[3.20] Enki's Arc Witch - a beginner-friendly Caster

Main Skill

Arc - Your main damage skill. It chains between enemies (up to a limit) and releases a secondary chain to a nearby enemy each time it chains. If the chain limit is not reached, the skill receives 15% more damage for each remaining chain to improve its single target capability.

E.g. if 7 chains remain, the skill receives a 105% (7*15%) more damage multiplier.

The support gems used for this skill to enhance its damage are Spell Echo, Lightning Penetration, Inspiration, Arcane Surge & Added Lightning Damage in that order, socketed in your body armour.

Warning: Arcane Surge needs to stay at Level 15! This lets you gain its buff within 4 casts for consistent uptime, without giving up too much of its effect.


Secondary Skill

Galvanic Field - Additional damage skill for tanky enemies. Casting it grants a buff that places a field onto an enemy when you shock them. It gets enhanced based on the shock debuff value and periodically damages enemies within its AoE for a duration. Only one field can exist at a time.

The support gems used for this skill to enhance its damage are Elemental Focus, Added Lightning Damage, Lightning Penetration, Inspiration & Cruelty in that order. A staff is required to upgrade it past four links, until then it doesn't matter where you socket it.


Movement Skill

Flame Dash - Lets you instantly travel some distance to get out of danger or simply just move. Any damage source on the travel route gets ignored. Each use costs a charge, of which it can store up to three that get replenished after a cooldown. Socket it wherever you can.


Debuff

Wave of Conviction - Debuffs the enemy with exposure of the highest elemental damage it deals.

Warning: Keep this gem at a low level to protect yourself from physical reflect!


Golem Buffs

Lightning, Stone, Ice, Chaos - These minions are only used for the buffs they grant you, which get further enhanced by passives and your ascendancy. The latter also grants them immunity to elemental damage and resummons them shortly after they die. It doesn't matter where you socket them, neither do they have to be linked together.


Auras

Clarity, Wrath, Determination - These auras reserve some of your mana to grant buffs. Just like the previous gems, it doesn't matter where you socket them and they don't have to be linked.


Trigger Setup

Molten Shell, Enfeeble - Both skills are linked to Cast when Damage Taken to automate them. They get triggered upon accumulating enough damage taken from hits. This threshold depends on CwDT's gem level, which also decides the maximum level the triggered spells can have.

To make this work properly, you need to keep:

‣ Cast when Damage Taken at Level 10
‣ Molten Shell at Level 15
‣ Enfeeble at Level 13

This assures a good balance between trigger rate and effectiveness.

Molten Shell soaks up a portion of incoming hit damage for its duration. The size of its damage buffer depends on your armour. For additional survivability you can use Vaal Molten Shell instead. This grants the regular skill alongside its buffed up Vaal version, which can be used on demand.

Enfeeble on the other hand is a curse that debuffs enemies by lowering their damage.

Before you do any content, make sure that your auras are activated, golems are spawned and that Arc and Flame Dash have "Always Attack without Moving" enabled.

For clearing, all you need is Arc. It has enough damage and coverage to deal with larger packs of monsters and ideally only takes one cast to clear them. Try to keep your Diamond, Granite and Quartz Flask up during that, their charges refill upon killing monsters.


For bosses and tanky enemies (e.g. Essence monsters) use the following rotation:

‣ cast Galvanic Field to gain the buff
‣ debuff the enemy with Wave of Conviction (if still used)
‣ recast Galvanic Field
‣ burst them down with Arc until the previous skills run out of duration

Repeat this rotation while circling the enemy until they're dead.


In both situations, use your Flame Dash or Quicksilver Flask to move between enemies or away from danger. If you have Vaal Molten Shell, activate your Granite Flask before using it to gain a larger damage buffer for risky situations.

This build primarily deals lightning spell damage inflicting the shock ailment. The damage gets further enhanced through the "Lightning Damage with Non-Critical Strikes is Lucky" mastery and Elemental Overload keystone, both endorsing minimum investment into critical strikes.


