Here is the full list of all 20 Arcade Game Series: PAC-MAN achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
Eat the Key that appears after eating a set number of Pac-Dots after Round 13!
Clear round 17!
Clear round 13!
Eat the Bell that appears after eating a set number of Pac-Dots in Round 11 or 12!
Eat the Galboss that appears after eating a set number of Pac-Dots in Round 9 or 10!
Clear round 9!
Eat the Melon that appears after eating a set number of Pac-Dots in Round 7 or 8!
Eat all 5 fruits (Cherry, Strawberry, Orange, Apple, Melon) in one playthrough!
Eat all four ghosts in succession four times in a single round!
Eat all four ghosts in succession three times in a single round!
Clear 3 Rounds in a row without eating a single ghost and without losing a life!
Eat 2 fruits and all four ghosts in succession four times in a single round!
Clear round 5!
Eat the Apple that appears after eating a set number of Pac-Dots in Round 5 or 6!
Eat all four ghosts in succession twice in a single round!
Eat the Cherry that appears after eating a set number of Pac-Dots in Round 1!
Eat the Orange that appears after eating a set number of Pac-Dots in Round 3 or 4!
Clear round 2!
Eat the Strawberry that appears after eating a set number of Pac-Dots in Round 2!
Eat all ghosts in succession after eating a Power Pellet!