Here is the full list of all 12 Sonic The Hedgehog 4: Episode II achievements worth 200 gamerscore.
Clear SYLVANIA CASTLE ZONE, Act 1.
Activate the Rolling Combo with Sonic and Tails.
Defeat Metal Sonic in SKY FORTRESS ZONE, Act 1.
Defeat all bosses as Super Sonic.
Defeat the final foe and watch the ending.
Upload a Multiplayer score or time.
Play as Tails 50 times.
Beat Special Stage 1 after collecting every Ring.
Clear all stages without returning to the World Map.
Collect all seven Chaos Emeralds.
Clear SYLVANIA CASTLE ZONE, Act 1 in one minute or less.
Defeat the final foe after collecting every Red Star Ring.