CheatCodes.com has the complete list of all Sonic The Hedgehog 4: Episode I Achievements and Gamerscores for X360, including all secret Achievements. All official X360 achievements for Sonic The Hedgehog 4: Episode I as of Wednesday April 1, 2015 are shown below, or you can print out our Printable Achievements Checklist that shows all Sonic The Hedgehog 4: Episode I Achievements and Gamerscores in a simple quick-reference format.
Clear SPLASH HILL ZONE, ACT 1.
Defeat a boss for the first time.
Acquire a Chaos Emerald.
Defeat 1,000 enemies.
Clear all Acts as Super Sonic.
Defeat the final boss and view the ending.
Upload your recorded scores and clear times for all stages.
Collect all the Rings in 'Special Stage 1' and Clear the stage.
Build up 99 or more extra lives.
Acquire all seven Chaos Emeralds.
Clear SPLASH HILL ZONE ACT 1 in less than a minute.
Clear the E.G.G. STATION ZONE without taking any damage.