Focus on these modifiers to scale your damage:

‣ #% increased Lightning / Elemental / Spell Damage
‣ Minions deal #% increased Damage
‣ #% increased Cast Speed (too much causes mana issues)
‣ % increased Effect of Lightning / Non-Damaging Ailments
‣ Adds # to # Lightning Damage to Spells
‣ +1 to Level of all Lightning Skill Gems
‣ Wrath has #% increased Aura Effect
‣ #% increased Effect of Buffs granted by your Golems


These modifiers won't affect your damage:

‣ #% increased Elemental Damage with Attack Skills
‣ Minions deal # to # additional Lightning Damage
‣ Adds # to # Lightning Damage to Attacks
‣ Adds # to # Lightning Damage (only on Weapons)
‣ #% increased Attack Speed

This build uses life and armour as its base defenses. Additional survivability is gained through life regeneration and physical damage reduction, mostly coming from your golem buffs, and the Primal Aegis gained from Bastion of Elements along with reflected damage immunity. In endgame, the build also aims to get immunity to elemental ailments.


Focus on these modifiers to scale your survivability:

‣ +# to maximum Life
‣ #% increased maximum Life
‣ #% increased Armour
‣ #% additional Physical Damage Reduction
‣ #% of Physical Damage from Hits taken as Fire / Cold / Lightning Damage
‣ +#% to all maximum Resistances
‣ #% chance to avoid Elemental Ailments (needs to be 100% total)
‣ #% chance to avoid being Stunned (needs to be 100% total)
‣ You take #% reduced Extra Damage from Critical Strikes
‣ #% increased Effect of Buffs granted by your Golems

This is just short summary of build specific choices during the campaign.
If you need more help, check out my full Campaign Walkthrough.


Act 1

‣ Buy Spark from Nessa and link it with Arcane Surge.
‣ Get a second wand and look out for boots with Movement Speed.
‣ Get Quicksilver Flask as Mercy Mission reward.
‣ Get Frostblink and Orb of Storms as Breaking Some Eggs reward.
‣ After entering the Prison, get Added Lightning Damage from Nessa and link it to Spark.
‣ At Level 8, craft two wands by selling the following items to a vendor:

Magic-rarity Wand + Normal-rarity Topaz Ring + Orb of Alteration

‣ Topaz Rings can be made by selling an Iron Ring + Dexterity skill gem to a vendor.
‣ Look out for a Heavy Belt and Jade Amulet for Strength & Dexterity requirements.
‣ Get Flame Dash (replaces Frostblink) and Clarity as the Caged Brute reward.
‣ Get Arc (replaces Spark) after entering the Cavern of Wrath.

Passive Tree Goal


Act 2

‣ Get another Quicksilver Flask as the Great White Beast reward.
‣ Get Galvanic Field (replaces Orb of Storms), Wave of Conviction and Herald of Thunder after Intruders in Black.
‣ Get Elemental Focus as Sharp and Cruel reward and link it to Galvanic Field.
‣ Kill Kraityn, Alira and Oak to get two Passive Skill Points from Eramir.
‣ At Level 20, upgrade your wands with this vendor recipe:

Magic-rarity Wand + Rare-rarity Topaz Ring + Orb of Alteration

Passive Tree Goal


Act 3

‣ Start looking out for 4L gear during this act.
‣ Also work on getting your Fire, Cold and Lightning Resistance to 75%.
‣ Your crafting bench can help with that.
‣ Get Wrath and Enfeeble after Lost in Love.
‣ You need the mana mastery at Deep Thoughts to have enough mana to run Wrath.
‣ After A Fixture of Fate, get Inspiration and 2x Lightning Penetration
‣ Change your links as follows

Arc + Arcane Surge + Lightning Penetration + Inspiration
Galvanic Field + Elemental Focus + Added Lightning Damage + Lightning Penetration

