Here is the full list of all 29 Project Abyss achievements.
Unlock the Attack Submarine.
Discover all friendly sea creatures.
Complete the game.
Defeat the creature.
Enter the deep trench.
Complete area D.
Destroy the Command Centre and open the door.
Defeat a Whale.
Discover all vicious sea creatures.
Compelete area C.
Defeat The Tank.
Collect 10,000 pounds.
Find the skeleton.
Complete area B.
Unlock the Defence Submarine.
Defeat The Ripper.
Collect poison.
Unlock the Survival Submarine.
Complete area A.
Destroy The Swarm.
Collect a great chest.
Be underwater for 10 days.
Complete the tutorial.
Refill the submarine with less than 10 fuel left.
Watch a sun-rise.
Deploy a drone to help you collect loot.
Return to the submarine with less than 10 oxygen left.
Leave the submarine.
Chain hook the submarine.