Here is the full list of all 32 Stirring Abyss achievements.
Earn 20,000 score on Endless Mode.
Deal 150 damage with one critical attack.
Defeat the Captain Ascendant.
Detonate the Soviet nuclear bomb.
Complete the game on Hard difficulty.
Use the Profane Chapel to resurrect a dead diver.
Unlock one of the top-level nodes on the Biological track of the Enigma Board.
Defeat the Gatekeeper.
Kill 500 enemies.
Have a single diver undergo four Mutations.
Recover the arming code for the Soviet nuclear bomb.
Inspect a dead Soviet Diver.
Uncover 1,000 Clues.
Defeat the First to Hunger.
Unlock one of the top-level nodes on the Eldritch track of the Enigma Board.
Inspect a dead Stalking Tentacle.
Kill five or more enemies in a single turn.
Kill one of your divers with friendly fire.
Inspect a dead Voidspawn.
Pump every section of the Salem.
Unlock one of the top-level nodes on the Mechanical track of the Enigma Board.
Inspect a dead Harvester.
Inspect a dead Fathom Seer.
Deal 250 damage to enemies in a single turn.
Inspect a dead Infected Pod.
Mutate one of your divers.
Have an enemy kill another enemy.
Inspect a dead Vessel.
Inspect a dead Murkfiend.
Inspect a dead Spineskulker.
Inspect a dead Burst Pod.
Inspect a dead Scyphozoa.