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PoE 2 Build

[0.5.5] Cast on Block(Mana Flask) Reverse Chill Autobomber.

Updated on Oct 10, 2026
Oct 10, 2026

Build Overview

[WARNING!]

This Build is Actually Unplayable, because even though in theory it should be the 2nd best build in the entire POE2 history, to reach full potential you need to spam your mana flask continuously 10~20+ times per second and it's simply impossible for current human species

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This build uses the Melting Maelstrom Mana Flask to trigger Cast on Block.

The exact numbers will vary depending on your setup, but normally, your skills will trigger at least 10+ times per second with effectively infinite Mana.

By reducing Flask Charge consumption to an extreme degree, you can practically spam mana flask 20~30 times / sec and still not run out of charges, and it'll repeatedly keep triggering spells.

By combining a passive that grants increased Movement Speed based on the number of times you've Blocked in the past 10 seconds (Swift Blocking) +Reverse Chill(Sierran Inheritance), you can also reach around 400% Movement Speed.

With Gemling Legionnaire Additional Quality Effect of Cast on Dodge, your practical Movement Speed is estimated to be around 600%.

Life/Mana recovery is effectively infinite as well.

Damage, survivability, and mobility all come together perfectly in this build.

Unless you're comparing it to an absurdly high-budget Temporalis build with over 10 Mirrors invested into it, I honestly don't think there is currently another build that can outperform this one.

I would even say this may be the second best build in the entire history of POE2. (The #1 spot goes to prime Temporalis build from the first league.)

For your main skill, I recommend either Ice Nova or Spark.

However, this guide is written around Ice Nova. After considering both convenience and damage, I personally feel that Ice Nova is the better all-around option.

Spark deals less damage, but offers even better convenience.

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If I've missed anything or made a mistake, I know it may be a bit of a hassle, but please join my Discord server and let me know!

Link: http://discord.gg/3pwnbN5Af9

Strengths and Weaknesses

  • INSANE Mobility. If you don't play extreme high budget +10 mirror Temporalis builds, there's literally not even a single build in the game that can compare to this one.
  • High Max Hit, 80~90% Block Chance, And infinite Life/Mana Recovery. In most contents, it's literally harder to die than live. even if you wanna die intentionally, it's not easy. almost impossible when you're playing easier contents.
  • Very High Damage. With this setup I'm introducing today, around 30~40mil DPS.
  • Realistically, you can't actually play this build.
  • After you go inside the map, you'll need to wait 9 seconds first to trigger your skills.
  • Core Mechanic is Glitchy. Mana Flask/Cast On Block interaction is imo unintended. GGG Might want to nerf this mid-league

Build Variants

The estimated budget is around 1–3 Mirrors.

Viable With a Lot Cheaper Budget Too (Let's Say 2k divs) but I'm not sure if I will make a guide for cheaper version in future.

Btw, the setup I'm introducing today is focused on cost efficiency and minimizing reliance on very rare corrupted items so you don't need to overpay for stuffs.
If you'd like to see the exact setup I was personally using, please check the pobb down below!

pobb: https://pobb.in/Dh9Tdsb3gmZq

Spark version pobb: https://pobb.in/Z7rszMHTYoIE

Equipment

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Jewels
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Equipment Priority
+10

[MUST READ]

Skipping the detailed explanation and getting straight to the point: at 75% Chaos Resistance, your maximum Mana needs to be roughly 4 times your maximum Life for 50% maximum Reverse Chill.

You need to get at least one Attributes modifier in your suffix slot . (on Rings, or Gloves, or Boots.)

Make sure to get +50 Spirit on your Amulet.

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[WEAPON]

We use the unique weapon Runeseeker's Call

The best implicit is "+300 to maximum Runic Ward", but other implicits or even one without an implicit are perfectly fine.

For the Runes, use:

Hedgewitch Assandra's Rune of Wisdom (+1 to Level of all Spell Skills)

Aldur's Legacy: Legacy of Lifesprig (+2 to Level of all Spell Skills)

Warding Rune of Hollowing (Gain 15% of maximum Life as Extra maximum Runic Ward, 15% less maximum Life)

Perfect Iron Rune (35% increased Spell Damage)

Perfect Mind Rune x2 (+90 to maximum Mana)

A 5-socket version is also completely fine. If you're using a 5-socket version, remove one of the maximum Mana Runes.

[BODY ARMOUR]

Other options are absolutely viable too, but for the setup I'm introducing today, we use Sierran Inheritance for Reverse Chill.

