Boss Guide
Every boss in Slay the Spire 2 — HP values, attack patterns, key mechanics, and strategies to beat them. One random boss per act from that act's pool.
Act 1a: Overgrowth
3 bosses — one is chosen at random each run

Kin Priest
A trio fight: the Kin Priest hides behind two Kin Followers, applying debuffs while its minions deal escalating damage.
Trio Fight

Vantom
A shadow creature that shields itself with Slippery stacks, absorbing your first hits before revealing its true vulnerability.
Slippery

Ceremonial Beast
A two-phase beast that ramps damage with Strength and punishes you with the Ringing debuff when stunned.
Plow / Stun
Act 1b: Underdocks
3 bosses — one is chosen at random each run

Waterfall Giant
A slow but inevitable threat that builds Steam Eruption stacks throughout the fight. When killed, it explodes for damage equal to all accumulated steam.
Steam Eruption

Soul Fysh
A rhythm-based boss that cycles between attacks, Beckon status cards, and Intangible windows on a strict 5-turn rotation.
Beckon / Intangible Cycle

Lagavulin Matriarch
Starts the fight asleep behind 12 Plating. Once awake, she debuffs your Strength and Dexterity every cycle, making the fight progressively harder.
Sleep / Plating
Act 2: Hive
3 bosses — one is chosen at random each run

Knowledge Demon
Forces you to choose between escalating Curse cards every cycle, each one more punishing than the last. A war of attrition that tests your deck's resilience.
Curse of Knowledge

Kaiser Crab
A two-target boss fight against the Crusher claw (199 HP) and Rocket claw (189 HP). Destroying both claws wins the fight — the body flees.
Dual Claws / Positioning

The Insatiable
A terrifying sand worm with an instant-kill timer. The Sandpit counter ticks down every turn — when it hits zero, you're devoured. Frantic Escape cards buy time, but using too many slows your damage.
Sandpit / Frantic Escape
Act 3: Glory
3 bosses — one is chosen at random each run

Test Subject #C8
A three-phase boss that revives twice with increasing HP (100 → 200 → 300) and different modifiers each phase. Adapts to punish your strategy.
Adaptable (3 Phases)

Doormaker
A two-phase repeating boss: you break through the Door (155 HP), then face the Doormaker itself. It cycles between Door and Doormaker forms, gaining Strength each cycle.
Door / Doormaker Phase Cycle

Queen
Accompanied by the Torch Head Amalgam (199 HP), the Queen cripples your hand with Afflictions and buffs her minion into a killing machine.
Chains of Binding / Afflictions
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