Passive Tree Goal


Act 4

‣ Add Cast Speed to both of your wands after unlocking the recipe in Dried Lake.
‣ Finish the Labyrinth, ascend to Elementalist and get Liege of the Primordial.
‣ Together with the Golem Commander notable, you can now run three golems.
‣ Get Lightning, Stone and Ice Golem after Breaking the Seal.
‣ Get Spell Echo and Cast when Damage Taken after opening the Belly of the Beast.
‣ Replace Arcane Surge with Spell Echo in your Arc setup
‣ Get Molten Shell from Siosa in Act 3 and link it with Enfeeble and Cast when Damage Taken.
‣ Please keep their target levels in mind, they're listed in Skill Breakdown!

Passive Tree Goal


Act 5

‣ Get Granite Flask as the Key to Freedom reward.
‣ Use the Menagerie to add the following modifiers to your flasks:

Quicksilver Flask #1 - "of the Lizard"
Quicksilver Flask #2 - "of the Deer"
Granite Flask - "of the Conger"

‣ If it won't work, use Orbs of Alteration until the flask has no suffix modifier.
‣ After getting Sovereignty, get Determination and throw out Herald of Thunder.

Passive Tree Goal


Act 6

‣ Try to get your Fire, Cold and Lightning Resistance back to 75%.
‣ Activate the Soul of Ryslatha pantheon power after defeating Ryslatha.
‣ Activate the Soul of the Brine King pantheon power after defeating the Brine King.

Passive Tree Goal


Act 7

‣ Get Diamond Flask as the Silver Locket reward.
‣ Use the menagerie to craft "of the Urchin" onto your Diamond Flask.
‣ Finish the second Labyrinth and get Elemancer. You can now run four golems.
‣ Get Chaos Golem from Petarus and Vanja in Act 4.

Passive Tree Goal


Act 8

‣ Start looking out for wand upgrades. Use the Damage Scaling section as direction.
‣ If you have any Essences of Torment or Woe, you may hit an upgrade with those.

Passive Tree Goal


Act 9

‣ Nothing of importance to say here.

Passive Tree Goal


Act 10

‣ Get Quartz Flask as Safe Passage reward.
‣ Use the menagerie to craft "of the Skunk" onto your Quartz Flask.
‣ This replaced your Quicksilver Flask with "of the Lizard".
‣ Finish the third Labyrinth and get Bastion of Elements.

Passive Tree Goal

Here's your Passive Tree goal for this stage - It comes with a change to some early passives, which have lost their efficacy by now. To pull this off, put three points into the +10 Intelligence passives first, then remove the outdated passives.

Other than that, you'll pick up the last few life passives and Spiritual Aid within this step. This notable applies all "Minions deal #% increased Damage" modifiers to your damage, which opens up additional damage scaling options.

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Coming right out of the campaign, you likely don't have much currency to spend yet. That's why the focus at this stage is on budget gear that covers just the necessities to get you through the early part of the atlas.


Step 1: Basic Gear

Content gets a little harder now and you've just received another resistance penalty, so it's a good idea to bring up your gear to a new standard. This helps you survive maps and farm currency for future upgrades more efficiently.

Each piece needs to have 50+ Life (30+ for rings & amulet) and some Fire, Cold or Lightning Resistance. The distribution of those resistances doesn't matter, you just need enough to cap each at 75% in your character sheet. Additionally, your boots need 20%+ Movement Speed.

Sockets can be ignored while looking for these upgrades, it's easier to modify them to your needs than getting the right composition of stats on an item. Just make sure that the item isn't corrupted and has either Armour or Energy Shield, or even both. Avoid Evasion gear!

The crafting bench is still a good tool to add some of these modifiers to your gear, and continues to be for the entirety of your gearing process. Use it together with knowledge about the basic rules of crafting to your advantage while planning out your gear upgrades.


Step 2: Instant Life Flask

An instant life flask is an important tool to survive and shouldn't be neglected!

