How to Beat Aeonglass in Slay The Spire 2

If you’re an avid Slay the Spire 2 fan, like me, and have been dabbling in the public beta branch of this excellent Deck-building Roguelike, you’ll know that we seem to be missing a familiar face.

The Doormaker, love him or hate him, has been banished to the shadow realm, or rather, shoved into some box at the back of Mega Crit's closet for a major rework somewhere down the line. At first, this Act 3 boss was a pushover, but with a bit of rework, it became too punishing. Now, it seems it was actually easier to simply replace the Doormaker completely.

Say hello to the Aeonglass, a boss with a massive amount of HP and decidedly easier mechanics. Though perhaps this was for the best. I’m sure we will see Doormaker again, perhaps when the 2nd variant of Act 3 releases, a little later on. But for now, let’s take a look at this brand-new boss, and just how to take it down!

Encounter Mechanics

Stats and Moves

If you thought Doormaker was a bit too complicated, well, this boss is far simpler in comparison. Here’s a breakdown of the passive stats held by Aeonglass:

In terms of moves, Aeonglass has a very simple turn rotation, with only 3 moves before cycling back to the first. These movies are as follows:

1. 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.
2. Next, Aeonglass will hit you with a 12x2 attack.
3. 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 boss scales pretty fast, with that 4 extra strength every 3 turns, dealing some serious damage. This is particularly problematic with the 12x2 attack, which goes from a 24-hit to a 32-hit. For any build looking to reduce Aeonglass’ Strength or using something like Weak, getting rid of that Artifact is crucial.

Containing the Wither

So the main difficulty of this fight isn’t actually the boss itself, but managing the new wither mechanic.

Every single time you play 4 cards, you will get a wither status card added to your hand. It has the following effect:

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

This doesn’t seem that scary at first, until you realise just how many cards you end up playing in late-stage Act 3. Some of the most powerful Slay the Spire 2 decks rely on heavy card cycling, continuously playing energy-granting cards and draw cards, to cycle through the deck and play as many cards as possible.

This boss specifically counters this kind of play style, punishing you for playing too many cards. In this way, the boss is kind of like the Time Eater from Slay the Spire 1. Decks like Shiv-Silent or Claw-Defects hated running up against that boss.

If you aren’t counting your cards as you’re playing them, you can easily end up with 3–4 Withers at the end of a turn. And worst of all, these status cards have Retain, so if you don’t get rid of them, they will stay in your hand and keep dealing damage to you every turn. You can try to discard them, but of course, they will come back and brick your hand later on.

Boss Strategies

Getting Rid of Wither

So there are a couple of ways that you can play against Aeonglass, and it’s helpful to start building these kinds of decks as soon as you know you’re going to be fighting this boss. Or in Ascension 10, assume you will be against Aeonlass due to the double Act 3 boss.

So, if you want to play a bunch of cards, you will accumulate lots of Withers. This isn’t really a problem for the Ironclad, whose most powerful deck revolves around exhausting a huge amount of cards with stuff like Forgotten Ritual, Second Wind and Fiend Fire.

Similarly with the Defect, you can build around Wither by picking up cards like Compact, Smokestack and Flak Cannon. These cards end up turning status cards into literal fuel, making your attacks more powerful the more status cards you have. You also have a lot of cycle here with cards like Overclock and Turbo, which in turn generate more status cards.

If you can’t exhaust the Withers, you can always discard them with Silent, or try to transform them with the Regent Minion cards.

Slow and Steady

Alternatively, you could also adopt an approach that uses strong high-cost cards or cards that deal incremental damage over time.

For example, decks that use a lot of X-cards like Stardust and Heavenly Drill with Regent, or Eradicate with Necrobinder, are great here, as they rely on a single powerful card instead of playing many.

In a similar manner, decks that like to play big expensive cards, like the Uproar-Defect deck, Strength-Ironclad, or even Bury-Necromancer, work well here too. Just try to get rid of the Artifact counters as quickly as possible so you can lay down Vulnerable for maximum effect.

Finally, Poison decks and Doom builds also work, as the majority of the damage comes from the build-up over time. Cards like Accelerant, No Escape, and Reaper Form are brilliant because they start slow but scale up to ridiculously high numbers quickly.