2 Games in 1: Sonic Battle & ChuChu Rocket! is a compilation of two games for the Game Boy Advance. It contains the games Sonic Battle and ChuChu Rocket!. There are no extras, just a menu that lets the player select the two games.
The in-cartridge cheats and unlockables for the these games still work; however, the game enhancer codes do not. The respective cheat page for Sonic Battle can be found here: