Sonic Rush

Sonic Rush is Sonic's DS debut, which also introduced Blaze the Cat.

E3 Leftovers
Found with the other graphics, and helpfully prefixed with "e3" are these images. They can be seen in the E3 demo. e3_comsoon_jpn.bbg is a bit more descriptive that the _eng version, and says "Thank you for playing. Play the retail version to see what comes next!".

Test Level
The map z13 is an obvious test map, and even has some unused tiles. The name indicates that it should be Zone 1 Act 3.

Unused Music Portions
After the Fight

Kick the Eggman

The two Boss Defeated themes normally cut off after around 7 to 12 seconds, but are actually about a minute and 30 seconds each. They can be played at full length in the Sound Test, known as "AFTER THE FIGHT" and "KICK THE EGGMAN" when the game is in English, but they do not feature in the official soundtrack.