Here is the full list of all 14 Derrick the Deathfin achievements.
Get a gold medal in a speed level
Eat a flock of birds
Complete the American zone
Get a gold medal
Finish level with Derrick in reverse
Finish level in the air with Derrick in reverse
Eat 100 creatures in a level
Collect all the objects in a level
Complete the Asian zone
Complete the African zone
Complete the Arctic zone
Complete all the levels in the game
Collect all the objects in the game
Get gold medals in all possible levels