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