Sonic The Hedgehog - Extras menu

Play as Shadow The Hedgehog:
Successfully complete Crisis City as Sonic.

Silver The Hedgehog:
Win the Silver The Hedgehog Boss battle as Sonic.

Last Episode:
Complete Sonic's Episode, Silver's Episode, and Shadow's Episode.

Free mode characters:
Complete the indicated task to unlock the corresponding character in Free mode.

Amy Rose: Complete all Soleana mystery missions with an "S" rank.

Blaze the Cat: Complete all Soleana mystery missions.

E-123 Omega: Complete all GUN Commander missions with an "S" rank.

Knuckles the Echidna: Complete all Town Stage missions with an "S" rank.

Miles "Tails" Prower: Complete all Town Stage missions.

Rouge the Bat: Complete all GUN Commander missions.

Unlimited jump:
There is a glitch in the purple gem you can purchase at the market. The purple gem allows you to "change size" in the description, shrinking you down to fit in small areas. However when using the gem for Sonic you are able to jump infinitely. When you press Jump while holding Activate Ge and repeatedly tap A, your character will act as if he wants to do the homing attack. However the game glitches, cancels it out, and allows you to jump as many times as desired while moving in the direction you wish to go. This allows you to get to interesting parts of Soleena or an action stage that you were not meant to access. If you die or find a alternate way to lose the gem it will be "out of stock" for some time.

Achievements:
Complete the following achievements to unlock Xbox Live Gamerscore points.

Sonic Episode - Cleared 30 points: Clear Sonic Episode.

Shadow Episode - Cleared 30 points: Clear Shadow Episode.

Silver Episode - Cleared 30 points: Clear Silver Episode.

One To Reach The End 20 points: End the last hidden story.

Sonic Episode - Completed 40 points: Clear unlocked Sonic difficult level mission.

Shadow Episode - Completed 40 points: Clear unlocked Shadow difficult level mission.

Silver Episode - Completed 40 points: Clear unlocked Silver difficult level mission.

Shadow Episode - Mastered 60 points: Clear all unlocked Shadow ACT Missions with Rank S.

Sonic Episode - Mastered 60 points: Clear all unlocked Sonic ACT Missions with Rank S.

Silver Episode - Mastered 60 points: Clear all unlocked Silver ACT Missions with Rank S.

Nights of Kronos 60 points: Unlock the complete ending to the last hidden story.

Legend of Soleanna 100 points: Overcome all trials and accomplish a great feat.

Silver Medalist 50 points: Collect all the Silver Medals scattered around Soleanna...

Gold Medalist: 50 points: Collect all the Soleanna legendary Gold Medals...

Blue Phantom 20 points: Super Sonic Obtain the all moves.

Ultimate Life Form 20 points: Resurrect the ultimate power from the lost memory.

Psychic Soldier 20 points: Obtain all the power to save the future world.

Soleanna's Hero 40 points: Solve all Soleannans' problems.

Elite Agent 40 points: Complete all the tasks given as agent.

Silver The Liberator 40 points: Solve all the mystery in Soleanna.

Soleanna's blue wind 50 points: Solve all the problems swiftly.

Dark Hero 50 points: Meet all the requests with magnificent skill.

Silver The Savior 50 points: Reveal all the secrets with your ultimate power