Luckily it's not that difficult to craft. Farm any Level 60+ zone until you get a Divine Life Flask drop, ideally with some quality on it. This is the best flask base for instant healing.

Use an Orb of Scouring on it (if it's magic rarity), get it to 20% quality with Glassblower's Baubles and then get it back to magic rarity with an Orb of Transmutation. Now use Orbs of Alteration until you hit Instant Recovery when on Low Life, then add of Sealing with the Menagerie.

This results in a "panic button" flask that will instantly heal most of your life if used while you dropped below 50% life, and additionally grants immunity to Bleed and Corrupted Blood.

Your flask setup should now be a Divine Life, Diamond, Quartz, Granite and Quicksilver Flask.


Step 3: Weapon

Now it's time to work on your damage. Agnerod West is an excellent staff for that purpose and usually cheap to get. Don't worry about its links for now, having a 4L is enough.


Step 4: 5L Body Armour

To further enhance your damage, get a body armour with five links to socket your Arc setup in. It's important that it's either Energy Shield or Armour + Energy Shield based, otherwise it'll be too difficult to get the colours you need.

If it lacks life, use the crafting bench or an Essence of Greed to craft it.


Step 5: Vaal Molten Shell

If you haven't found a Vaal Molten Shell gem yet, buy one now to be prepared for harder content. This replaces your regular Molten Shell gem.

Here's your Passive Tree goal for this stage - You'll pick up the last few masteries, then start investing into jewel sockets. Your final ascendancy passives grant a huge buff to exposure.

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This is just an intermediate stage. While breaking into red tier maps doesn't require much, it still helps to invest a bit into your character to have a smoother progression towards endgame.

Damage can feel a bit lacking now but keep going! This will be fixed within the endgame stage.


Step 1: Gear Upgrades

Now is a good time to gain more life. Aim for 70+ Life on your helmet, gloves, boots and belt (40+ on rings), once again with enough Fire, Cold and Lightning Resistance to cap them at 75% and on Armour + Energy Shield bases. Some Chaos Resistance also helps if you can fit it within your budget. These pieces shouldn't cost you more than a few Chaos Orbs each.


Step 2: Jewels

You start investing into jewel sockets within this stage, so it's a no brainer that you'll also need some jewels to socket. These are basically customizable notables with a wide variety of stats.
The focus for now is just on two damage stats each, to keep your investment low.

Here's a trade search with all relevant modifiers, listing them here would simply be too much. Make sure to change it to your current league before you buy anything!


Step 3: +1 Level Amulet

A great way to scale the damage of any spell is raising their gem level. One of the most accessible sources for this is the amulet slot.

The according modifiers for this are +1 to Level of all Lightning Skill Gems and +1 to Level of all Skill Gems, get one of them together with 40+ Life and either Spell Damage, Lightning Damage or Cast Speed. If it has an open suffix, you can also add #% increased Effect of Non-Damaging Ailments with the crafting bench to enhance your shocks.

Ideally you get this on an Onyx, Turquoise, Citrine or Jade Amulet for Dexterity requirements. Otherwise you have to get some Dexterity on one of your jewels.

While this can be costly, a good amulet will last you into endgame and is worth the investment.


Step 4: 6L Body Armour

A 6L body armour allows you to use the full Arc gem setup to gain another major damage boost.

The best base is a Saint's Hauberk, however any Armour + Energy Shield base that isn't unique or corrupted works. You'll craft this later, just use some Essences now to get 80+ Life.


Step 5: 5L Agnerod West

This step is optional, as you'll upgrade to a different weapon in endgame.

If you don't mind and can find one for cheap, getting a 5L Agnerod West allows you to add another support gem to your Galvanic Field setup to gain another damage boost.

Here's your Passive Tree goal for this stage - The base passive tree is done, now you'll get to expand into a cluster jewel to finalize your build.

