Tonnes of Health and Thorns! (200K Health and 3M Thorns!!!)

Become Invincible as the Templar
Walk into enemies and watch the masses get electrocuted
Make your computer lag **I MEAN** look beautiful with the sheer number of lightning orbs that will brighten up your screen
Acquire 200,000 Health and 3,000,000 Thorns with ease

Intro

Hello person! In this guide I will tell you how you can get enormous amounts of health, and with this abundance of health, thorns.

UPDATE:
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Unfortunately, halfway through making this guide a few years back, there were a few things that changed to thorns that kinda made this not viable, but with the item sets now having some interactions with thorns, I thought I'd have a shot at making a thorns build that is viable. I'm still abusing the "Retaliator" set bonus, and with the new transmute person I can upgrade the base stats to those of True Legendary calibur (Huzzah!). The elementium-heartstone combo is also still heavily at use here, giving us a tonne of health to increase our thorns, and to sort of bolster our effective HP in higher Anomalies.

There are two ways to go about this build now - Using the Tome of Wrath, the "Reckoning" helmet and mainhand to have an on-hit thorns build, or to have 3 pieces (the helmet, offhand and mainhand) of the "Thundercharged" kit, allowing for better optimized enchantments.

If you continue to read ahead and do this, just bear in mind that this guide still needs fully updating. I'll get around to it properly at some stage. Until then, you do you :)
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This build is about clearing hordes of enemies more than anything else. Against bosses it works okay-ish, and flurrying opponents are your friends that you want to hug the most. I reckon in Co-op this build would be good if your friend played a character that dealt lots of single target damage to clear tougher enemies.

The helmet and weapon are changeable, but everything else is core. I believe this to be an optimized item choice, however, as without the Life-Guard you will take almost twice as much damage, making you prone to being bursted in higher anomaly levels.

The heartstone-elementium armour combo can be utilised in companion builds too, as with "The Unbreakable Bond" companions will take 80% less damage, more than making up for the loss in resistances. Note that this isn't advisable to use with short-lived companions like the wisps from the warden's tree, as they don't need much health; They deal damage and by the time they are about to die without this combination I imagine they would sooner expire due to effect duration.

Items that have been utilized are:

Ability and Mastery Trees

For masteries, maximise Thundering Wrath while making sure to pick up Precision Strikes and all 3 Enhanced Resistances


Holy tree for the ultimate shield and 15% CDR aura. Divine Intervention is OP because it heals you to full health then adds 350% of your maximum health as a shield that won't get popped for the next 25 seconds. On less than a 10 second cooldown (yes, less than. I'll get to that in a moment)
Devotion is also nice as it provides us with 20% more thorns from just Reprisal, the thorns aura.
Grace is additional cockblock as when it triggers it increases maximum health (and therefore increases thorns too) and generates a shield that gets damaged before the ultimate shield can be damaged. Having a tome makes it a 15% chance to trigger also, so OP OP, right?

Fire tree should be 100% empty. Not a single point in here. Not worth it.

Lightning tree has the Lightning Thorns and Avenger passive abilities that are REQUIRED for this build. Attack speed helps cast speed a tiny amount, and critical chance is very useful. Surge is the ability that should be taken, as it lasts a while, makes lots of orbs (that with the ricochet passive) bounce off of walls and helps sustain mana so that you can dash around and cast this ability more. Each cast of this ability, with 2 points in the Reloaded passive, reduces the remaining cooldowns of abilities by 9%

Ahh, yes. The physical tree. This tree is where most of your health is derived from, as it has most of the passives that grant resistances (which provide health instead because of the heartstone!)
It also is home to the thorns aura, Reprisal, and the most useful dash ability. I have picked "Charge" simply because it helps group enemies if you get the knack of how it works. You can push enemies that stretch out into lines into a cluster, which then makes them all in range for you to make them electrocute themselves on your cattleprod... ... ... lightning rod? ... I give up xD

How The Build Works: Elementium - Heartstone Combo

This build works because of a synergy between the Heartstone, Elementium armour and having 3 parts of the Retaliators set.

