Template:Gem Infobox
Cast when Damage Taken is a trigger gem. It causes a linked spell to activate when the player accumulates damage taken.
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 but if two or more spells are of the same type (e.g.: Cast when Damage Taken - Fireball - Fireball) they will never trigger simultaneously, even if they are not on the same link. The order in which they are linked determines the order in which they cast. The top end of the linked sockets (for four-links, the top left socket) is the first in the order, followed by each socket down the line, following links.
Damage Counter and Cooldown: Each linked skill has an internal damage counter that tracks the total accumulated damage taken from hits, but not from damage over time or the Blood Magic passive[1] (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 skill is cast, its damage counter will go on cooldown for 250 ms and will not track damage during that time. Furthermore, Cast when Damage Taken has its own cooldown of 250 ms, and a linked skill can only be cast when both its own damage counter and Cast when Damage Taken are not on cooldown. This can cause skills intended to be simultaneous to get out of sync.
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.
Targeting: Targeted spells will cast towards the enemy that caused the last damage. Reflected damage is considered to come from the enemy originally damaged.
Maximum Level of Supported Skills: Cast when Damage Taken cannot support skills of higher level than specified. Note that this restriction only applies to active skills; any level of supports may be used.
Totems Cast when Damage Taken can't be used with Totems, but it can be used with Module Error: No skills found with q_where = skill.active_skill_name="Spell Totem" since it's a support gem for another spell (like 
Summon Skeletons)
Gem level progression
Template:GemLevelTable |- ! 1 | 38 | 40 | 27 | 528 | 70% | 38 | 0 | 0 |- ! 2 | 40 | 41 | 29 | 583 | 66% | 40 | 388,734 | 388,734 |- ! 3 | 42 | 43 | 30 | 661 | 62% | 42 | 477,437 | 866,171 |- ! 4 | 44 | 45 | 31 | 725 | 58% | 44 | 583,786 | 1,449,957 |- ! 5 | 46 | 47 | 33 | 812 | 54% | 46 | 710,359 | 2,160,316 |- ! 6 | 48 | 49 | 34 | 897 | 50% | 48 | 1,355,511 | 3,515,827 |- ! 7 | 50 | 51 | 35 | 1003 | 46% | 50 | 1,138,877 | 4,654,704 |- ! 8 | 52 | 53 | 37 | 1107 | 42% | 52 | 1,368,233 | 6,022,937 |- ! 9 | 54 | 55 | 38 | 1221 | 38% | 54 | 1,638,338 | 7,661,275 |- ! 10 | 56 | 57 | 39 | 1354 | 34% | 56 | 1,956,648 | 9,617,923 |- ! 11 | 58 | 58 | 41 | 1485 | 30% | 58 | 3,655,184 | 13,273,107 |- ! 12 | 60 | 60 | 42 | 1635 | 26% | 60 | 3,017,327 | 16,290,434 |- ! 13 | 62 | 62 | 43 | 1804 | 22% | 62 | 3,576,232 | 19,866,666 |- ! 14 | 64 | 64 | 44 | 1980 | 18% | 64 | 4,231,667 | 24,098,333 |- ! 15 | 65 | 65 | 45 | 2184 | 14% | 65 | 2,395,078 | 26,493,411 |- ! 16 | 66 | 66 | 46 | 2394 | 10% | 66 | 8,421,063 | 34,914,474 |- ! 17 | 67 | 67 | 46 | 2621 | 6% | 67 | 16,159,983 | 51,074,457 |- ! 18 | 68 | 68 | 47 | 2874 | 2% | 68 | 41,170,367 | 92,244,824 |- ! 19 | 69 | 69 | 48 | 3142 | 2% | 69 | 86,794,448 | 179,039,272 |- ! 20 | 70 | 70 | 48 | 3272 | 6% | 70 | 157,405,063 | 336,444,335 |- ! 21 | 72 | 72 | 50 | 3580 | 10% | 72 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |- ! 22 | 74 | | | 3950 | 14% | 74 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |- ! 23 | 76 | | | 4350 | 18% | 76 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |- ! 24 | 78 | | | 4780 | 22% | 78 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |- ! 25 | 80 | | | 5240 | 26% | 80 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |- ! 26 | 82 | | | 5730 | 30% | 82 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |- ! 27 | 84 | | | 6250 | 34% | 84 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |- ! 28 | 86 | | | 6800 | 38% | 86 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |- ! 29 | 88 | | | 7380 | 42% | 88 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |- ! 30 | 90 | | | 7990 | 46% | 90 | class="table-na" style="text-align: center; " | N/A | class="table-na" style="text-align: center; " | N/A |}
Quest reward
Lua error in Module:Quest_reward at line 157: type must be either quest_rewards or vendor_rewards.
