Here is the full list of all 12 Pac-Man Museum achievements worth 400 gamerscore.
Earn Beginner's Graduation stamp in every game.
Earn 30th Anniversary stamp in every game.
Earn Master stamp in every game.
Earn all Ghost Eater and Ghost Hunter stamps.
Total play time reached 10 hrs.
Earn 10 stamps.
Collect all trinkets.
Earn 72 stamps.
Collect all figures.
Get all pals.
Unlock Pac, Cylindria, and Spiral.
Play 9 different games.