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This is where the build really starts to shine! While the previous stages kept investment low enough to let you progress and accumulate more currency, it's time to invest that to gain a massive spike in build power and make your character ready for endgame encounters.


Step 1: Cluster Jewel

Cluster jewels expand your passive tree and can only be socketed into large jewel sockets.

This build only uses a Large Cluster Jewel, which grants two jewel sockets alongside its passives. There are different options, go for Adds 8 Passive Skills regardless of which one you choose.

Minion Damage: Has the best notable with Primordial Bond, but nothing else. Still a good option if you get that together with Added Small Passive Skills have #% increased Effect.

Lightning Damage: Has many good notables such as Overshock, Thunderstruck and Doryani's Lesson, but getting a good one can be harder to craft.

Elemental Damage: Similar to the previous one, but with less choices. Can be good if you only want Doryani's Lesson to have some leech.

Each choice requires an item level of 68+ for the important notables.


Step 2: Level 21 Arc & Galvanic Field

While the limit for most gems is Level 20, it's possible to get them to Level 21 by using a Vaal Orb on an uncorrupted Level 20 gem. Try it out once your Arc and Galvanic Field hit Level 20!

If luck isn't on your side, you can usually buy them for fairly cheap. Quality isn't needed!


Step 3.1: The Annihilating Light

The endgame build revolves around the Annihilating Light staff. This weapon triples the damage of your Arc and Galvanic Field, but has an equally heavy downside: all Elemental Resistances that you invest in lose more than half of their value!

This requires a lot of additional investment to cap your resistances and makes the staff the central point of your gearing process, but it's just so insanely strong that it's worth it.

A 5L is good enough, just don't get anything higher than 62% reduced Elemental Resistances!
You can farm the Searing Exarch for another one to try and 6L it yourself in the meantime.

Add Grants 1% increased Elemental Damage per 2% Quality with your horticrafting station.

The following six steps are all tied to this upgrade and should ideally be done at the same time.


Step 3.2: Enchanted Helmet

Since it's unlikely to find a good helmet with the right enchantment, start with getting either 150% increased Effect of the Buff granted by your Lightning Golems or Arc Chains an additional time on an Armour base. At this point you should have enough currency to force the right colors with your crafting bench.

Now use Essences until you hit one of the following outcomes:

‣ 30%+ Fire, Cold & Lightning Resistance: Add Life with the crafting bench.
‣ 50+ Life + 2x 30%+ Resistances: Add the missing Resistance if possible.
‣ 50+ Life + 2x 30%+ Resistances: Add #% of Physical Damage from Hits taken as Fire Damage.


Step 3.3: Essence-crafted Boots

Start with Armour boots with 70+ Life fractured. Now use Deafening Essences of Loathing until you hit atleast 30%+ Resistance and 20%+ Movement Speed or an open prefix to add Movement Speed + Onslaught on Kill with the crafting bench.

This is your first step (heh) towards 100% chance to avoid Elemental Ailments.


Step 3.4: Crafting your Body Armour

Now it's time to properly craft your 6L body armour. The goal is 100+ Life, 6%+ Physical Damage Reduction and 30%+ Resistance together with an open prefix.

The easiest way is using Jagged and Pristine Fossils, you can also try your luck with Essences.

Once you've hit it, add #% chance to Avoid Elemental Ailments with the crafting bench and keep readding until it hits 25%. Now you should be at 56%+ total.


Step 3.5: Anointment (Amulet Upgrade optional)

Anointing your amulet with Crystal Skin adds another 20% to your Elemental Ailment avoidance, bringing you to 76%+ total, and raises your maximum Elemental Resistances.

The Oils needed for this are: 1x Silver Oil, 1x Black Oil, 1x Sepia Oil

If you couldn't afford or find a good amulet before, you should upgrade it first based on the recommendation in the Midgame stage.


