Here is the full list of all 12 Sonic The Hedgehog 4: Episode I achievements worth 200 gamerscore.
Upload your recorded scores and clear times for all stages.
Clear all Acts as Super Sonic.
Acquire all seven Chaos Emeralds.
Clear the E.G.G. STATION ZONE without taking any damage.
Defeat 1,000 enemies.
Defeat the final boss and view the ending.
Build up 99 or more extra lives.
Collect all the Rings in 'Special Stage 1' and Clear the stage.
Clear SPLASH HILL ZONE ACT 1 in less than a minute.
Defeat a boss for the first time.
Acquire a Chaos Emerald.
Clear SPLASH HILL ZONE, ACT 1.