

Gearing Up

For the most part, this quest is a standard Medium Champion Cove quest; it is formally a 100% Room Battle quest. Therefore, whatever you have been doing to deal with Champion Cove up to this point will help to get you through this:
- Blight & Stun
- bonus DMG against Eldritch and Unholy
- Armor Piercing & PROT debuffs for getting past the defenses of Uca Savages/Pelagic Champions/Armored Maggots
- anti-Stress measures: Stress healing, -%Stress
- anti-Disease measures in Camp: Plague Doctor, the Grave Robber's Snuff Box
- anti-Bleed measures: Battlefield Medicine, Bandages, Bleed resistance
- Corpse-clearing measures to restrict the Ghasts
- Crusaders, Shieldbreakers, Plague Doctors, Occultists, and Abominations in general, as each ticks some of the above boxes

While your Provisions will mostly be your standard pack for Cove trips, there are three different details to consider:
- you will want to stock up on Antivenoms for the Horror
- while Laudanums are standard for Champion Cove because of Ghasts, you will want to pile on a little more than usual if you have the space, also because of the Horror
- you will need at minimum three Shovels to fully navigate this map

The Map & Walkthrough

There are two major factors differentiating this quest from your standard walk in the Cove:
- the map layout for this dungeon is static,
- although the enemies and Curios you find will be RNGed, their locations, as well as the locations of Traps and Obstacles, are static

Be aware that things that affect enemy encounters in the game, like DLC and certain other mods, can also affect this quest; for example, there is a mechanic from Crimson Curse that can make an appearance here. Though untested, I imagine that Crimson Court enemies (if the Infestation level's high enough), as well as the Shieldbreaker's snakes post-nightmares, can also appear here.

The Room Curios found seem to be biased towards Fish Idols and Ship's Figureheads, so make sure to bring a couple Holy Waters and lean towards Camping late in the quest. I have also found Barnacle Crusted Chests, Sacks, and Fish Carcasses here.

https://steamcommunity.com/sharedfiles/filedetails/?id=1939444574

Note the map on the above screenshot.

From the staring point, you can head north, south, or east: the one spot south has a Room Battle and thus is virtually mandatory as the first place to go; you will find a Curio and Shipwreck on the way there. Head back to the starting point and you'll have a choice between north and east.

If you head north:
- you'll find a Shipwreck and then a Room Battle; the path splits north and east again
- if you continue north, you'll make your way through a hallway battle,a Shipwreck, and an empty room; this is followed by another hallway battle, a Curio, and a Room Battle. You'll want to pause in this Room once you've cleared it
- if you continue east, you'll find two Curios and an empty room which connects you to the path detailed below

If you head east:
- you'll find a Curio and Tentacled Lurker, then an empty room
- the next hallway goes north, running you across a hallway battle and another empty room
- you'll continue north, through another Lurker and Curio, before the path turns east and into another empty room
- from here, you can go north and south; just like in the beginning of the quest, you'll have to go south first and tackle the Room Battle at the bottom. You may want to pack some extra Scouting Chance for this quest; if you land a Scout in this southern hallway, you'll find a Prisoner Room!
- head back to the empty room you came from and travel north; you'll find a hallway battle and past that, a free Room Curio

If you headed north initially, you should be at the northwest corner at the map, heading east through a hallway with a Tentacled Lurker followed by a Curio; if you headed east initially, you should be at the northeast corner of the map, heading west past a Shipwreck. Whichever corner you're at, you should Camp here and get your buffs in, as your main target is just ahead.

Whether you Camp or decide to save the Firewood for later, when you're ready, head for the central-north room. Inside...

The Abyssal Horror (and Friends)

https://steamcommunity.com/sharedfiles/filedetails/?id=1939453411

A tentacled mass of...something, the Horror is built to be a slow tank: roughly as much HP as the Champion Ruins bosses on non-Stygian difficulty, some PROT but negligible DODGE, and slow as your typical Size 2 enemy, which makes sense since it is a Size 2. Other than Move, his resistances range from average to moderate, and as you can see, its weak points appear to be Blight and Stun, which has it in line with nearly everything else in the Cove; to that end, it also is Eldritch. It comes into battle with a buff for "3 Devoured Souls"...more on that later.

