Sonic The Hedgehog - Completion bonuses

Sonic The Hedgehog
Completion bonuses:
Get a 100 completion for Sonic, Shadow, or Silver's story to unlock the Audio and Theater room under the Extras menu.

Play as Shadow:
Successfully complete Crisis City with Sonic to unlock Shadow's story.

Play as Silver:
Successfully complete the Silver The Hedgehog Boss battle with Sonic to unlock Silver's story