Here is the full list of all 18 Pac-Man Championship Edition 2 achievements worth 1,000 gamerscore.
Clear area 1 in TUTORIAL!
Clear area 2 in TUTORIAL!
Clear area 1-11 in ADVENTURE!
Clear area 3-11 in ADVENTURE!
Clear area 5-11 in ADVENTURE!
Clear area 6-15 in ADVENTURE!
Obtain Rank C or higher in SCORE ATTACK > SINGLE TRAIN.
Obtain Rank B or higher in SCORE ATTACK > SINGLE TRAIN.
Obtain Rank A or higher in SCORE ATTACK > SINGLE TRAIN.
Obtain Rank S in SCORE ATTACK > SINGLE TRAIN.
Obtain Rank C or higher in SCORE ATTACK > REGULAR.
Obtain Rank B or higher in SCORE ATTACK > REGULAR.
Obtain Rank A or higher in SCORE ATTACK > REGULAR.
Obtain Rank S in SCORE ATTACK > REGULAR.
Obtain Rank C or higher in SCORE ATTACK > EXTREME.
Obtain Rank B or higher in SCORE ATTACK > EXTREME.
Obtain Rank A or higher in SCORE ATTACK > EXTREME.
Obtain Rank S in SCORE ATTACK > EXTREME.