Sonic Rush Adventure Cheats

Collect all sol and chaos emaralds and it unlocks the deep core stage where you get to play as super sonic or super blaze

-Muzy (Sound Test)
After defeating the Titan boss in Big Swell, go to Seagull Beach on Windmill Island and talk to the koala with the guitar. You will now be able to listen to music, sound effects and dialogue from the game, and can receive missions which unlock extra sounds once completed.

-Blaze the Cat
Defeat the Kraken boss in Coral Cave (World 3) to unlock Blaze as a playable character.

-Extra Ending

To get blaze (the cat) just beat tha boss of zone 3 (coral cave) and you will see a cut scene of blaze attacking captin whiskers and blaze surprized about seeing sonic after getting back to her own world in sonic rush.