Test Subject

Boss
Health
100/111 HPAlways 100. 111 from Ascension 8.
Gold
10075 goldAlways 100. 75 from Ascension 3.Always 75. 100 below Ascension 3.
Found in
GloryBoss, alone, 1 in 3 from the boss pool.
Starts with
attack20/22
Test Subject100/100/111/111Test SubjectAdaptable1Enrage2

Turn 1

How to beat Test Subject

  • Skills are the trap: each one feeds Enrage across all 600 HP, so keep them rare and find Block elsewhere.
  • Respawn turn: deals no damage, a free setup turn.
  • Form two: block all of Multi-Claw or eat a Wound per unblocked hit.
  • Form three: hits on an Intangible turn do 1 damage, so burst on the other turns, block 45 for Big Pounce, and play Burns before turn end.

Notes

  • Glory boss; the third death is final.
  • Its name's number is 8 plus a save-file count of its knockdowns.
  • The compendium hides Bite, Skull Bash and Lacerate; Big Pounce ignores Deadly Enemies.

Changes by version

  1. 30 Jul 2026ArtPlaytest
    Added fire to Test Subject burn animation
  2. Fixed Test Subject starting phase 2 with extra Strength when killed by Sleight of Flesh via Enfeebling Touch
    Bug fixv0.107.1
    Fixed several Test Subject issues
    Bug fixv0.107.1
    Corrected Test Subject HP scaling in multiplayer
  3. Fixed Test Subject starting phase 2 with extra strength if it is killed by Sleight of Flesh via Enfeebling Touch
    Bug fixBeta branch
    Fixed a few issues with Test Subject in the Bestiary
    Bug fixBeta branch
    Corrected Test Subject HP scaling in multiplayer
All 34 patch notes31 older
  1. 26 Mar 2026ArtBeta branch
    Added Test Subject burn animation
  2. 19 Mar 2026ChangeBeta branch
    Phase 2 no longer has the Pounce move, instead will repeat Multi Claw move every turn
  3. 26 Feb 2026Phase 3 Lacerate damage11(12)10(11)Internal playtest
    Phase 3 Lacerate damage decreased from 11 to 10 (12 to 11 with Ascension)
  4. 19 Feb 2026BuffInternal playtest
    Buffed Test Subject phase 2 initially hits an additional time
  5. 22 Jan 2026Vulnerable applied21Internal playtest
    Phase 1's Skull Bash move damage decreased from 16 to 14 (18 to 16 with Ascension); Vulnerable applied decreased from 2 to 1; Phase 2 now starts with Multi Claw move instead of Pounce; Phase 3 now applies Intangible at end of turn instead of start
    Bug fixPoisonIntangibleInternal playtest
    Test Subject's Phase 3 now takes full Poison damage on non-Intangible turns
  6. 15 Jan 2026ReworkInternal playtest
    Reworked Test Subject
  7. 8 Jan 2026InterfaceIntangibleInternal playtest
    Made Test Subject opaque again if it is killed while it has Intangible
  8. 1 Jan 2026Bug fixIntangibleInternal playtest
    Fixed Test Subject staying semi-transparent after losing Intangible while stunned
  9. 13 Nov 2025ReworkInternal playtest
    Reworked Test Subject
  10. 9 Oct 2025Bug fixDoomInternal playtest
    A10 Test Subject no longer disappears if it is killed by Doom on its 3rd form
  11. 18 Sep 2025Bug fixPainful StabsWoundThornsInternal playtest
    Test Subject monster's Painful Stabs power now properly gives Wound cards even when its owner dies to Thorns power
    Bug fixInternal playtest
    Test Subject no longer briefly fades out when transitioning between phases
  12. 21 Aug 2025BuffInternal playtest
    Buffed Test Subject
    Bug fixInternal playtest
    Fixed softlock when viewing the victory screen of a run against Test Subject
  13. 14 Aug 2025TextInternal playtest
    Removed speech line from Test Subject boss
  14. 24 Jul 2025SoundInternal playtest
    Added SFX
    SoundInternal playtest
    Added custom Test Subject BGM
    Bug fixHangInternal playtest
    Hang power no longer applies to Test Subject when it is killed first
  15. 10 Jul 2025ReworkInternal playtest
    Reworked Test Subject
  16. 26 Jun 2025Bug fixInternal playtest
    Fixed an issue where Test Subject's Malleable power wasn't giving it enough block after multi-hit attacks
  17. 20 Jun 2025Bug fixTanx's WhistleInternal playtest
    Fixed Test Subject being unhittable if it is killed while it is stunned by Tanx's Whistle card
  18. 5 Jun 2025Bug fixBeetle JuiceInternal playtest
    Fixed an issue where, after shrinking Test Subject in phase 1 or 2 with Beetle Juice and then killing it, it would stay visually shrunk
  19. 25 Apr 2025Bug fixInternal playtest
    Fixed issue where Lightning orb would softlock on dead Test Subject
    Bug fixInternal playtest
    Playing an AOE attack while Test Subject is downed no longer makes the attack stuck
  20. 17 Apr 2025InterfaceInternal playtest
    Test Subject now gets bigger as he respawns
  21. 10 Apr 2025Bug fixInternal playtest
    Test Subject boss now uses correct death/revival animation in multiplayer
  22. 13 Mar 2025ArtInternal playtest
    Added Test Subject boss animations
  23. 27 Feb 2025Bug fixDoomInternal playtest
    Fixed an issue that caused Test Subject to softlock if you killed him with Doom before he reached his final form
  24. 6 Feb 2025RemovedInternal playtest
    Deprecated Test Subject's Mutating Ichor card
  25. 23 Jan 2025Bug fixSlyCalculated GambleInternal playtest
    Fixed a softlock when killing Test Subject by discarding a hand full of Sly cards via Calculated Gamble
  26. 16 Jan 2025Bug fixAdaptableInternal playtest
    Test Subject can no longer be hit by AOE when Adaptable activates
    Bug fixAdaptableInternal playtest
    Test Subject no longer finishes multi-hit if Adaptable procs on the first hit
    Bug fixAdaptableInternal playtest
    Test Subject no longer becomes invincible if Adaptable triggers off of Perfect Reflection power
  27. 9 Jan 2025ReworkInternal playtest
    Reworked enemies/combats
  28. 12 Dec 2024Bug fixInternal playtest
    Test Subject no longer shuffles status cards to the bottom of the draw pile
  29. 5 Dec 2024ChangeInternal playtest
    Now adds cards to Draw Pile instead of hand
    Bug fixInternal playtest
    Fix misaligned Block indicator when hitting the Test Subject many times in sequence
  30. 21 Nov 2024Bug fixInternal playtest
    Test Subject now has Malleable instead of Mutegenic Adaptation
    Bug fixInternal playtest
    Test Subject's new status is Mutating Ichor: if this is in your hand at the end of your turn, Test Subject gains 1 strength
  31. 23 Aug 2024AddedInternal playtest
    Added to the game

Internal playtest notes are from before the Early Access release. Names and numbers in them can differ from the game today.

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