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
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
Kin Priest
A trio fight: the Kin Priest hides behind two Kin Followers, applying debuffs while its minions deal escalating damage.
Trio Fight
Act 1b: Underdocks
3 bosses — one is chosen at random each run
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
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
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
Act 2: Hive
3 bosses — one is chosen at random each run
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
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
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
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
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)
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