Here is the full list of all 25 Pac-Man and the Ghostly Adventures 2 achievements worth 1,000 gamerscore.
Attract and chomp 100 enemies using Metal Pac's magnet tongue.
Win a Gold Medal on every level.
Beat the high score on all Netherworld (Chapter 5) levels.
Get the Pac Prize score bonus at least once on every level.
Successfully complete all Betrayus Challenges at least once.
Visit every Arcade Zone in the game.
Beat the high score on all Prehistoric Pac-World (Chapter 4) levels.
Freeze 100 enemies with Ice Pac's Special attack.
Beat the high score on all Space (Chapter 3) levels.
Stun 100 enemies with Fire Pac's Special attack.
Stun 100 enemies with Rubber Pac's Special attack.
Complete the Lemon Rocket level without losing a life.
Beat the high score on all Paclantis (Chapter 2) levels.
Defeat 5 Stone Monsters as Granite Ball Pac.
Complete the Tutorial and all of the Berry Challenges.
Beat the high score on all Pacopolis (Chapter 1) levels.
Complete any Spiral Cherry Copter level without losing a life.
Defeat 200 Blue (Scared) Ghosts.
Complete any Cyli Hover Board level without losing a life.
Get the number of Pac's Lives up to 50.
Talk to each of Pac's friends between levels at least once.
Read the bios for each of Pac's friends between levels.
End a level with six Health (Hearts).
Grab 200 Pac Pellets in a single level.
Chomp every container in any level.