Here is the full list of all 25 Pac-Man and the Ghostly Adventures achievements worth 1,000 gamerscore.
Defeat 100 enemies as Metal Pac.
Complete all levels of the Pacerchini arcade mini-game.
Complete all levels of the Lemon Rocket arcade mini-game.
Complete all levels of the Cherry Copter arcade mini-game.
Complete all levels of the Pineapple Tank arcade mini-game.
Collect at least one Arcade Token in every level.
Complete the final level of the game.
Complete all bonus levels.
Unlock Chapter 6.
Increase Pac's total lives to 50 or more.
Increase Pac's maximum Health to 6.
Unlock Chapter 5.
Defeat 300 Blue (Scared) Ghosts.
Defeat 100 enemies as Fire Pac.
Unlock Chapter 4.
Collect enough Globe Energy orbs to unlock the Temple of Mystery.
Collect enough Globe Energy orbs to unlock the Temple of Ice.
Unlock Chapter 3.
Defeat 100 enemies as Granite Ball Pac.
Defeat 100 enemies as Chameleon Pac.
Chomp 50 recycling bins over the course of the game.
Collect enough Globe Energy orbs to unlock the Temple of Slime.
Unlock Chapter 2.
Complete an entire level without losing a life.
Defeat 100 enemies as Ice Pac.