Here is the full list of all 14 Pikuniku achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Make an artistic statement
Finish a coop level in less than 3 minutes
Found every trophy
999
Kick Mr. Sunshine into space
Found every insect
Get some arms
100% against the dance king
Escaped from Toastopia
Kick your friends 50 times during a single level
Collected 70 coins
No respect for Sam's potteries
3 baskick loss in a row
3 baskick wins in a row