The Heartstone increases health by 50% of your total resistances, and Elementium armor increases all of your other resistances by 50% of the highest resistance you have. This results in an enormous amount of health alone, and is further increased by resistance enchantments. Furthermore, even though your resistances are nullified, your effective health against any form of damage is increased drastically. This is because you essentially have all of your other resistances being useful against every kind of damage due to the conversion to health. Negative resistances from entering harder difficulties cannot reduce your maximum health, but enemies do just a tiny bit more for each % it goes into the negatives. Not that it matters a whole lot with an ultimate ability you will want to pick up ;)

How to maximize Elementium Armour's efficiency:
Due to the nature of how Elementium Armour works, stacking only one kind of resistance is most beneficial, as half of the highest resistance stat is added to the 6 other resistances (as there are 7 resistances in total: Physical, Holy, Shadow, Fire, Ice, Lightning, Poison). Physical resistance is less ideal to stack due to the enchantment taking a major slot unlike all the other resistances taking minor slots. Knowing this, just pick one type of resistance and stick with it - in my build I picked shadow (because why not?).
Resistances List:
Masteries - 30% to all
Shield Dance - 25% Physical, 10% Non-Physical (Or 10% to all and another +15% to physical)
Items - 75% to all, 100% Shadow, 20% Frost
Fortress - 12% Physical
Enchanted Armor - 12% Non-Physical
(Both fortress and enchanted armor combine to make 12% to all)
Forbearance - 10% to all
Total: 137% to all, +15% Physical, +100% Shadow, +20% Frost (Shield dance numbers have been shuffled for convenience, just trust my numbers if you don't understand what I did to get these numbers)
Total with half of total shadow resistance (237% divided by 2 = 118.5%) added to other resistances: 237% Shadow, 255.5% Fire, Poison, Lightning, Holy, 270.5% Physical, 275.5% Frost = 1805% Combined.
Half of 1805% is converted into % boost to maximum health = 902.5% boost

Thus, health is effectively multiplied by 9.025x
But wait - There's more!

Having points in the physical tree increases maximum health by a small %, and the tank passive gives 20% max health rank 5. With my build, I have 34 points in the physical tree, granting approximately 3% max health (possibly 3.4% if it is hiding the decimals)
With a ~23% boost to maximum health, health is effectively multiplied by 11.10075x
(Math check, using 10 as a substitute number representing health:
10 * 9.025 * 1.23 = 111.0075
Every 10 points of health gets increased to 111.0075 health!)

How the Build Works: Thorns Calculations

As briefly mentioned in the previous section, 3 pieces in the "Retaliators" set grants 50% of your damage stat in additional thorns, and 30% of your maximum health in additional thorns also.

So, you should end up with approximately 200,000 to 280,000 maximum health with this build and around 5,000 damage. The set bonus should provide at least 62,500 (60,000 + 2,500) to 86,500 (84,000 + 2,500) thorns. These thorns, plus extra thorns from items and passive skills (which should total around 15,000), get increased by the elemental bonus (which for this build will be lightning damage), 6 * 20% bonus thorns from gems (120% increase), and increased by the mastery "Thundering Wrath". By having the Tome of Wrath also, Avenger deals 100% additional damage (which effectively doubles EVERYTHING, as it increases total damage by 100%), and because of the Avenger passive, thorns is dealt as chain lightning and consequently destroys swarms of enemies who clump up and all attack you at once. Furthermore, thorns can critically strike, so critical damage is insane - the Tome of Wrath's avenger bonus basically makes it so that the critical damage stat is doubled!

Unfortunately, a bug I discovered with the aura "Reprisal" is that it doesn't increase thorns from set bonuses. It still increases the other thorns by 25%, but its effect pretty much only raises thorns by about 100,000 in the grand scheme of things, instead of ~800k-900k ;/
Sad times are these...
Squarebit is aware of this bug, and probably looked at my block of maths in the bug report and thought "Holy balls! A nerd just calculated every part of thorns to prove that reprisal is broken!"
While it isn't on his list of things he is currently working on fixing, he will get around to it eventually... (...I hope)

The bug report for quick reference of those who are curious...

The Templar's physical tree thorns aura, "Reprisal", does not seem to increase total thorns by the specified 25%. It doesn't interact with additional thorns from sources like the retaliators set.
Maths based on my stats when equipping 3 parts of the retaliator's set and elementium armor with 3 +20% thorns gems, and an additional 1 on boots for 4 in total for an 80% boost to thorns:
18,188 Health * 30% = 5456.4
1611 Damage * 50% = 805.5
Templar Reprisal Aura Tooltip = 4537.5
Thorns from base item stats = 2 * 1800 = 3600
Thorns from masteries and skill trees (miscellaneous extras) = 600 (Retribution passive) + 217 (Physical tree bonus from 34 points in the tree) + 30 (one mastery point in Thorned Shield) = 847
Total base thorns = sum of the above = 15246.4
Gems bonus = + 80%
Elemental bonus (Lightning as I have the passive "Lightning Thorns") = 411%
Total thorns with % bonuses = 112,792.8672
(Its at this point where I looked back on my maths and double checked - for some reason the calculation in game makes it 112,724? There might be hidden decimals some places that got rounded up...)

Not only that, but when using Reprisal's active for 25% of total thorns bonus, I expect to get 1.25 * 112,724 (I'll use the number stated in-game) = 140,905. Instead I get 128,380.

