Here is the full list of all 30 Mooch achievements.
Finish game on easy mode
Finish game on normal mode
Finish game on hard mode
Beat The Eye
Beat Giganto
Make a leap of faith
Beat Mayestro
Activate Big G
Trigger an alarm
Make an enemy to fall down
Make enemy to open door
Beat The Mine
Shoot enemy with a tank
Make a Drill drill way for you
Finish Bullethell level
Beat 503
Beat Egdecrusher
Escape from a boulder
Get into a follower
Find teleport sequence
Find secret cave
Smash enemy
Beat Hammerstrike
Finish pac-level
Beat The Worm
Use a teleporter
Beat Spider bot
Pass the first enemy
Fall into a hole
Collect first part of Tulas soul