Version

Breakthrough

IroncladAttackCommon
Lose 1 HP.
Deal 9 damage to ALL enemies.

You lose 1 HP first, ignoring Block, then every enemy takes 9 damage (13 upgraded). Because the HP loss comes before the hit, effects that trigger on losing HP resolve first, and a Strength gain from Rupture is already in place for the damage. Strength adds to each enemy's hit.

Character
Ironclad
Type
Attack
Rarity
Common
Cost
1 Energy
Target
All enemies

When to take Breakthrough

Take it in Act 1 for hallway fights against three enemies, where 27 total damage for 1 Energy is excellent. Upgrade it early, 4 extra damage on every enemy is a big jump.

Cards that synergize with Breakthrough

Rupture
Power
1
Whenever you lose HP on your turn, gain 1 Strength.
Rupture gives Strength before the hit lands.Whenever you lose HP on your turn, gain 1 Strength.
Inferno
Power
1
At the start of your turn, lose 1 HP.
Whenever you lose HP on your turn, deal 6 damage to ALL enemies.
Inferno adds 6 more to all enemies for the HP loss.At the start of your turn, lose 1 HP.
Whenever you lose HP on your turn, deal 6 damage to ALL enemies.
Spite
Attack
0
Deal 5 damage.
If you lost HP this turn,
hits 2 times.
Spite hits twice afterward.Deal 5 damage.
If you lost HP this turn,
hits 2 times.
Thunderclap
Attack
1
Deal 4 damage and apply 1 Vulnerable to ALL enemies.
Thunderclap applies Vulnerable to all first.Deal 4 damage and apply 1 Vulnerable to ALL enemies.
Inflame
Power
1
Gain 2 Strength.
Inflame is cheap permanent Strength for every target.Gain 2 Strength.
Tear Asunder
Attack
2
Deal 5 damage.
Hits an additional time for each time you lost HP this combat.
Tear Asunder triggers when you lose HP, and Breakthrough makes you lose someDeal 5 damage.
Hits an additional time for each time you lost HP this combat.

Relics that synergize with Breakthrough

Red Skull
Red Skull adds 3 Strength once you are under half HP.While your HP is at or below 50%, you have 3 additional Strength.
Self-Forming Clay
Self-Forming Clay triggers when you lose HP, and Breakthrough makes you lose someWhenever you lose HP in combat, gain 3 Block next turn.
Demon Tongue
Demon Tongue triggers when you lose HP, and Breakthrough makes you lose someThe first time you lose HP on your turn, heal HP equal to the amount lost.
Centennial Puzzle
Centennial Puzzle triggers when you lose HP, and Breakthrough makes you lose someThe first time you lose HP each combat, draw 3 cards.
✦
Hemokinesis
Attack
1
Lose 2 HP.
Deal 15 damage.
Blood Wall
Skill
2
Lose 2 HP.
Gain 16 Block.
Bloodletting
Skill
0
Lose 3 HP.
Gain .
Crimson Mantle
Power
1
At the start of your turn, lose 1 HP and gain 8 Block.
Inferno
Power
1
At the start of your turn, lose 1 HP.
Whenever you lose HP on your turn, deal 6 damage to ALL enemies.
Brand
Skill
0
Lose 1 HP.
Exhaust 1 card.
Gain 1 Strength.
Demonic Shield
Skill
0
Lose 1 HP.
Give another player Block equal to your Block.
Exhaust.
Offering
Skill
0
Lose 6 HP.
Gain .
Draw 3 cards.
Exhaust.

Changes by version

  1. 19 Mar 2026Bug fixBeta branch
    Fixed a softlock that could occur when a player would die to Breakthrough card's self-HP loss in multiplayer
  2. 10 Apr 2025Bug fixRuptureStrengthInternal playtest
    Rupture power now applies Strength gain after Breakthrough card is finished playing
  3. 6 Feb 2025Bug fixInternal playtest
    Breakthrough card attack animation no longer plays if the player is dead
All 5 patch notes2 older
  1. 9 Jan 2025Damage10(13)9(13)Internal playtest
    Damage decreased from 10 to 9
  2. 10 May 2024DamageInternal playtest
    Breakthrough now causes HP loss before dealing damage to be consistent with other HP loss cards

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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