Going back, if the set bonus thorns is removed for the 25% increase alone...
15246.4 - (5456.4 + 805.5) = 8984.5
Thorns without set bonus thorns with % bonuses = 66467.331
Increase " -- " -- " by 25% = 66467.331 * 1.25 = 83084.16375
Calculate the set bonus thorns as standalone = (5456.4 + 805.5) * 1.8 * 4.11 = 46325.5362
Add the Increased "Thorns without set bonus thorns with % bonuses" to the standalone set bonus and you get 83084.16375 + 46325.5362 = 129,409.69995

Hmmm... assuming that there are some decimals that are hidden in tooltips (the thorns from the physical tree bonus is a likely culprit) it seems close enough to the 128,380, which is less than 1% error. Hopefully you can look into item sets interaction with this calculation, as it feels like I'm being cheated damage that I expect to get from having a set bonus.

You may want to go and double check the maths for yourself, but I'm sure I've done it as accurately as I possibly could have with the numbers I have availble to view in detail and left sufficient workings and described where numbers have come from and how they have been operated

EDIT: Just wanted to add that although the set item does specify "Adds x% thorns from damage and health", key word being Add, when the tooltip of reprisal states that Total thorns is increased by 25% I would hope that it would actually do the total amount. I would assume that from the wording alone that the calculation in the script simply has the set bonus added on the outside, looking something like this:
Thorns = ((Base Thorns * Thorns%Bonus * Elemental%Bonus * Other%BoostsFromStats) + "SetBonus" ((Damage*0.5 + Health*0.3) * Thorns%Bonus * Elemental%Bonus)

Upcoming Changes to This Build

I was thinking of changing the stat choices on some items, but haven't found items that exceed the base stats of the stuff I have right now to re-enchant.
>Elementium Armour's Power All to become Health
>Rolling Thunder's Major Enchants to become Crit Damage and Health
>Choker's Power All to become Crit Chance
>Tome's Major Enchants to become Crit Chance and Crit Damage

I would be left with 78% Crit Chance (which is acceptable) and (with 10 points in the "Precise Strikes" Mastery for an additional 20% critical damage) 240% Critical Damage. Throw Tome of Wrath's "Avenger" passive in and damage is doubled, so crits do 480% instead. Yeah, 25% Crit damage basically becomes 50% Crit damage.

And yes... Thorns CAN crit
... I found out after I had already enchanted all of my gear ;(

EDIT 09/06/17:
Fixed some formatting issues with images converging with text that I didn't notice. The preview lied to me!
Also, I changed what skills I was using for this build and came up with something that deals more damage overall. Not as much health, as Shield dance is no longer used, but I'm now utilizing 2 abilities that apply debuffs to enemies causing them to take more damage. I'll update the guide to reflect the ability changes I've made.

EDIT 18/08/19:
Saw that people are actually still coming across this, I ought to actually update this lmao. This stuff is ancient!
When I can acquire enough crowns and glyphs/tablets (or whatever it is that they're called again, haven't kept my eyes on this game in a long while) I'll reinvent the build from the ground up. Last I remember this build got hit pretty hard by reprisal becoming additive, making it scale less. That, and some mastery stuff got reworked meaning thorns from those were limited further. I'll also be investigating the new mastery and skill trees to see what I can wring out.

EDIT 25/08/19:
I HAVE MORE POWER NOW! MWAHAHAH!
Ahem! Excuse my manic moment there. This build is coming soon with 500K+ Max HP, 30M+ Thorns, and a ton more interactivity than the previous build. Might I just add that Lusombra's is pretty nice, definitely not broken or anything. Chilling with my 2500% Holy Damage, casually, haven't even max'd out the enchantment. Pls no nerf square. I beg.

[TheOneTrueWeasel]

@lockmasterkal thanks ill look into that. Ive been messing around with different setups but quite have all the gear together yet so i guess i get to farm for a while longer before i can actually get it going 100%.

[LockmasterKal]

@TheOneTrueWeasel Very much so! There are a few approaches that I have found, though I've delved down the holy route mostly. Lightning and physical thorns builds look like they want to utilise satellites and on-hit, if that helps you brainstorm your own build.

[TheOneTrueWeasel]

I wonder is a build like this still viable? im looking into making a thorns build and i think this would be a good starting point.

[Rayonaie]

does thorns trigger static overload if you have lightning thorns ?

[LockmasterKal]

Unfortunately, yes, its now capped. This build got hit by a nerf bat pretty hard!
I'll rejig the guide to match the updates (eventually), as this probably isn't as viable without some other primary focus.
RIP millions of thorns, my 4M got cut to 2M in a fell swoop ;_;

[吳爾羅]

now the thundering wrath has the maxium rank.