How to Beat Aeonglass in Slay The Spire 2

If you’re a big fan of Slay the Spire 2 and have been trying out the beta version, you’ve probably noticed that one character seems to be missing.

The Doormaker, whether you liked fighting him or not, has been temporarily removed from the game. He was originally too easy, then became too difficult after some changes. Ultimately, the developers decided it was simpler to just replace him with a different boss.

Meet Aeonglass, a boss with a lot of health but relatively simple attacks. This might have been a good change of pace! We’ll likely see Doormaker again when the next update to Act 3 comes out, but for now, let’s focus on how to defeat Aeonglass.

Encounter Mechanics

Stats and Moves

If you found the Doormaker challenging, you’ll find this boss much easier. Here’s a look at Aeonglass’s basic stats:

Base Stats	Description
HP (535)	While this is a pretty large health pool, it’s actually a decent bit less than Doormaker, Test Subject and the Queen, if you factor in extra minions/forms.
Artifact (3)	This is pretty brutal, especially for those decks specialising in heavy debuffs, like Vulnerable, Doom and Poison.
Withering Presence (4)	This is a new mechanic exclusive to Aeonglass. Every 4 non-status cards you play, a Wither card will be placed into your hand.

Aeonglass has a straightforward battle pattern, repeating a sequence of just three moves before starting over. Here’s what those moves are:

On the first turn, Aeonglass will deal 32 damage and inflict a Debuff on the player. This debuff is called Ebb and will reduce your Strength and Dexterity by 3 for the next turn only.
Next, Aeonglass will hit you with a 12×2 attack.
Finally, Aeonglass will block with a 33 damage shield while boosting its strength by 4. At this point, the boss will cycle and return to move order 1.

This enemy gets stronger quickly, gaining a significant strength boost every few turns and dealing a lot of damage. Its 12×2 attack is especially dangerous, increasing from 24 hits to 32. If you’re trying to lower its strength or use abilities like Weak, removing its Artifact is essential.

Containing the Wither

The biggest challenge in this fight isn’t the boss’s attacks, but dealing with the new wither effect.

Okay, so here’s the deal: every time I play four cards, I get this ‘Wither’ card added to my hand. It does this thing where…

Retain. At the end of your turn, if this is in your hand, take 2 damage. Exhaust.

It doesn’t seem like much at first, but it becomes clear how many cards you’re actually playing by the end of Act 3. Many of the strongest decks in Slay the Spire 2 depend on fast card cycling – constantly playing cards that give you energy and let you draw more – to quickly get through your deck and play as many cards as possible.

This boss is designed to stop players who rely on playing a lot of cards each turn, and it heavily penalizes that strategy. It’s similar to the Time Eater from the first Slay the Spire game, which was a difficult matchup for decks like Shiv-Silent or Claw-Defect because those decks depend on playing many cards.

Okay, so I’ve learned the hard way that if I don’t keep track of my cards, I can end up with a ton of Withers piling up by the end of my turn. The really annoying thing is that these Withers cards stick around – they have this ‘Retain’ ability, which means they don’t go away easily. I can try to ditch them, but honestly, they always seem to come back and mess up my hand later, making it super hard to draw what I actually need.

The most effective strategy is to play cards and wear them down. Keep in mind this uses 1 energy, which might limit your ability to play stronger cards later. Most importantly, don’t let the Withers accumulate too much power, or you’ll quickly lose the game.

Boss Strategies

Getting Rid of Wither

There are a few strategies you can use when fighting Aeonglass, so it’s best to prepare your deck as soon as you anticipate facing her. This is especially important because of the double boss fight in Act 3, which often includes Aeonglass.

Playing many cards quickly generates a lot of Withers. This isn’t an issue for players who use a strategy focused on playing a large number of cards, like those utilizing cards such as Forgotten Ritual, Second Wind, and Fiend Fire.

Just like with the Defect, you can build a powerful strategy around Wither using cards like Compact, Smokestack, and Flak Cannon. These cards essentially convert status cards into extra power, boosting your attacks the more status effects you apply. Cards such as Overclock and Turbo help you cycle through your deck quickly, generating even more status cards in the process.

If you’re unable to get rid of Withers by defeating them, you can always get rid of them by discarding them with a card, or try using Regent Minion cards to change them.

Slow and Steady

Another option is to focus on powerful, expensive cards, or those that gradually inflict damage.

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Decks that focus on a few strong cards, like those using Stardust, Heavenly Drill, or Eradicate, perform well in this situation because they don’t need to play a lot of different cards to be effective.

Decks that focus on playing powerful, costly cards – like Uproar-Defect, Strength-Ironclad, or Bury-Necromancer – also perform well with this strategy. The key is to remove those Artifact counters quickly so you can apply Vulnerable and maximize its impact.

Strategies focusing on poison and damage over time, often called ‘Poison decks’ or ‘Doom builds’, can also be very effective. Cards like Accelerant, No Escape, and Reaper Form are particularly strong because they start with a small effect but quickly become incredibly powerful as the game goes on.

2026-05-11 15:40