Here is the full list of all 21 Bit Heroes achievements.
Collect 30 Quest Stars
Reach Level 50
Defeat Quirrel
Collect 20 Different Familiars
Defeat Gemm
Collect 15 Quest Stars
Reach Level 20
Make a fusion
Collect 5 Different Familiars
Defeat Lord Cerulean
Collect 5 Quest Stars
Join a Guild
Reach Level 5
Add a friend
Collect 1 Familiar
Reach Level 100
Reach Level 200
Collect 50 Different Familiars
Collect 100 Different Familiars
Defeat Kov'alg
Collect 50 Quest Stars