A total conversion mod for Sonic Generations on PC. This mod requires the base game installed from Steam. This unofficial project ports most of Sonic Unleashed's daytime levels from the Xbox 360 version into Sonic Generations on PC.
If you need help figuring out how to use SonicGMI, the ModDB page for the Sonic Generations Unleashed Project features instructions for SonicGMI. Q: Can this mod be used on the PlayStation 3 and Xbox 360 versions of Sonic Generations?