Step 3.6: Gear Upgrades

Unequip everything but your staff, body armour, helmet, boots and amulet to help you planning out the remaining upgrades. Each piece should be Armour or Armour + Energy Shield based with 60+ Life (40+ on rings) and lots of Fire, Cold and Lightning Resistance.

The belt should be a Stygian Vise, this lets you socket an abyss jewel. Rings are ideally Amethyst Rings, unless you need other bases to cap your Elemental Resistances.

The Resistances on your belt and rings can be further enhanced with 20x Prismatic Catalysts each.

While looking for upgrades, remember that your crafting bench can add enough Life or up to 35% of each Resistance and that the Resistance values get reduced by your staff.

E.g. with 60% reduced Elemental Resistances, 40% Resistance turns into 16% (40*0.4).


Step 3.7: Eldritch Implicits

This is the final step to refine your newly acquired gear. Eldritch currency can be used to add a Searing Exarch and Eater of Worlds implicit, as long as the item doesn't have a different influence.

Highest priority is rolling #% chance to avoid Elemental Ailments on your boots, which is an Eater of Worlds implicit. If the Essence modifier on your boots is at 35%, using Greater Eldritch Ichors is enough, otherwise you need to use higher tier ichors or Orbs of Conflict to reach a total of 100% chance to avoid Elemental Ailments.

Next work on rolling Inflict Lightning Exposure on Hit on your gloves, another Eater of Worlds implicit. This automates your exposure application and lets you remove Wave of Conviction.

The remaining implicits are less important, finish them while moving to the next steps:

‣ +1% to all maximum Resistances (Body Armour, Searing Exarch)
‣ Wrath has #% increased Aura Effect (Body Armour, Eater of Worlds)
‣ Adds # to # Lightning Damage to Spells (Helmet, Searing Exarch)
‣ #% of Physical Damage from Hits taken as # (Helmet, Eater of Worlds)
‣ #% chance to Unnerve Enemies for 4 seconds on Hit (Gloves, Searing Exarch)
‣ #% increased Action Speed (Boots, Searing Exarch)


Step 4: Flask Upgrades

Now that you're immune to elemental ailments, you can get different suffixes on your flasks.

First you should get an item level 84+ base of each flask to be able to get higher tier modifiers. Bring them up to 20% quality, then craft your flasks as follows:

‣ Divine Life Flask: Instant Recovery when on Low Life + Bleeding / Corrupted Blood Immunity
‣ Diamond Flask: Increased Duration + Cast Speed
‣ Granite Flask: Increased Duration + Armour
‣ Quicksilver Flask: Increased Duration + Movement Speed

The last slot is flexible. You can continue using a Quartz Flask or use an Amethyst Flask for additional chaos resistance, in both cases go for Maximum Charges and Poison Immunity.

You can work on this step while already moving on to the next steps.


Step 5: Boot Enchantment

This step doesn't require you to buy anything, simply just farm the Eternal Labyrinth until you hit Adds 1 to 160 Lightning Damage if you haven't Killed Recently on your boots.


Step 6: Stun Immunity

The elemental ailment avoidance craft on your body armour also has Chance to avoid Stuns. Abyss jewels can help you to get this value to 100%, which makes you immune to stuns.
Try to reach this within three jewels.

Here's a trade link, if the choices are too expensive you can also go with cheaper options in exchange for some life or damage.


Step 7: Pantheon Upgrades

Being immune to stuns and elemental ailments, you don't need to use Soul of the Brine King any longer. Switch over to Soul of Arakaali for additional DoT mitigation and use Divine Vessels to get all of its upgrades. Soul of Ryslatha is still used and should also be upgraded.


Step 8: Alternate Quality Gems

There's a few alternate quality gems that are worth getting for this build:

‣ Anomalous Spell Echo
‣ Anomalous Summon Lightning Golem
‣ Anomalous Summon Stone Golem
‣ Anomalous Summon Ice Golem
‣ Anomalous Summon Flame Golem
‣ Anomalous Wrath

For Summon Chaos Golem, Level 21 is more important if you have +1 to Level of all Skill Gems on your amulet. This raises its Physical Damage Reduction buff to 5%.


