Rave Master - Special Attack Force for the Game Boy Advance, specifically the '(U)(Floppy)' release, is likely a ROM hack, a fan-made game based on the Rave Master anime/manga. There's no official Rave Master game on the GBA, hence the unofficial status of this version. Details on the specific gameplay and features will vary greatly from any other version.  The label '(Floppy)' identifies the creator or group behind this particular version.  This game showcases the creative efforts of the GBA homebrew community.

Rave Master - Special Attack Force (U)(Floppy)

Ratatouille (E)(Puppa)