Here is the full list of all 13 Dickland achievements.
No fluff, no feather. (Good luck)
Dark as ass by ass!
Well, thickets!
Selfishness!
Defeat the first boss!
Defeat the second boss!
Complete the level in the clouds.
Complete the first underwater level.
And sat down and ate!
Collect over 90% of diamonds in all levels!
Complete over 90% of the levels with 3 hearts!
Collect in total complexity ??? diamonds!
Alone is good, but two are more fun!