CWDT PoE Setup, Cast when Damage Taken Support Build

Related Gems

Level Effect

Skill functions and interactions

Trigger gem: Like all trigger gems, Cast when Damage Taken only "casts" spells. Attack gems such as Double Strike are not considered spells. Multiple spells can be linked to a single trigger gem, and will all be triggered if so. Multiple copies of Cast when Damage Taken will also function independently.

Damage counter and cooldown: Each linked spell gains an internal damage counter that tracks the total accumulated damage taken from hits, though not from damage over time or the Blood Magic passive (e.g. you cannot use Righteous Fire to trigger Cast when Damage Taken). All damage counters will be reset to 0 upon entering a new area. When a linked spell is cast, it is put on cooldown for 250 ms and will not track damage during that time.

Multiple copies of the same gem share cooldowns, meaning that if two copies of the same spell are triggered within 250 ms of each other, the first will trigger and the second will fail to do so as it is on cooldown. This mostly prevents using multiple copies of the same spell with Cast when Damage Taken, though the use of Cast when Damage Taken gems of different levels can avoid cooldown overlap in some circumstances due to the differing amounts of damage required to trigger the spells.

The Cast when Damage Taken gem itself does not have its own counter or cooldown.

Maximum level of supported skills: Cast when Damage Taken cannot support skills with a higher player level requirement than that of Cast when Damage Taken itself. Note that this restriction only applies to active skills; any level of other support gems may be used.

Trigger order: Trigger gems and their linked skills are cast in a certain order that depends both on which item it is equipped on and which socket the skills are in. If there are trigger gems in each equipped item, the order of operation will be:

Main hand ⇒ Amulet ⇒ Helm ⇒ Off hand ⇒ Body armour ⇒ Gloves ⇒ Boots

The linked sockets also follow a specific order, as follows:

Damage effectiveness: The damage effectiveness increases with level, but so does the damage taken per cast; overall, the amount of damage that needs to be taken per damage effectiveness goes up at higher gem levels. The optimum is a level 2 gem, which requires 1442 damage taken per 100% damage effectiveness. In comparison, a level 20 gem requires 3057 damage taken per 100% damage effectiveness.

This does not, however, take into account the increase in damage from being able to use a higher level gem; for instance, a level 4 Bladefall gem deals an average of 91.5 damage, while a level 20 gem deals an average of 475. On a strict damage-in-per-damage-out basis, Cast when Damage Taken roughly triples in power between level 1 and level 20, depending on the skill used. Any flat added damage will affect this ratio—the more damage added, the less effective it is to level up the Cast when Damage Taken gem.

Targeting: Targeted spells will cast towards the enemy that caused the last damage. Reflected damage is considered to come from the enemy originally damaged. If the damage was self-caused, it will target a random enemy (if there are no enemies, it will be cast at the player, if it is a projectile, it will be fired in a random direction).

Totems: Cast when Damage Taken can't be used with totems.

Item acquisition

Cast when Damage Taken Support can drop anywhere. Drop level: 38.

Recipes

Cast when Damage Taken Support can be created from the following recipes:

Vendor reward

This item can be bought at the listed NPC vendors, after completing the following quests:

Related unique items

The following unique items are related to Cast when Damage Taken Support:

Strategy

Due to the large amount of damage taken needed per damage effectiveness and the rapid scaling of damage taken required per level, it is advisable to use spells for purposes other than damage that do not depend heavily on the active skill level. Possible choices include:

Offensive:

• Wave of Conviction for applying Exposure
• Frost Bomb for applying Cold Exposure and reducing enemies' Life/Energy Shield regen
• Cold Snap for Frenzy Charge generation
• Offensive curses such as Frostbite, Flammability, Conductivity, Elemental Weakness, Despair, Vulnerability, etc.
• Offensive golems such as Summon Ice Golem, Summon Flame Golem, Summon Lightning Golem

Defensive:

• Guard skills such as Immortal Call, Steelskin, Molten Shell, Arcane Cloak, Frost Shield
  • Only one guard skill should be used in all CWDT setups, as they share their cooldown
  • Increased Duration Support can be used to increase the duration
• Withering Step for Elusive and Phasing.
• Phase Run for increased movement speed, reduced visibility and Phasing
  • Useful for builds that often run past packs such as minion or DOT builds
  • Make sure Phase Run is the last skill to be triggered in all CWDT setups
• Frost Wall to block enemies.
• Void Sphere to Hinder enemies.
• Vortex, Creeping Frost or Cold Snap to chill enemies.
  • Can be linked with Bonechill Support for increased chill effect
• Purifying Flame to create Consecrated Ground
• Detonate Dead, Flesh Offering, or Bone Offering for passive corpse disposal and minion buffing
• Lightning Warp to escape melee range (could backfire).
• Defensive curses such as Enfeeble, Temporal Chains
• Defensive golems such as Summon Stone Golem, Summon Chaos Golem.
  • Can be linked with Meat Shield Support

Other:

• Portal for builds that die often.
• Lightning Warp is often used in AFK boss kill attempts such as Uber Elder or Sirus.

Some supports also potentially combine well, especially with a persistent rapid-firing skill such as Ball Lightning:

• Blind Support
• Chance to Flee Support
• Passive IIR culling via Culling Strike Support, Item Rarity Support, and a skill that causes many hits.
• Hextouch Support (As of Version 1.2.2 CWDT will only trigger Ball Lightning in this example, Ball Lightning will then only trigger Hextouch if the supported curse is above the CWDT level threshold.)
• Knockback Support
• Power Charge On Critical Support

With self-damaging mechanics, it is possible to cause spells created from CWDT to proc CWDT again, creating a loop. Some possibilities are:

• Scold's Bridle
  • Pros: stable output; you can tune proc rate by changing mana cost; only one item required
  • Cons: requires fast recovery to mitigate damage taken. Otherwise, you can kill yourself in your hideout just by testing skills. Usually Agnostic Pathfinder with mana flask, Clarity watcher's eye mod, Battle Rouse

• Heartbound Loop
  • Pros: stable output
  • Cons: same as Scold's + huge waste of jewel sockets

• Eye of Innocence
  • Pros: great recovery (at worst you take damage as frequently as you gain HP back); many recovery options: Vitality mod, Discipline mod, Ngamahu's Sign, Razor of the Seventh Sun, Shaper rings
  • Cons: 100% chance to ignite forces passive tree/ascendancy choices; easier to get best proc rates against packs than against single targets

• Replica Tulfall
  • Pros: stable recovery, you can adapt to bad map mods by changing a number of socketed Powerlessness jewels
  • Cons: Pathfinder mana or tons of unique items to get HP recovery, better proc rates against packs than single target

• Gluttony or Hiltless
  • Pros: one item
  • Cons: requires external life recovery, low trigger rate (enough to proc Vengeance)

• Storm Secret
• Doedre's Elixir
• Forbidden Rite

Quick reference chart of commonly used spell gems and their maximum allowed level to be supported by each level of CWDT: