Slay the Spire 2 Boss

Ceremonial Beast Boss Guide

Boss • Act 1 - Overgrowth
Base HP
252
Ascension HP
262
Moves
6
Encounters
1
Boss Strategy

How to Beat Ceremonial Beast

Quick Strategy

Treat Ceremonial Beast as a phase-change race. The dangerous part is Phase 1: on Ascension, Plow hits for 20 and gives the Beast 2 Strength every turn, so trying to block indefinitely becomes worse every cycle. Push it to 160 HP as quickly as your deck safely can to trigger the Stun and enter the much more manageable second phase. After the transition, Beast Cry applies Ringing, which makes the following 17-damage Stomp turn a one-card problem. Keep one dense defensive card, enough HP to absorb the hit, or another single-card answer ready for that window. Necrobinder Doom needs special preparation because Doom alone does not trigger the HP-based phase change.

What This Fight Tests

Phase-one damage

The deck needs enough frontloaded damage to remove roughly the first 100 HP quickly. Every extra Plow before the transition deals meaningful damage and adds more Strength, making the next Plow harder to cover.

Single-card defense

After Beast Cry applies Ringing, the following Stomp turn can force the deck to solve the attack with only one card. Several small defensive cards are much less useful than one high-impact answer.

Phase-change access

The transition is tied to reducing the Beast to the phase threshold. Damage plans that do not actually reduce current HP in the normal way can require a separate physical-damage solution to reach Phase 2.

HP buffer

The first phase is difficult to block perfectly, and the Ringing Stomp is awkward even after the transition. Entering with enough HP gives the deck room to prioritize damage early and survive a constrained turn later.

Key Decisions

Phase 1 is the real damage race

I do not plan to settle into a long defensive loop before the phase change. Plow deals 20 on Ascension and adds 2 Strength every time, so every delayed transition increases both current and future damage. The safest defensive improvement is often simply reaching 160 HP sooner.

Do not over-block at the cost of missing the phase change

Perfectly blocking one Plow can be worse than taking controlled HP loss if spending that Energy on damage triggers the transition a turn earlier. The Stun after the phase change gives the deck breathing room, so I compare the HP lost now against the entire extra strengthened Plow I can avoid.

Ringing rewards one dense card

The Ringing turn is not a normal Block-density test. If I can only play one card, a high-impact defensive card is dramatically better than a hand containing several small Blocks. Blood Wall and Leg Sweep are strong examples because one draw can solve most or all of the turn by itself.

17 HP is a meaningful Ringing threshold

The first post-Beast-Cry attack is 17 damage on Ascension. If I cannot reliably produce enough defense with one card, staying above 17 HP gives me a simple fallback: survive the restricted turn and continue the much easier second-phase cycle.

Doom alone does not solve Phase 1

For Necrobinder, Doom can be excellent damage overall but it does not trigger the normal HP-based phase transition by itself. If the deck is almost entirely Doom, I want additional direct physical damage specifically so I can force Ceremonial Beast out of its scaling first phase.

Combat Data

Moves

6 moves

Stun

Stun
STUN

Stomp

Attack
STOMP
Damage
15 → 17
Enemy AI

Attack Pattern

Cycle

Stamp → Plow → repeat

Initial move: Stamp
View pattern states
Stamp
move
Next: PLOW_MOVE
Plow
move
Next: PLOW_MOVE
Stun
move
Next: BEAST_CRY_MOVE
Must perform once
Stomp
move
Next: CRUSH_MOVE
Crush
move
Next: BEAST_CRY_MOVE
Beast Cry
move
Next: STOMP_MOVE
Fight Plan

Ceremonial Beast Fight Plan

The raw move pattern tells you what is coming. This plan focuses on what I want the deck to accomplish before each dangerous part of the fight.

Phase 01

Race the first phase

Push Ceremonial Beast from 262 Ascension HP to the 160-HP phase threshold before repeated Plows scale out of control.

