Here is the full list of all 31 Mumps achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Unlock Level 1
Unlock Level 2
Unlock Level 3
Unlock Level 4
Unlock Level 5
Unlock Level 6
Unlock Level 7
Unlock Level 8
Unlock Level 9
Unlock Level 10
Unlock Level 11
Unlock Level 12
Unlock Level 13
Unlock Level 14
Unlock Level 15
Unlock Level 16
Unlock Level 17
Unlock Level 18
Unlock Level 19
Unlock Level 20
Unlock Level 21
Unlock Level 22
Unlock Level 23
Unlock Level 24
Unlock Level 25
Unlock Level 26
Unlock Level 27
Unlock Level 28
Unlock Level 29
Unlock Level 30
Collect 1 acorn