Here is the full list of all 21 Duck Souls achievements.
You found the hidden easter egg!
You unlocked the sunglass!
You unlocked the skull!
You unlocked the ushanka!
You unlocked the white fedora!
You unlocked the black power!
You unlocked the space helmet!
You unlocked the cat hat!
You unlocked the galea!
You unlocked the crown!
You unlocked the witch hat!
You unlocked the christmas hat!
You unlocked the toque!
You unlocked the irish hat!
You unlocked the viking helmet!
You unlocked the miner hat!
You unlocked the propeller hat!
You unlocked the fedora!
You unlocked the rabit ears!
You unlocked the topper hat!
You unlocked the bandana!