Complete the following tasks to unlock the corresponding achievement. To view your achievements and stats in Steam, select "Community", then "My profile", then "View all my games", then the game and view stats.

Achievement	How to unlock
Ghost ship boss	Player has beaten the Ghost ship boss in story mode.
Gold retriever	Player has destroyed 20 enemy ships carrying gold, and picked up the gold box left behind..
Homing magnet	Player has been hit by a homing dolphin 10 times.
Kraken Again	Player has beaten the second Kraken in story mode.
Kraken	Player has beaten the first Kraken in story mode..
Misplacement	Player has ran into own mines 10 times.
Mr. Jones	Player has beaten Mr. Jones in story mode.
Nightmare	Player has unlocked the nightmare difficulty level.
Perfectionist	Complete any level without losing any gold from chest.
Skeleton Boss	Player has beaten the Skeleton boss in story mode.