Slay the Spire 2 Ascension Guide: Tips for Climbing Every Level

What Is Ascension?

Ascension is Slay the Spire 2’s difficulty system. After winning a run with any character, you unlock Ascension 1 for that character. Each Ascension level adds a permanent modifier that stacks on top of all previous ones. By Ascension 10, you’re dealing with tougher elites, fewer healing options, worse card rewards, and nastier enemies all at once.

There are 20 Ascension levels, tracked independently per character. Progress with Ironclad doesn’t unlock anything for Silent. You’re climbing five separate ladders.

Ascension Levels Explained

Levels 1-5: The First Wall

Ascension 1 — Swarming Elites: More elite encounters appear on the map. You’ll run into dangerous fights more often per act, which means more relic opportunities but also more HP spent getting them.

Ascension 2 — Weary Traveler: Rest sites heal 25% of max HP instead of 30%. That 5% difference doesn’t sound like much until you’re choosing between healing and upgrading three times per act. The cumulative HP loss adds up fast.

Ascension 3 — Poverty: You earn 25% less gold from fights. Shops become luxuries, not guarantees. Card removal, relics, potions — you can’t afford everything anymore. Budget carefully.

Ascension 4 — Tight Belt: One fewer potion slot. Potions are your emergency buttons for elite and boss fights. Losing a slot means one fewer safety net when a fight goes sideways.

Ascension 5 — Ascender’s Bane: You start every run with a Curse card in your deck. It’s Eternal, meaning you can’t remove it. Your opening draws are immediately worse, and it stays in your deck forever. This is where most players hit their first real wall.

Levels 6-10: Real Difficulty Starts Here

Ascension 6 — Inflation: Card removal starts at 100 gold (up from 75) and increases by 50 per removal instead of 25. Trimming your deck gets expensive fast, which compounds with A3’s gold penalty. Suddenly a second card removal costs 150 gold — that’s a Rare card you’re not buying.

Ascension 7 — Scarcity: Rare and upgraded cards appear half as often in card rewards after fights. Your card pool is weaker on average. You can’t count on finding your build’s payoff card — plan around commons and uncommons instead.

Ascension 8 — Fortified Foes: All enemies have more HP. Fights last longer, which means more total damage taken per encounter. Inefficient damage cards that were fine at lower Ascension can’t keep pace anymore.

Ascension 9 — Empowered Foes: All enemies deal more damage. Combined with A8, every fight is both longer and more punishing per turn. The Block thresholds that used to cover a full enemy turn don’t cut it anymore.

Ascension 10 — Double Boss + Ascender’s Bane: Act 3 ends with two boss fights back to back, and you start with a second Ascender’s Bane (stacking with A5, so you have two permanent Curses). Your deck has to beat two bosses without resting between them, all while cycling through two dead draws every rotation.

Levels 11-20: The Endgame Grind

These levels continue stacking penalties: even less healing, starting with less gold, more Curse cards, and the final boss gains additional phases. Each level past 10 demands near-perfect play and deep knowledge of every encounter in the game. The community is still mapping optimal strategies for A15+ since the game launched recently.

Strategies That Work at High Ascension

Focus on One Character

This is the single best piece of advice for climbing. Deep knowledge of one character’s card pool, relic interactions, and matchups beats shallow familiarity with all five. You’ll learn which cards are traps, which relics enable your best builds, and which boss patterns demand specific answers.

Start with Ironclad. He’s the most forgiving, and Burning Blood compensates for the increased chip damage at higher Ascension levels.

Deck Thinning Is More Important Than Card Adding

At Ascension 0, a 25-card deck works because enemies are soft enough that drawing your best cards sometimes is enough. At Ascension 8+, you need to draw your best cards most turns.

Keep your deck at 15-20 cards. Remove Strikes and Defends at every opportunity. The shop’s card removal (75 gold, escalating by 25 per use) is your most efficient tool. Events that offer free removal are almost always worth taking.

A tight deck draws its win condition every 3-4 turns. A bloated deck might not see it for 6-7 turns. Against Ascension bosses, those extra turns kill you.

Prioritize Relics Over Cards

Relics provide passive value across every combat for the rest of the run. A good relic outperforms a good card because the relic never needs to be drawn.

Fight 2-3 elites per act when your deck can handle them. Elite fights are the primary source of relics. Energy relics are the highest priority — an extra Energy per turn means an extra card played per turn, which compounds across every fight.

Treat HP as a Resource, Not a Score

Spending 10 HP to beat an elite and gain a relic is almost always worth it. Spending 8 HP to skip a rest site and upgrade instead is usually worth it. Your HP isn’t there to stay full — it’s there to be spent strategically.

Ironclad is the best at this because Burning Blood heals 6 HP after every combat. That’s 30-40 free HP per act just from fighting.

Understand Boss Matchups Before Act 1

Each act has a pool of possible bosses. Before picking cards, think about which boss you might face and what your deck needs to beat it.

In the Hive (Act 2), all three bosses punish slow decks. Kaiser Crab has massive combined HP across two targets. Knowledge Demon stacks debuffs. The Insatiable escalates. If your deck can’t deal damage fast, you won’t survive Act 2 at high Ascension.

Build your deck to beat the hardest boss in the pool, and the easier ones take care of themselves.

Character-Specific Ascension Tips

Ironclad

Burning Blood makes Ironclad the most forgiving Ascension climber. You can afford to take more elite fights and rest less. Strength builds stay functional even with common cards because Strength applies to every attack regardless of rarity. At A10+, Offering becomes a must-take because the Energy and draw are worth more than the HP cost.

Silent

Wraith Form carries high-Ascension runs. Two to three turns of Intangible buys time against bosses that would otherwise kill you during setup. Poison builds scale independently of card rarity, which matters when A10 gives you worse card rewards. Sly builds work but require precise hand management — mistakes are less forgivable at high Ascension.

Defect

Focus scaling determines Defect’s Ascension ceiling. Without Defragment or Biased Cognition, orbs generate too little value to keep pace with buffed enemies. Frost orbs are your primary defense — prioritize them over Lightning at A7+.

Regent

The hardest Ascension climber. Managing two resources (Energy and Stars) under pressure requires experience. Don’t attempt high Ascension on Regent until you’re comfortable with the Star economy in low-Ascension runs first.

Necrobinder

Doom instant-kill bypasses the bigger HP pools that Ascension gives to enemies. This makes Necrobinder surprisingly effective at high Ascension once you understand the Doom thresholds. The fragility hurts, though — Osty needs to do significant blocking while you stack Doom.

The Mental Game

Ascension climbing is a grind. You’ll lose runs to bad luck, bad draws, and bad boss matchups. Some runs are unwinnable from the first few card offers. That’s part of the design.

What separates A10 players from A20 players isn’t mechanical skill — it’s pattern recognition accumulated over hundreds of runs. Every loss teaches you something. Every failed build shows you where the archetype breaks. The data compounds.

Don’t tilt after losses. Take what you learned, queue the next run, and apply it.