This build already has more than enough damage and survivability, so I felt that using Reverse Chill to increase mobility was the best option overall.

A Runeforged version is better, but it's not a huge deal even if yours isn't Runeforged.

Socket one Fox Idol, then fill the remaining sockets with whatever Resistance or maximum Mana Runes you need.

Also Better to Have Mana Recoup Enchant Mod, But It's not Mandatory(Works well without it)

[HELMET]

Just like the Body Armour, there are plenty of other viable options for this slot, but the setup I'm introducing today is built around Alpha's Howl.

Runforged Version's better, and 0% quality is better. the lower the evasion is, the better it is.

But 20% quality is still absolutely fine, it's just a tiny bit of detail.

Buy an non-corrupted one, socket a Raven-Touched Shard into it, then anoint Swift Blocking.


[SHIELD]

We use Svalinn.

You MUST buy a corrupted one. (It needs to have the "10–15 Mana gained when you Block" corrupted modifier.)

It is completely fine if it has the modifier that causes you to take damage from Blocked Hits. The build still functions properly, and its survivability is still excellent.

Ideally, Cast on Block should be Level 20 with 5 sockets. However, if there aren't any available on the market, you'll unfortunately have to get the one without them.

Socket an Ox Idol to increase the base Block chance. (Mandatory)


[AMULET]

Use an Absent Amulet base with Cast on Dodge

Make sure to get 40% Caster Quality if possible.

-Prefixes (in order of priority)

1. +50 Spirit (Mandatory)

2. Maximum Mana

3. #% increased maximum Mana

-Suffixes (in order of priority)

1. +3 to Level of all Spell Skills

2. +5% to Quality of all Skills

anoint: Paragon (You can also put Paragon on your Helmet and instill Swift Blocking here instead. Either way is fine.)


[RINGS]

I highly recommend using a Mnemonic Ring base.

-Prefixes (in order of priority)

1. Maximum Mana

2. #% increased maximum Mana

3. #% increased Cold Damage or Item Rarity

-Suffixes (in order of priority)

1. All Elemental Resistances

2. Chaos Resistance

3. Attributes (Strength, Dexterity, Intelligence, or all Attributes are all fine)

4. Any other useful modifier


[GLOVES]

-Prefixes

Energy Shield and maximum Mana (ideally 2 Energy Shield prefixes and 1 maximum Mana prefix)

-Suffixes (in order of priority)

1. 60% increased effect of Socketed Augment Items

2. Get as much Resistance as you need. If your Resistances are already capped, use any other useful modifier instead. (Attributes are also useful.)

Make sure to socket one Tecrod's Gaze!


[BOOTS]

-Prefixes

Get Energy Shield, maximum Mana, and Movement Speed according to your preference. (You might wonder why you'd bother getting a measly 35% Movement Speed, but it makes a quite noticeable difference in QoL before the build gets fully ramped up.)

-Suffixes

Get as much Resistance as you need. If your Resistances are already capped, use any other useful modifier instead. (Attributes are also useful.)


[BELT]

This is EXTREMELY important.

You MUST use a Mail Belt base.

For the prefixes, I strongly recommend getting "#% chance for Flasks you use to not consume Charges", and for the suffixes, you MUST get "reduced Flask Charges used".

Also, use Divine Orbs, Omen of the Blessed, etc. to make sure BOTH(explicit and implicit) 'reduced Flask Charges used' rolls are maxed out. max rolls are require to get 80% reduced flask charges used.

-Prefixes (in order of priority)

1. #% chance for Flasks you use to not consume Charges

2. Maximum Mana

3. Increased Charm Effect Duration (Not very important though. Just use whatever you happen to get.)

However, try your best to AVOID maximum Life!

-Suffixes (in order of priority)

1. Reduced Flask Charges used (MANDATORY!)

2. Whatever Resistances you need

3. #% increased Flask Charges gained or Flasks gain Charges per second


[CHARMS]

Forsaken Bangle Amethyst Charm is ABSOLUTELY MANDATORY!

The higher the Duration and Quality, the better.

+ For Rite of Passage, I think the Cat version is the best, but using other version is completely fine as well.

For the remaining slot, you can use whatever you prefer. Personally, I recommend a magic Thawing Charm.


[FLASKS]

Melting Maelstrom Mana Flask is MANDATORY! This is the Core mechanic of the build and the Engine.

The lower the Duration, the better.