This boss is very much an endurance test, a weird cross between the Miller and Crew, although in many respects it is more dangerous than either one of those, as it focuses on inflicting every DoT out there, and gets a few dubious advantages to compensate for being a slow duck:
- three actions per round
- it guaranteed-surprises you
- Torchlight is automatically set to 50 at the start of combat and cannot be raised via Torch

The Abyssal Horror uses:
- Return to Flesh: consumes one of its Devoured Souls to summon an Unformed, which occupies Rank 1 upon...er, forming. This debuffs the Horror, increasing DMG Received by 20% for seven turns, and has a seven-turn cooldown. This will always be the Horror's first action taken
- Maw of the Abyss: hits Rank 1, 2, or 3, heavy DMG, Bleeds for 5 points/round,3 rds
- Decay the Flesh: hits two targets from Ranks 2-4, small DMG (which becomes moderate DMG due to the lower Torchlight), Blights for 5 pts/rd, 3 rds
- Unearthly Knowledge: hits the entire party for small DMG, inflicts Horror for 2pts/rd, 6 rds
- Consume the Flesh: consumes one of its Devoured Souls to self-heal for 35 HP and self-Cures, clearing any DoTs and Debuffs

https://steamcommunity.com/sharedfiles/filedetails/?id=1939455125

The Unformed summon is a dedicated support enemy, in the vein of Rapturous Cultists; he has no offensive capabilities, and only exists to sacrifice itself for its master. Interestingly, he shares the Unholy/Eldritch typing as the Necromancer but unlike the latter, is resistant to DoTs and Movement, and moderately resistant to Stuns; its big weakness lies in Debuffs. It also has a fair amount of health for a Size 1, on par with the Radiant Four (Bearer/Skiver/Virago/Ghast)Once summoned, he can:
- Prayer of Protection: Guards the Horror for two rounds and buffs itself for +25% PROT and -25% CRIT Received Chance
- Prayer of Life: damages itself for varying amounts of HP, to heal the Horror and grant it Restoration for 5pts/rd, 3 rds

Fighting the Abyssal Horror

- having three actions per round makes the Horror incredibly prime Blight fodder, so you'll want to focus on that; having Stun utility is a great boon, as it is one of the few bosses who is particularly vulnerable to it at all points; while the Unformed is slightly more resistant to it, it can be rendered ineffectual too. Having strong buffed Stuns from the Plague Doctor, Occultist, or Crusader is particularly effective (Blasphemous Vial for the first and Demon's Cauldron for the second are invaluable here)
- because of the enforced lower Torchlight, the Horror can hit pretty hard throughout the fight, so while its offense is AOE-oriented, Maw of the Abyss (MotA) alone will force you to focus on self-healing skills and single-target healers, especially given that it will get multiple chances for round to get those darkness-buffed hits in. Occultist is recommended, but Vestal can be used if Divine Grace is fully upgraded. Because of how much DoT is being thrown around, Cure skills are mandatory if you have them available (Battleflield Medicine and Adrenaline Rush). This is why you stock up on Antivenoms & Bandages for this quest!
- you will want to focus on minimizing Stress over keeping everyone healthy if Camping beforehand; this fight is not as explicitly Stress-oriented as the rest of the Cove is, but it becomes such due to the increased crit chance in lower Torchlight, the lower Torchlight period, and the sheer force of Unearthly Knowledge's (UK) Horror. It doesn't help matters that he gets chances to spam UK (though he does not seem to have any predilection for doing so). It will be difficult if not impossible to prevent at least one Stress check from occurring, so if you are put any thought into Stress management outside of purely lowering it beforehand, focus on increasing Virtue Chance or any buffs gained from Afflictions instead of -%Stress or Stress healing--the Horror simply won't give you the breathing room to put much stock into the latter two
- Armor Piercing, +DMG, and +CRIT are the keys to victory here; much like with the Viscount, this is a burst-damage race where Marking won't be useful and where taking down the healing support first is a preferred option; but, unlike with the Viscount's Bloodbags, taking down the Unformed once it is summoned is mandatory due to how much it can drag along an already tough battle. This is a strange case of an enemy "party" where bursting down the Guard first is the way to go, as even with the buffs from Prayer of Protection (PoP), it lacks the raw stats and SPD to last more than a round or two if you packed enough damage to chop it down. Offensive-minded Crusaders and Shieldbreakers are best here, but Houndmasters, Hellions, and Highwaymen can work too, and the aforementioned Stuns PD and OCC provide can give you more time to smash it before it even sets those buffs down
- the previous point creates a sort of snowball effect: while the Horror will be beating on you hard during your Unformed-smashing, after those one or two rounds you can go back to damaging and stacking Blights on it, and because of the Return to Flesh (RtF) cooldown, the Horror will be forced to engage in the burst-damage race with you; because of its low SPD, as long as your healer keeps healing that same AP/+DMG/+CRIT focus will outpace its own DMG output, and force it to waste an action using Consume the Flesh (CtF) which it appears to prioritize once it's down below half-HP. While the self-heal can be demoralizing, keep in mind that it is an infinitely better situation to be facing than RtF; this reduces the number of Unformed you'll have to deal with
- much like with the Shambler, you must be ready to shuffle your party out of order before entering the Horror's room, as the guaranteed surprise threatens to waste the valuable first round getting your party back into place; a Shuffle-resistant team is good though not essential here, in case that surprise throws you for a loop no matter what. While my 1st Horror kill was done with (mostly) a modded-class team, my 2nd kill was done with no deaths, and with such a party of PD/OCC/HWM/Shieldbreaker (everyone except the Doctor can either move themselves or can function in virtually any position). This surprise factor is what eliminates the Arbalest or Leper from consideration for this battle; Crusader, Hellion, and Man-at-Arms are alternative choices. Houndmaster is shuffle-resistant but but his specific toolkit is a bit slow for this specific battle unless you're orienting him towards Blackjack duty
- Shieldbreaker deserves special mention here for her toolkit being exceedingly good in this battle: Snake Eyes for helping everyone else cut through the opposition's PROT; Pierce as a whole (Puncture is available but not optimal since you want to be focusing on the Unformed when both foes are out on the field) Blight-oriented offense for the Horror and in particular, the sheer output of Adder's Kiss. Serpent Sway can also help save her when the Horror's offense starts to grind her down

