Sonic Xtreme, the 3-D Sonic game that originated on the Nights engine, then got scraped because Sega Jap is gay, after getting scraped a 2nd attempt with a new engine was made, the engine sucked too much so they couldn't finish it, Sega Saturn and 32X went to craps so sega said fuk a new sonic game, and in the end, released the horrible engine's game titled as "Sonic 3-D Blast". It has a lot of history, GOOGLE!