Unlockables

Last Episode
     To  Unlock  the  Last  Episode,  beat  Sonic's  Episode, Silver's
Episode, and Shadow's Episode.

Unlockable 	       How to Unlock
Last Episode 	       Beat Sonic's Episode, Shadow's Episode, 
                       and Silver's Episode

Unlock 'Extras' Menu
     Complete  either  Sonic, Shadow, or Silver's story 100% to unlock
the Extras menu on the main menu.

Unlockable 	        How to Unlock
Audio Room 	        Complete Sonic, Shadow, or Silver's story 100%
Theater Room 	        Complete Sonic, Shadow, or Silver's story 100%

Unlockable Characters
     Meet  certain  requirements in Sonic's story to unlock Shadow and
Silver's stories.

Unlockable 	        How to Unlock
Shadow the Hedgehog 	Complete 'Crisis City' with Sonic
Silver the Hedgehog 	Complete 'Silver the Hedgehog' boss battle with Sonic