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