For your Life Flask, just use any flask with Instant Recovery.


[UNIQUE JEWELS]

Split Personality Sorceress version is MANDATORY!

(How to use Split Personality: Connect your Passive Tree all the way to the Sorceress starting point at 12 o'clock, then socket Split Personality into the Jewel Socket above it. You can then unallocate the passives leading from the Mercenary starting point at 6 o'clock.)

Prism of Belief is set up around +2 Levels to Ice Nova.

There's no need to spend a ton of currency on a +3 version. I recommend simply using a +2 version. That's already enough to reach Level 40.

+If you have enough budget, get Voices together as well ofc


[RARE JEWELS]

Ideally, you obviously want to use 5-mod Jewels with 3 suffixes.

-Prefixes (in order of priority)

1. Increased Effect of Suffix Modifiers

2. Triggered Spells deal #% increased Spell Damage

3. #% increased Spell Damage

-Suffixes (in order of priority)

1. Increased Critical Spell Damage Bonus

2. Increased Critical Hit Chance for Spells

3. Increased Critical Damage Bonus

4. Increased Critical Hit Chance

Skill Gems

Support Gem Requirements:

Str 45

Dex 5

Int 40

1

Virtuous Barrier

Level 20

2

The Stars Answer

Level 19

3

Cast on Block

Level 20

icenovaplayer
supportdiallasdesireplayer
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4

Raise Shield

Level 1

5

Cast on Dodge

Level 20

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6

Magma Barrier

Level 10

7

Cast on Dodge

Level 20

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8

Sacrifice

Level 20

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9

Archmage

Level 20

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10

Remnants of Kalguur

Level 20

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11

Skeletal Cleric

Level 13

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Gem Priority
+25

If you're using a Svalinn with a 4-link Cast on Block setup, the support gem priority goes from top to bottom.

For Skeletal Cleric and Magma Barrier, use the lowest-level gems possible!

For Ice Nova, make sure to use a double-corrupted Level 21 / 23% Quality gem.

For the rest of the gems, you don't really need to go out of your way to get 23% Quality versions. (Obviously, it's still better if you do tho.)

Unless you have currency to burn, I recommend simply not using Uhtred's Augury and Uhtred's Omen Lineage Support Gem.

Eternal March, it's also slightly better if you adjust its gem level appropriately, but honestly, it doesn't matter that much. I couldn't be bothered either, so I'm just using a Level 21 one myself.

+slightly adjust numbers of red and blue support gems depending on your setup, it's because you wanna get both red and blue bonus from Gem Studded

Passive Tree

main:
123
123
set 1:
20
20
set 2:
20
20

If you're short on Passive Points, remove the Crit-related passive nodes first.

I don't recommend removing the other passives, as many of them are tied directly to the build's core mechanics.

Also, You're suppossed to proc Ice Nova per every 2 block (Cast on Block).

If you can't do it because you're using lower level Cast on Block, then adjust your passive tree to generate slightly more energy

Quest Rewards

Check which quests you’ve completed on your character
Clearfell — Beira of the Rotten Pack
+10% to Cold Resistance
Hunting Grounds — The Crowbell
Grants Two Weapon Set Passive Skill Points
Freythorn — The King in the Mists
+30 to Spirit
Ogham Farmlands — Una's Hut
Grants Two Weapon Set Passive Skill Points
Ogham Manor — Candlemass, the Living Rite
+20 to maximum Life
Keth — Kabala, Constrictor Queen
Grants Two Weapon Set Passive Skill Points
Valley of the Titans — Medallion
30% increased Charm Charges gained
+1 Charm Slot
Deshar — Final Letter
Grants Two Weapon Set Passive Skill Points
The Spires of Deshar — Sisters of Garukhan
+10% to Lightning Resistance
Jungle Ruins — Mighty Silverfist
Grants Two Weapon Set Passive Skill Points
The Venom Crypts — Venom Draught
25% increased Mana Regeneration Rate
Jiquani's Machinarium — Blackjaw, the Remnant
+10% to Fire Resistance
The Azak Bog — Ignagduk, the Bog Witch
+30 to Spirit
The Molten Vault — The Molten Vault
Reforging Bench
Aggorat — Blood Sacrifice
Grants Two Weapon Set Passive Skill Points
Journey's End — Captain Hartlin
Two Weapon Set Passive Skill Points
Skill Gem(Lv 13)
Delirium Drop
Whakapanu Island — Great White One
Not Specified2 choices
Eye of Hinekora — Navali's Rest
5% increased Maximum Mana
Halls of the Dead — Yama The White
Grants Two Weapon Set Passive Skill Points
Halls of the Dead — Tawhoa's Test
+5% to Lightning Resistance
Abandoned Prison — Goddess of Justice
30% increased Mana Recovery from Flasks
Halls of the Dead — Tasalio's Test
+5% to Cold Resistance
Halls of the Dead — Ngamahu's Test
+5% to Fire Resistance
Halls of the Dead — Tribal Medicine
Not Specified2 choices
Wolvenhold — Oswin, the Dread Warden
Grants Two Weapon Set Passive Skill Points
The Khari Crossing — Akthi and Anundr
Two Weapon Set Passive Skill Points
The Khari Crossing — Molten Shrine
5% increased Maximum Life
Qimah — Tabana's Pillar
+5 to all Attributes
Kriar Village — Lythara, the Wayward Spear
+40 to Spirit
Howling Caves — The Abominable Yeti
Grants Two Weapon Set Passive Skill Points

