" on the Sonic Fanon Wiki . These are by fans—they describe stages, bosses, and missions for a game that does not actually exist in playable form.
There is no official ROM for the Nintendo DS, as the game was originally released for the Xbox 360, PlayStation 3, Wii, and PlayStation 2. However, there are popular fan projects and related ROM hacks that bring this experience to the handheld. Fan-Made DS Projects Sonic Unleashed Ds Rom