Boss Guide

Slay the Spire 2 Aeonglass Boss Guide

Aeonglass is the current Glory boss read: 512 HP, 535 HP on the tougher band, Withering Presence on the player, and a strict Ebb -> Eye Lasers -> Increasing Intensity loop.

The fight is not about guessing a random phase. Aeonglass opens by putting Withering Presence on the player and Artifact 3 on itself, then repeats three turns in order. Count the Wither timer, spend non-Status cards with intent, and do not let the block-and-Strength turn make the next pass bigger than your deck can answer.

Boss HP512 / 535OpeningWithering Presence + Artifact 3Ebb26 / 32 + Ebb 3Eye Lasers11x2 / 12x2Intensity33 Block + 3 / 4 StrengthLoopEbb -> Eye Lasers -> Intensity
Aeonglass boss icon

Core Read

The fight is readable once the hand timer stops being treated like flavor text.

The clean read is simple: Aeonglass pressures your hand first, your stats second, and your damage clock last.

Withering Presence turns every fourth non-Status card into a Wither problem. That means card count matters as much as Energy count.

Increasing Intensity is not a free turn. The 33 Block slows your kill, and the Strength gain makes the next attack cycle more expensive to survive.

Move Loop

Read this top to bottom. There is no reason to carry the wrong Act 3 boss script into the room.

Withering Presence power icon

Opening Setup

0

Every 4 non-Status cards you play, add a Wither to your Hand.

The boss also starts with Artifact 3. Strip Artifact before relying on debuffs, and watch the non-Status count before playing low-impact filler.

Ebb power icon

Ebb

26 / 32

Applies Ebb 3, lowering Strength and Dexterity for the turn.

This is the single-hit pressure turn. Weakening your Strength and Dexterity on the same turn makes both blocking and counterpressure worse.

Aeonglass boss icon

Eye Lasers

11x2 / 12x2

Two-hit attack with no setup break.

Multi-hit mitigation is worth more here than on Ebb. This is also the turn where bad Wither timing often forces awkward card spending.

Strength power icon

Increasing Intensity

33 Block + 3 / 4 Strength

Gains Block and growing Strength, then returns to Ebb.

The first Strength gain is 3, or 4 on the harder attack band. The fight increments from there, so slow decks must treat this as a clock.

Rules That Matter

These are the details that change sequencing, not trivia to memorize after the fight.

Withering Presence counts non-Status cards

Status cards do not advance the counter. Attacks, Skills, and Powers do, so a cheap setup turn can still hand you the next Wither if it spends four real cards.

Wither punishes ending the turn with it in hand

Wither is a Status card with Retain and Exhaust. If it remains in hand at turn end, it deals 2 damage to you. The practical answer is usually to spend it before the hand clogs.

Artifact changes the first debuff plan

Aeonglass starts with Artifact 3. Vulnerable, Weak, Poison, Doom-adjacent setup, and other debuff plans need to account for those first three negations.

Increasing Intensity scales the next loop

The block turn is not passive. It adds Strength, then the next Ebb and Eye Lasers cycle becomes harder to block cleanly.

How To Play It

The useful plan is short: manage the fourth non-Status card, clear Artifact before trusting debuffs, and do not let the block turn stretch the fight for free.

Keep low-impact cards out of the fourth slot

If the fourth non-Status card is a weak setup card, you still pay the Wither tax. Spend the fourth card when it advances damage, block, or a needed debuff clear.

Strip Artifact before trusting debuffs

The first three debuffs do not stick. Plan the first cycle around direct output, artifact removal, or debuff volume instead of assuming one premium debuff solves the turn.

Block Ebb like a stat-loss turn

Ebb is not only damage. Losing Strength and Dexterity for the turn can make ordinary answers underperform, especially if your block line depends on Dexterity.

Treat the Block turn as a deadline

Increasing Intensity buys Aeonglass time and raises future damage. If your deck cannot punch through the 33 Block, the next cycle is already worse.

Common Mistakes

Most losses here come from ignoring one counter and then calling the fight random.

Counting only HP and ignoring the Wither timer. That is how strong decks lose to hand pressure instead of raw damage.

Spending four non-Status cards because they are cheap. Cheap still advances Withering Presence.

Saving all mitigation for Eye Lasers while Ebb quietly cuts the stats that make your next response work.

Treating Increasing Intensity as a rest turn. It is the boss buying time and raising the next damage pass.

Related Pages

Open the page that answers the next question instead of forcing one guide to do every job.

FAQ

Short answers for the lines players are most likely to miscount.

What is the current Aeonglass move order?

After the opening setup, Aeonglass loops Ebb, then Eye Lasers, then Increasing Intensity, and then returns to Ebb.

How much HP does Aeonglass have?

Aeonglass has 512 HP on the base band and 535 HP on the tougher HP band.

What does Withering Presence do?

Every fourth non-Status card you play adds a Wither to your hand. Status cards do not advance that counter.

What does Wither do?

Wither has Retain and Exhaust. At the end of your turn, if it is still in your hand, it deals 2 damage to you.

What does Ebb do?

Ebb lowers your Strength and Dexterity by 3 for the turn, then restores those stats at the end of the player turn.

Why does Increasing Intensity matter if it does no damage?

It gains 33 Block and Strength. That delays your kill and makes the next attack cycle more dangerous.