How it Plays

[HOW TO PLAY]

1. Somehow spam mana flask 20ish times per second

2. Once you enter the map, keep using your Mana Flask and simply also KEEP Dodge Rolling.

(first 9 seconds after you enter the map, you should also keep using life flask as well.)

That's it.

Also, when you wanna leave the map if self-damage from flask cancels your portal, you can simply unequip it and equip again.

+IF YOU'RE CONSIDERING USING 3RD PARTY TOOL, I DO NOT RECOMMEND IT! THERE'S A RISK LOSING YOUR WHOLE ACCOUNT JUST TO PLAY A BUILD

How it Works

[CORE MECHANICS]

Cast on Block does not trigger simply from taking damage. An actual Hit needs to be Blocked for it to trigger, which is why building around Cast on Block as a core mechanic has been practically impossible until now.

However, about a week ago, a Chinese player discovered a way to trigger Cast on Block by yourself.

The answer is the Melting Maelstrom Mana Flask.

When this Mana Flask's duration expires, it deals self-damage equal to 25% of your current Mana. For some reason, this damage is considered a Hit, meaning it can actually be Blocked — and Cast on Block can trigger from it.

Therefore, we:

1. Reduce Mana Flask Charge consumption to an extreme degree,

2. Stack multiple sources of Flask Charge gain,

3. Somehow spam Mana Flask 20 ish times per second

Mana Flask Charge sustain will be stable.

We also push our Block Chance as close to the maximum as possible.

As a result, we can automatically spam skills at least 10+ times per second.

+Skills socketed into Cast on Block don't even consume Mana.

On top of that, we use the effect of the Forsaken Bangle Amethyst Charm to continuously recover massive amounts of both Mana and Life.

And on top of THAT, the Svalinn enchant "Mana Gained When You Block"

So instead of merely recovering enough Mana to cover what we're spending, actually we can continuously recover Mana at an absurd rate, almost infinitely.

We're also using the Mind Over Matter keystone passive node, essentially turning our Mana pool into our Life pool.

This is one of the main reasons why this build's survivability is so ridiculously strong.

Also, remember how I mentioned that skills socketed into Cast on Block don't consume Mana?

That also applies to the additional Mana Cost caused by Archmage.

This means we can gain an enormous amount of extra Lightning Damage from Archmage while completely ignoring its biggest downside: the massive additional Mana Cost.

On top of that, we use the alternate Quality effect of Cast on Dodge to push our already excellent mobility to an even more ridiculous level...

And by socketing the necessary utility skills into it as well, we can create a fully automated system where simply Dodge Rolling automatically triggers everything we need.

We continuously consume Corpses using Bitter Dead, and every time a Corpse is consumed, Gorge grants us a massive amount of Flask Charges.

When there are no Corpses nearby, we use Sacrifice and Skeletal Cleric to make our Minions considered as Corpses.

Then, once those Minions die, Eternal March continuously revives them for us.

However, skills socketed into Cast on Dodge cannot bypass additional mana cost from Archmage, meaning we still have to find a way how to bypass it.

I solved this issue by using Lifetap and Efficiency II, bringing the Mana Cost down to 0.

And lastly, one last thing you need to keep in mind.

Because this build relies on the effect that occurs when the Mana Flask expires, there is a roughly 9-second warm-up period after entering a map.

Changelog

Channel Link to The Original Video That Introduced me This Mana Flask Tech: https://space.bilibili.com/41885366

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