Goodbye Doormaker: Aeonglass Takes Over Act 4

~10 min read · How the biggest boss change in STS2 history reshapes your runs

📅 Published: June 22, 2026 · v0.107.1 (Jun 19) — Doormaker removed, Aeonglass promoted

The End of an Era

With v0.107.1 Major Update #2, Mega Crit made the boldest boss change in STS2 history: Doormaker has been deleted from the game, and Aeonglass is now the permanent Act 4 boss. This isn't a test, it's not behind a flag — Aeonglass is the new gatekeeper between you and victory. Every deck you built for Doormaker needs to be re-evaluated.

Why Now? Mega Crit has been iterating on Aeonglass since v0.105.0 (Experimental Branch). After two balance passes and community feedback, they've concluded that Aeonglass offers a richer, more strategic boss fight than Doormaker ever did. The data backs this: Doormaker's win rate variance was extreme (35% burst vs 5% anything else), while Aeonglass tests a broader set of deck skills.

Doormaker vs. Aeonglass: What Actually Changed

❌ Old: Doormaker

Burst-damage check: Kill doors before they escalate
Scaling irrelevant — burst or die
Block hardly matters — doors don't attack you
Any deck with 2–3 big attacks could clear it
Win rate: 30–40% (but 80%+ for burst decks)

✅ New: Aeonglass

Sustained boss fight: Multi-phase, 5–8 turn fight
Both damage AND block required
Wither mechanic: Reduces max HP each turn
Scaling damage, Weak, and cleanse effects matter
Win rate: 25–40% (varies by character, much more balanced)

What Strategies Are Now Dead

These Doormaker-era strategies no longer work for Act 4:

1. "Draft 3 big attacks and skip block" — Aeonglass attacks every turn. No block = death by turn 4.
2. "Rely on one-shot burst" — Aeonglass has multiple phases with HP thresholds. You can't skip mechanics with damage.
3. "Ignore scaling, play aggro" — Wither punishes long fights, but you still need scaling to close before Wither kills you.
4. "Skip Weak/Cleanse cards" — Weak is mandatory against Aeonglass's multi-hit pattern. Cleanse effects (or ways to out-scale Wither) are premium.

Character-by-Character: Aeonglass Matchup Guide

Silent — Best Matchup (36.3% WR overall)

Sly Discard was built for this fight. Infinite energy + scaling Sly Strikes outpace Wither naturally. Leg Sweep and Scare provide Weak uptime. The draw engine finds answers on demand. No build adjustment needed — if your Silent deck is good, it beats Aeonglass.

Necrobinder — Strong (34.0% WR)

Summons provide chump-blockers against targeted attacks. Sic 'Em scaling keeps pace with Wither. Debilitate's doubled Weak/Vulnerable is premium even with the duration nerf — save it for the final phase. Key tip: Aim for 4+ summons by turn 3. They absorb damage while you scale.

Ironclad — Struggles Most (32.6% WR)

The Block Ramp archetype's biggest weakness is Wither — building 999 block doesn't help when your max HP is 35. The Exhaust archetype performs better: cycle to key block cards faster, end fights in 5–6 turns. Build shift: Swap Barricade for more damage. Entrench is still good, but don't overcommit to block.

Ironclad Aeonglass Checklist: Bring 2+ damage scaling cards (Spot Weakness + Limit Break or Demon Form). Weak application matters more than you think — consider Shockwave. Healing relics (Meat on the Bone, Burning Blood) offset Wither HP loss. Don't draft Barricade unless you have Calipers.

Defect — Improved (32.3% WR)

Plasma cycling generates energy to play around Wither. Focus scaling (Defragment) provides block independent of max HP. The RNG rework makes orb generation sequences more predictable, which matters in a multi-phase fight. Key tip: Frost orbs are better than Lightning against Aeonglass — the block matters more than the ping.

Regent — New Hope (31.6% WR)

This is where Ritual builds shine. Ritual scaling ignores Wither's max HP reduction — your damage comes from Ritual stacks, not max HP. Sly stacking still works but is less consistent. Build shift: If you see Aeonglass coming, pivot to Ritual. Ritual Potion (0-cost) + Ritual Dagger (12 base, doubled Ritual bonus) + Prophesize (draw 3) is your core package.

Aeonglass Fight Phases & Turn-by-Turn

Phase	HP Threshold	Pattern	Response
1 — Gathering Storm	100% → 70%	Single attacks (10–15 dmg), applies 1 Wither/turn	Play scaling cards, minimal block (8–12 per turn)
2 — Withering Gaze	70% → 40%	Multi-hit (4×5 + Wither), applies 2 Wither/turn	Pop Weak now. Block 20+ per turn. Cleanse if you have it.
3 — Desperation	40% → 0%	Big single hit (25–35 dmg) + Wither burst (3 stacks)	All-in damage. Potion usage. This is a race — Wither will kill you in 2–3 turns.

Aeonglass Phase Transition Rule: When Aeonglass crosses a HP threshold, it finishes its current intent before switching phases. You can use this to set up — trigger the 70% threshold after a blockable attack, not before a big hit.

Updated Build Tier List for Act 4

Tier	Build	Character	Aeonglass Matchup
S	Sly Discard	Silent	Excellent — draw + scaling + Weak = perfect counter
S	Sic 'Em Summon	Necrobinder	Excellent — summons tank hits, scaling outpaces Wither
A	Ritual Synergy	Regent	Very Good — Ritual ignores Wither, slow but reliable
A	Plasma Cycling	Defect	Good — energy surplus, Frost orbs provide consistent block
B+	Exhaust Synergy	Ironclad	Average — cycles fast enough to close before Wither kills
B	Sly Stacking	Regent	Below Average — Sly doesn't out-scale Wither
B	Block Ramp	Ironclad	Poor — Wither counters block-stacking; need damage pivot

How to Transition Your Strategy

Stop drafting for burst. Your Act 1–3 plan shouldn't be "get big attacks for Doormaker" anymore.
Draft Weak. Every character should have at least 1 Weak source by Act 3. It's the single best debuff against Aeonglass.
Value scaling more. Aeonglass is a 5–8 turn fight. Cards that get stronger over the course of the fight (Demon Form, Noxious Fumes, Focus, Ritual stacks) are now premium.
Save a potion for Phase 3. The Desperation phase is a damage race. A Strength/Dexterity/Focus potion can be the difference between winning and losing to the Wither burst.
Don't overcommit to block. 999 block doesn't save you from Wither. Aim for 20–40 block per turn, invest the rest in damage scaling.

📋 More Act 4 resources:

Full Aeonglass Boss Guide · Boss Database · v0.107.1 Full Analysis · Top 5 Builds