Full list of all 46 Slay the Spire achievements. It takes around 60-80 hours to unlock all of the achievements in the base game on Windows.
The base game contains 26 achievements, and there are 8 DLC packs containing 20 achievements.
Defeat a boss in a single turn.
Win a battle with 1 HP remaining.
Have 3 or fewer cards in hand, draw, and discard pile combined.
Play 10 Shivs in a single turn.
Exhaust 20 cards in a single combat.
Have 50 or more Strength during combat.
Have 999 Block during combat.
Have 99 or more Block during combat.
Play 25 cards in a single turn.
Have 10 or more buffs during combat.
Win a combat without playing an Attack.
Apply 99 or more Poison on a single enemy.
Defeated the Time Eater.
Have 9 Energy during a single combat.
Defeat 3 enemies with Poison in a single combat.
Defeat a boss without taking any damage.
Defeated Hexaghost.
Defeated the Slime Boss.
Defeated the Bronze Automaton.
Defeated the Collector.
Defeated the Awakened One.
Defeated Donu & Deca.
Beat the game with the Ironclad.
Beat the game with the Silent.
Defeated the Champ.
Defeated the Guardian.
Obtain all other Achievements.
Beat the game in under 20 minutes.
Beat the game with a single relic.
Beat the game with a 5 card deck or smaller.
Complete Ascension Level 10.
Finish Donu with a Feed.
Unlock Ascension mode.
Have 25 or more Focus during combat.
Beat the game with a deck of only common cards.
Beat the game with the Defect.
Channel 9 Plasma in a single turn.
Win a Daily Climb.
Defeat the Transient before it fades away.
Complete Ascension Level 20.
Complete the Ending with the Watcher.
Beat the game with the Watcher.