  • Prioritize meaningful frontloaded damage immediately. The first phase is not where I want to spend several turns assembling optional long-term setup.
  • Use offensive scaling that pays back quickly enough to help reach 160 HP. A Power can be correct, but only when the setup actually shortens the phase instead of delaying damage for several turns.
  • Accept controlled HP loss when the alternative is spending the entire turn blocking and allowing another strengthened Plow cycle.
  • Use Vulnerable, offensive potions, or other burst resources when they move the phase transition forward by a full turn.
Watch for
  • Trying to perfect-block every Plow while dealing too little damage to reach 160 HP.
  • Playing several slow setup cards because this is technically a Boss fight even though the immediate problem is frontloaded damage.
Phase 02

Phase transition and Beast Cry

Use the Stun to stabilize, then prepare one high-impact answer for the Ringing-constrained Stomp.

  • Use the phase-change Stun as the first real recovery and setup window. This is a much safer place for additional scaling than the repeated-Plow phase.
  • When Beast Cry appears, look ahead to the following Stomp instead of spending every resource on offense. Ringing means card count will not rescue a weak defensive hand.
  • Retain or preserve a dense Block, Weak, or other one-card mitigation answer when the deck supports it.
  • If no single-card defensive answer exists, protect the HP buffer. Being above the expected 17 damage can be the practical solution.
Watch for
  • Treating Beast Cry as a completely free setup turn and forgetting that Ringing changes the next turn’s card-play limit.
  • Keeping several small Block cards for Stomp when only one of them will actually be usable.
Phase 03

Manage the second-phase cycle

Finish through Beast Cry → Stomp → Crush before repeated Strength gains make the easier phase dangerous again.

  • After the Ringing Stomp, use normal multi-card turns to re-establish damage and defense before Crush.
  • Respect Crush because it deals 19 on Ascension and grants 3 Strength. The second phase is easier than Phase 1, but it is not infinite.
  • Use Beast Cry turns for high-value offensive conversion once the defensive answer for the following Stomp is already secured.
  • If the Boss is inside lethal range, finish instead of preserving resources for another complete Ringing cycle.
Watch for
  • Assuming Phase 2 can be stalled forever because Beast Cry itself does not attack.
  • Using the one-card Ringing turn for low-impact setup when immediate survival is not already secured.

Dangerous Turns & Windows

Danger Window
Repeated Plow

Before the phase change, Ceremonial Beast repeatedly uses Plow. On Ascension it deals 20 damage and gains 2 Strength, so each additional turn makes the next attack harder to defend.

Response: Treat damage as defense. Concentrate enough frontload to reach the 160-HP phase threshold before repeated Strength growth turns the first phase into an unwinnable Block check.
Danger Window
160-HP phase transition

The entire difficulty profile changes once the Beast reaches the phase threshold. Failing to trigger it on a turn where lethal damage pressure is already building can cost another strengthened Plow.

Response: Track the threshold explicitly. When a potion, Vulnerable application, or aggressive line can cross 160 this turn, value the avoided future Plow rather than only the immediate damage number.
Danger Window
Beast Cry

Beast Cry applies Ringing. The attack itself is delayed, but the debuff constrains the following turn so that a normal hand containing several useful cards may still have only one meaningful play.

Response: Prepare a single dense defensive card, Weak application, or sufficient HP rather than relying on several small cards to combine into the answer.
Danger Window
Ringing Stomp

Stomp deals 17 on Ascension immediately after the Ringing setup. The problem is not the raw damage alone; it is having to solve the turn under the one-card restriction.

Response: Use the highest-impact defensive action available. If the deck cannot reliably block it with one card, maintain more than 17 HP so the hit itself does not end the run.
Danger Window
Crush

Crush deals 19 on Ascension and gives Ceremonial Beast 3 Strength, making later cycles progressively stronger.

Response: Use the easier second-phase windows to finish the fight rather than repeatedly cycling Beast Cry, Stomp, and Crush until Strength becomes another scaling problem.
Before the Fight

How to Prepare for Ceremonial Beast

I use these checks before committing the final rewards, upgrades, shop purchases, and potions leading into the Boss.