After the Battle

When you have downed the Lumberjack, he automatically drops one of his two Trophies; which he drops is random:

https://steamcommunity.com/sharedfiles/filedetails/?id=1939787443

Bear in mind that the quest isn't over yet: if you came from the northwest, you'll still have to travel east and downward to clear the one Room Battle near the Prisoner Room, along with the hallway on your way there; if you came from the northwest, you'll still have to head west and clear the one Room Battle; after this battle, these remaining combats should be cake unless you lost a party member fighting the Horror. Remember that any Camping buffs you put on before the boss will easily last you the remainder of the quest.

When you finally beat the quest, as noted in the mod description, you then have a low chance of running into the Horror again during any Champion Cove quest, which gives you the chance to beat him again and net his other Trophy trinket; the same strategies as noted earlier apply. Much like his "brethren" the Lumberjack, you will know if he spawns in your chosen quest when he graces your dungeon loading screen. Unlike the Lumberjack--who always spawns in a hallway--the Horror will always spawn in a room, like he does for the quest.

A Few Thanks and Acknowledgements

- A Slightly Startled Seal for granting me permission to write my this guide: https://steamcommunity.com/id/slightlystartled/
His playlist of mods, if you find this one to be fun: https://steamcommunity.com/workshop/filedetails/?id=1358805026
- Dismas for helping with the art for this mod: though we haven't spoken yet, I hope he's also happy that someone took this much interest in some of his work: https://steamcommunity.com/id/dismas_reynauld/
- the ElementFive's Hive Discord, for sucking me into the wackiness of the DD modded world ever deeper, and being a whole buncha weirdos who this weirdo can mingle with: https://discordapp.com/channels/363567210599546880/520344246176448512

[Nmrr]

Well since my party was made on that rank supposed 3 attack, that's was a damn luck O_o
Thanks for answering btw :) and gl to find if it was a bug or just me !

[Smuckem]

@Nmrr I don't believe so, last time I fought him he attacked those Ranks as normal....since Maw has no targeting biases, at least any that I'm aware of, it just can roll the same party member a bunch. With that said, I should ask Seal if he embedded any targeting biases into any of his offense as a formality...

[Nmrr]

hi, asking a thing, i fighted that boss and he only attack my rank 3 with the "Maw of the Abyss" thing, it is a bug ? cause the guid is telling that it can use it on ranks 1, 2 and 3
It made me the boss really easier cause i only had to put high prot on rank 3

[Smuckem]

Yeah sure!

[Seal]

Heya, the guide looks good! Is it ok if I put it on the mod page like the Lumberjack's Guide?