Sonic X-treme

Sonic X-treme is a cancelled platform video game that was in development between 1994 and 1996, by Sega Technical Institute (STI). Had it been released, X-treme would have been the first fully 3D Sonic the Hedgehog game and the first original Sonic title developed for the Sega Saturn. Concepts for the game looked to build on the success of past Sonic games while introducing new elements to take Sonic into the 3D era of video games.