FrontloadCritical

Can I push 262 HP down to 160 quickly?

Ready when

The deck has enough immediate damage, Vulnerable, scaling that comes online quickly, or offensive potion support to force the phase change before several strengthened Plows occur.

Warning

A deck with strong theoretical long-fight scaling can still lose if it spends too many turns setting up during the repeated 20-damage phase.

Ringing defenseCritical

What is my one-card answer to Stomp?

Ready when

At least one card can provide enough Block, Weak, mitigation, or another defensive effect to cover most of the 17-damage Ringing turn by itself.

Warning

Three small Blocks do not equal one large Block when Ringing allows only one card to be played.

HPHigh

Can I survive an imperfect first phase and the Ringing turn?

Ready when

Current HP permits some controlled Plow leakage while still remaining above the post-transition danger threshold.

Warning

Entering very low HP forces the deck to over-defend Phase 1 and removes the option to simply absorb part of the constrained Stomp turn.

DebuffHigh

Can Weak or Vulnerable improve the important window?

Ready when

Weak can reduce an awkward defensive turn or Vulnerable can accelerate the push to 160 enough to skip another Plow.

Warning

Using a debuff without changing the phase timing or survival calculation may provide less value than saving it for the turn where it actually changes the result.

Damage typeHigh

Does my damage actually trigger the phase change?

Ready when

The deck has enough direct damage to reduce Ceremonial Beast through the 160-HP threshold instead of relying exclusively on a mechanic that does not trigger the transition.

Warning

This is especially important for Doom-heavy Necrobinder decks, which can otherwise remain trapped in the rapidly scaling first phase.

PotionMedium

Can a potion move the phase transition one turn earlier?

Ready when

Fire, Attack, Vulnerable, scaling, or another relevant potion can provide enough immediate output to cross 160 before another Plow.

Warning

The value of the potion is larger than its printed damage when using it also removes an entire future strengthened attack from the fight.

Character Matchups

Ceremonial Beast by Character

The Boss does not change between characters, but the part of the fight that matters most often does. These notes focus on what each character should adjust rather than repeating the general strategy.

Ironclad can often handle the Ceremonial Beast damage race well because strong frontload helps force the phase change quickly. Blood Wall is particularly valuable after the transition because Ringing rewards solving the Stomp with one dense defensive card rather than assembling Block from several plays.

Prioritize
  • Push physical damage aggressively enough to reach the 160-HP threshold before repeated Plow Strength scaling becomes difficult to manage.
  • Treat Blood Wall and other dense one-card defense as premium answers to the Ringing Stomp.
  • Use Vulnerable or offensive resources when they convert directly into an earlier phase transition.
  • Do not spend the whole first phase building a scaling ceiling when the current deck already has enough damage to force the safer phase.
Watch for
  • Over-defending Plow when a more aggressive line would trigger the phase change this turn.
  • Relying on several cheap Block cards to solve a Ringing turn where only one card can be played.

Silent needs enough frontload to reach the phase threshold, but the most matchup-specific tool is Leg Sweep. Ringing turns a normal defensive hand into a one-card decision, and Leg Sweep combines dense Block with Weak in exactly that format.

Prioritize
  • Do not enter the Boss with only slow scaling damage; make sure the deck can actually force the first phase quickly.
  • Preserve Leg Sweep or another dense defensive answer for the Ringing Stomp when possible.
  • Use Weak efficiently when it meaningfully reduces the one-card defensive requirement.
  • Use offensive potions or Vulnerable support when the current physical damage package is just short of a one-turn-earlier phase change.
Watch for
  • Assuming draw and many small defensive cards automatically solve Ringing when card plays themselves are restricted.
  • Investing too heavily in slow scaling while Ceremonial Beast gains Strength every first-phase turn.

