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