Alot of the staff between 06 and Billy Hatcher actually overlap: Game Designer for both 06 and Billy Hatcher: Shun Nakamura (director) Atsushi Kanno Programmer Yoshitaka Kawabata (lead programmer for both) Takuma Komatsu Artists: Yoshinare Amaike Akira Mikame Yuki Takahashi Wataru Watanabe It's the movement of Sonic 06 that is precise and binary and less like the other 3D Sonic games up to that point. It's almost like controlling Billy without an egg. Am I crazy. And the combat too. The more enemies you defeat in an area within a time period you get more points. And it makes sense too, because the rest of the staff that worked on 3D Sonic games was at Sonic Team USA at that point. Shun Nakamura said he suddenly received a call on making a new Sonic in Japan (first time since Adventure), and it looks like he basically scrambled together the Billy Hatcher engine and hastily turned it into a Sonic game on new hardware. We see this happening often don't we? Sonic Rush physics was put into Sonic 4, Sonic Lost World morphed into Sonic Forces and now Frontiers is an amalgamation of Lost World, Forces and the battle portions of the new Sakura Wars game.