Necrobinder has the most important matchup exception: Doom by itself does not trigger Ceremonial Beast’s phase change. A deck that normally relies almost entirely on Doom can therefore remain stuck in the repeatedly strengthening Plow phase far longer than intended. Keep the Doom plan, but add enough direct physical damage to force the 160-HP transition.

Prioritize
  • Draft or preserve direct damage when Ceremonial Beast is the Act Boss, even if the rest of the deck is strongly committed to Doom.
  • Use physical damage specifically to force the 160-HP phase transition rather than expecting Doom alone to move the fight forward.
  • After the transition, return to the deck’s stronger long-fight engine once the rapidly scaling first phase is gone.
  • Keep one dense defensive answer or enough HP for the Ringing Stomp rather than relying on several separate defensive actions.
Watch for
  • Building an almost pure Doom deck and discovering that the Boss never leaves the dangerous first phase quickly enough.
  • Overcorrecting by abandoning Doom entirely instead of simply adding enough direct damage to trigger the transition.
Failure Analysis

Common Ceremonial Beast Mistakes

These are the decisions that can make a deck look strong on paper but still fail this specific fight.

01

Trying to block Phase 1 forever

You treat repeated Plow turns like an ordinary defensive cycle and prioritize perfect Block over damage.

Why it fails

Plow gains Strength every turn. Even if one current attack is fully blocked, the next attack becomes harder while the Boss remains above the phase threshold.

Better decision

Build enough defense to survive, then push damage. Reaching 160 HP and triggering the Stun is the real way to stabilize the fight.

02

Ignoring the 160-HP threshold

You play turns by generic damage efficiency without tracking how close Ceremonial Beast is to changing phase.

Why it fails

Crossing the threshold one turn earlier can remove an entire strengthened Plow from the fight and give you a Stun turn. That is much more valuable than the same damage dealt one turn later.

Better decision

Track 160 explicitly and use burst, Vulnerable, or potions when they change the phase timing.

03

Saving several small Blocks for Ringing

You enter the Stomp turn with enough total Block cards in hand but no single card that solves the attack.

Why it fails

Ringing restricts card plays, so the theoretical total Block across several cards is not available.

Better decision

Prepare one dense card such as Blood Wall or Leg Sweep, another single-card mitigation effect, or enough HP to take the hit.

04

Using Beast Cry as unlimited setup time

Because Beast Cry itself deals no damage, you spend the whole turn on optional scaling and ignore the next turn.

Why it fails

Beast Cry is setting up Ringing. The following Stomp is specifically dangerous because your available actions are constrained.

Better decision

Use Beast Cry for setup only after confirming the one-card answer for Stomp is already available or the HP buffer safely covers it.

05

Entering Ringing below the survival threshold

You allow HP to drop too low during Phase 1 because the second phase is generally described as easier.

Why it fails

The first Ringing Stomp still deals 17 on Ascension. If the one-card defensive draw fails, low HP removes the fallback of simply taking the attack.

Better decision

Preserve enough HP during the damage race that the first constrained attack is not automatically lethal.

06

Relying only on Doom with Necrobinder

You assume a strong Doom engine will naturally solve Ceremonial Beast the same way it solves other high-HP targets.

Why it fails

Doom does not trigger the required phase change by itself, leaving the deck exposed to repeated 20-damage Plows and accumulating Strength.

Better decision

Keep the Doom engine but add enough direct physical damage to force the 160-HP transition quickly.

07

Saving an offensive potion past the phase race

You keep a Fire, Attack, Vulnerable, or similar offensive potion because you want maximum value later in the fight.

Why it fails

The hardest section is Phase 1. If the potion crosses 160 one turn earlier, it also prevents another strengthened Plow and creates the Stun transition.

Better decision

Spend the potion when it materially accelerates the phase change. That avoided turn is often the highest-value use in the entire encounter.

Entity Relationships

Appears In

1 encounter

Ceremonial Beast

Boss
Act 1 - Overgrowth →
Game ID: CEREMONIAL_BEAST Data version: v0.107.1 · Main Type: Boss