Sonic Saturn

Sonic Saturn was a project that was in development in 1995 and 1996 by Sega Technical Institute (STI) alongside Sonic X-treme, though no code or assets were shared between the two games. This prototype was created by Peter Morawiec, the lead designer of Sonic Spinball and the coder of the Sonic the Hedgehog 2 Special Stages. The game ran on an interesting 3D engine that was more "realistic" than the ones used in Sonic X-treme. It seems that Yuji Naka did not like this prototype, and so the Sonic Saturn engine was never used to develop a full Sonic game. STI tried to use the engine to create some Bonus Stages to add in Sonic X-treme and the Sega Saturn version of Sonic 3D Blast: Sonic Pool. Due to the lack of time, they abandoned them in favor of a 3D version of the Special Stages from Sonic the Hedgehog 2 for Sonic 3D Blast.