๐Ÿ’€ How to Beat A10 with Every Character: Ultimate Ascension Clear Guide

๐Ÿ“… Updated Jun 3, 2026 ยท โฑ๏ธ 17 min read ยท ๐Ÿท๏ธ A10 Guide v0.106.1

A10 (Ascension 10) is the highest difficulty in STS2 Early Access. All 10 negative modifiers stack: tougher enemies, fewer potion slots, less gold, deadlier elites, and punishing boss patterns. ~17% of A10 runs succeed. This guide breaks down how to clear A10 with every character โ€” what changes, what to prioritize, and which builds actually work at max difficulty.

A10 Modifiers Summary (What Changes from A0)

AscensionModifierImpact
A1More elites spawnMore relics, more risk
A2Normal enemies are deadlierHallway fights cost more HP
A3Elites are deadlierElite fights significantly harder
A4Bosses are deadlierAct bosses have new attack patterns
A5Heal less after boss fights75% healing โ†’ 50% at A10
A6Start each run damagedStart at 80% HP
A7Normal enemies are tougher+HP and +damage on all normals
A8Elites are tougherMajor HP/damage scaling on elites
A9Bosses are tougherMajor HP/damage scaling on bosses
A10Less favorable ? eventsHealing events nerfed, bad events more common

10 Universal A10 Tips

  1. Act 1: prioritize front-loaded damage over scaling. A10 Gremlin Nob kills you on turn 3 if you can't deal 85+ damage by then.
  2. Path for 1-2 elites max in Act 1. 3 elites is suicide. You need relics but you need to survive more.
  3. Campfires: upgrade > rest. Resting heals ~20% HP at A10 (nerfed from 30% at A0). An upgraded key card is worth more than 20 HP over 3 fights.
  4. Potions: use them. At A10, your last potion slot is lost. Don't hoard โ€” a Fire Potion used on an elite saves 25 HP.
  5. Skip mediocre cards aggressively. A10 punishes deck bloat. If a card isn't top 25% for your build, skip it.
  6. Gold efficiency matters. With nerfed gold income, every shop visit must count. Remove a Strike or buy a key relic. Don't buy potions at shops.
  7. Know your boss before Act 1 ends. The map shows the Act boss. Prepare specifically: AOE for Slime Boss, block scaling for Guardian.
  8. Heal events are traps at A10. Events that cost HP for a reward at A0 are often correct at A10 too โ€” but the HP cost hurts more. Evaluate carefully.
  9. Boss relic swap is better at A10. The difficulty spike makes the early-game power of a 4th energy more valuable than at lower ascensions.
  10. Mental: treat A10 as a puzzle, not a grind. Every loss teaches a specific lesson. Record why you died and adjust.

Per-Character A10 Strategy

Ironclad โ€” A10 WR: ~17%

Best build: Corruption Exhaust (only consistently viable A10 build for Ironclad). Strength is too slow against A10 elites.
Act 1 plan: Take every Attack card offered in the first 5 floors. You need 5+ Attacks before the first elite. Whirlwind, Uppercut, Clothesline are premium.
Key relic: Burning Blood is your only sustain. Value max HP relics highly. Self-Forming Clay is A10 MVP โ€” blocks multi-hit from elites.
A10-specific: A10 Ironclad cannot afford to rest at campfires. Your deck must be good enough that you upgrade every time. If you're resting more than once, your deck is already behind.

Silent โ€” A10 WR: ~19% (Highest)

Best build: Sly Discard. Poison works as a secondary if you find Catalyst early.
Act 1 plan: Sneaky Strike, Dagger Throw, Eviscerate are A10 Act 1 staples. You need discard synergy to survive elites. Neutralize+ is your best friend.
Key relic: Ring of the Snake's +2 draw is huge at A10 where drawing the right cards matters more. Tough Bandages is S-tier.
A10-specific: Silent has the highest A10 WR because Sly Discard is inherently consistent โ€” it plays many cards per turn and cycles the deck fast. Don't greed for Catalyst if you don't have poison support.

Defect โ€” A10 WR: ~15%

Best build: Frost Wall. Nothing else survives A10 Act 2 elites consistently.
Act 1 plan: This is critical. You MUST find Ball Lightning and Cold Snap before the first elite. Without them, Gremlin Nob is a run-ending fight. Skip if you don't find damage by floor 5.
Key relic: Cracked Core generates 1 Lightning orb. This is weak. Boss relic swap is the highest A10 ROI for Defect.
A10-specific: The A10 Defect run dies in Act 2. The difficulty spike from Act 1 โ†’ Act 2 is the largest for any character. You need Frost setup by the Act 1 boss fight, or you won't survive Act 2 hallway fights.

Necrobinder โ€” A10 WR: ~18%

Best build: Summon army. Doom is bad at A10 due to enemy HP scaling.
Act 1 plan: Skeleton Crew, Grave Call, Bone Wall. Any minion card is premium. Necrobinder's starter deck handles early fights, so you can greed for minion cards.
Key relic: Dead Branch generates minion cards on exhaust. Bottled Flame + key minion card ensures turn-1 setup.
A10-specific: Minion positioning matters at A10. Place tanks (Bone Golem) in front, DPS (Skeleton Archer) in back. Mismanaging minion order = losing 10+ HP per fight.

Regent โ€” A10 WR: ~16%

Best build: Starfall Combo. Sly Control is too slow for A10 enemy scaling.
Act 1 plan: Take Celestial Mark, Stargaze, Intrigue. Any Star/Sly generator. Regent's starter deck is the largest โ€” you'll cycle slower, so every card matters more.
Key relic: Sealed Throne (+2 Stars at start) enables Star build from floor 1. Ancient Scepter is the A10 dream.
A10-specific: Regent's A10 challenge is resource management under pressure. A10 enemies hit harder, so you have fewer turns to set up Stars. Commit to ONE resource path by floor 8 โ€” multi-resource builds die in Act 2.

A10 Boss-Specific Tips

BossA10 ChangeCounter
GuardianEnters defensive mode at 60% HP (was 50%)Burst before 60%, then block through Thorn mode
Slime BossSplits at 60% HP (was 50%), Medium slimes have +HPAOE or controlled burst before the split
HexaghostTurn-2 Inferno deals 6ร—6 (was 4ร—6)Block potion or 30+ block on turn 2
AeonglassSummons 2 Crystals instead of 1, Crystal HP upKill Crystals immediately or out-block the combo
Corrupted HeartBeat of Death: 3 dmg (was 2), HP 880 (was 800)After Image, Frost orbs, or Feel No Pain mandatory
๐ŸŽฏ Key Takeaway: A10 isn't about playing perfectly โ€” it's about making fewer mistakes than your HP bar can absorb. The #1 A10 killer isn't boss fights; it's Act 2 hallway fights. Build your deck to survive Act 2, and the rest follows. Silent (Sly Discard, 19% WR) is the safest first A10 clear.