Vendor reward
Lua error in Module:Quest_reward at line 157: type must be either quest_rewards or vendor_rewards.
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:
Immortal Call
Frost Wall to block enemies.- Module Error: No skills found with q_where = skill.active_skill_name="Arctic Breath" to create ground ice.
- Passive corpse disposal/minion buffing via
Detonate Dead, Module Error: Too many skills found with q_where = skill.active_skill_name="Flesh Offering". Please choose only one of the following ids:
FleshOffering - Base duration is 5 seconds, Grants Minions (20-30)% increased Attack Speed, Grants Minions (20-29)% increased Movement Speed, Grants Minions (20-30)% increased Cast Speed, Additional 1 seconds Base Duration per extra corpse Consumed (page)
FleshOfferingTriggeredUnique - Base duration is 5 seconds, Grants Minions 30% increased Attack Speed, Grants Minions 29% increased Movement Speed, Grants Minions 30% increased Cast Speed, Additional 1 seconds Base Duration per extra corpse Consumed, Your Offering Skills also affect you, This Skill is Triggered by the Item granting it, You cannot Cast this Spell directly (page), or Module Error: Too many skills found with q_where = skill.active_skill_name="Bone Offering". Please choose only one of the following ids:
BoneOffering - Base duration is 5 seconds, Grants Minions +(25-35)% Chance to Block Attack Damage, Grants Minions +(25-34)% Chance to Block Spell Damage, Additional 1 seconds Base Duration per extra corpse Consumed, Minions recover (11-594) Life when they Block (page)
BoneOfferingTriggeredUnique - Base duration is 5 seconds, Grants Minions +35% Chance to Block Attack Damage, Grants Minions +34% Chance to Block Spell Damage, Additional 1 seconds Base Duration per extra corpse Consumed, Minions recover 594 Life when they Block, Your Offering Skills also affect you, This Skill is Triggered by the Item granting it, You cannot Cast this Spell directly (page). - Lightning Warp to escape melee range. (Could backfire.)
- Curses. This can be a reliable way of automatically casting curses, at the cost of lower curse level.
Some supports also potentially combine well, especially with a persistent rapid-firing skill such as 
Ball Lightning:
- Module Error: No skills found with q_where = skill.active_skill_name="Blind"
- Module Error: No skills found with q_where = skill.active_skill_name="Chance to Flee"
- Passive IIR culling via Module Error: No skills found with q_where = skill.active_skill_name="Culling Strike", Module Error: No skills found with q_where = skill.active_skill_name="Item Rarity", and a skill that causes many hits.
- Module Error: No skills found with q_where = skill.active_skill_name="Curse on Hit"
- Module Error: No skills found with q_where = skill.active_skill_name="Knockback"
- Module Error: No skills found with q_where = skill.active_skill_name="Power Charge On Critical"
Cats when Damage Taken
Cats when Damage Taken was a trigger gem available only on April 1st 2015. It was a bug caused by a typo in source code[2]. Like Cast when Damage Taken, it caused a linked spell to activate when the player accumulated damage taken, but besides casting the spell, it also summoned black cats. Other properties were identical to the Cast when Damage Taken skill.
Cats spawned by Cats when Damage Taken
Version history
| Version | Changes |
|---|---|
| 2.0.0 |
|
| 1.3.1g |
|
| 1.3.1 |
|
| 1.3.0 |
|
| 1.2.2 |
|
| 1.0.1 |
|
| 1.0.0f |
|
| 1.0.0 |
|
See also
- Module Error: No skills found with q_where = skill.active_skill_name="Cast on Death"
- Module Error: No skills found with q_where = skill.active_skill_name="Cast on Critical Strike"
- Module Error: No skills found with q_where = skill.active_skill_name="Cast on Melee Kill"
References
- ↑ Mark_GGG (9 October 2013). "Path of Exile Forum". Retrieved 2 July 2015.
- ↑ Chris (April 1, 2015). "Incident Report for April 1 Catastrophe". Retrieved April 1, 2015.
Cast when Damage Taken Support