Step 9: Unique Jewels

The first jewel that you should buy is an Anima Stone to be able to summon a fifth golem, Summon Flame Golem in this case.

Next is a Watcher's Eye with #% increased Lightning Damage while affected by Wrath or Damage Penetrates #% Lightning Resistance while affected by Wrath, ideally together with one of these modifiers:

‣ You take #% reduced Extra Damage from Critical Strikes while affected by Determination
‣ #% additional Physical Damage Reduction while affected by Determination


Step 10: 6L Annihilating Light

Getting a 6L Annihilating Light allows you to use the full Galvanic Field setup. Same as before, aim for a low reduced Elemental Resistances roll and use your horticrafting station to add Grants 1% increased Elemental Damage per 2% Quality.


Step 11: Awakened Gems

Awakened gems are stronger versions of their regular counterparts. They cap out at Level 5 and gain an additional effect upon reaching that point.

Get these awakened gems for Arc:

‣ Awakened Added Lightning Damage
‣ Awakened Lightning Penetration

Get these awakened gems for Galvanic Field:

‣ Awakened Elemental Focus
‣ Awakened Added Lightning Damage
‣ Awakened Lightning Penetration

This build can't run Players cannot Regenerate Life, Mana or Energy Shield.

Other mods that are notably bad are:

‣ Players cannot inflict Exposure
‣ Monsters have #% chance to Avoid Elemental Ailments
‣ Players have #% less Recovery Rate of Life and Energy Shield
‣ Monsters have +#% chance to Suppress Spell Damage

If you're running Searing Exarch or Eater of World influenced maps, I also recommend to avoid Monsters fire 2 additional Projectiles if you want to level up.

Atlas passives aren't tied to builds and are something that you plan and adjust based on the mechanics you want to engage with.

That said, I recommend to invest into all Essence atlas passives early on to build up a sizeable pool while completing your atlas. They'll be useful to craft some of your Endgame gear, such as your helmet, boots or belt, and the excess stock can be sold to afford other upgrades.

These are harder versions of endgame bossfights that can be unlocked through atlas passives.

While this build can do most of them with the endgame setup, I recommend a dedicated bosskiller build if you plan to farm them.

If you want to give it a try, here's the minimum stats I recommend to have:

‣ 1.5m+ DPS (POB, Arc + Galvanic Field combined, Uber Pinnacle Boss setting)
‣ 5k+ Life + 600+ Life Regeneration
‣ 77% Elemental Resistances
‣ 20%+ Physical Damage Reduction (buffed Chaos Golem + Watcher's Eye or Body Armour)
‣ Elemental Ailment Immunity
‣ Stun Immunity
‣ adjusted Flask Setup (see below)

It's also helpful to check out videos to familiarize yourself with their additional mechanics.

Now to the flask setups. Regardless of the fight, I recommend to have 2x Divine Life Flasks with Instant Recovery when on Low Life, the remaining flasks depend on the fight.

Shaper (Cosmic Wounds): Sapphire Flask + Granite Flask + Silver Flask
Uber Elder (Cosmic Wounds): Sapphire Flask + Granite Flask + Silver Flask
Maven (Throw the Gauntlet): Sapphire Flask + Topaz Flask + Quicksilver Flask
Cortex (Memento Mori): Ruby Flask + Sapphire Flask + Topaz Flask
Searing Exarch (Thirst for Knowledge): Ruby Flask + Granite Flask + Quicksilver Flask
Eater of Worlds (Insatiable Appetite): Topaz Flask + Granite Flask + Quicksilver Flask
Sirus (The Perfect Storm): Ruby Flask + Topaz Flask + Quicksilver Flask

I've beaten all but the Uber Pinnacle versions of the Eater of Worlds and Searing Exarch.
Let me know if you did them with this build!