Aero The Acro-Bat, Making of…
Aero the Acro-Bat was a short lived and underrated game from Sunsoft. The original game, released in 1993 on the SNES and Mega Drive, featured a red bat named Aero, who had to rid his circus of an evil clown. This was right down Sonic the Hedgehog territory with 2D platforming action, involving taking out the enemy with a drill attack or a limited amount of shooting stars. Kombo.com recently featured the development process of the game with creator David Siller and some very insightful rough draft concept illustrations.
http://www.kombo.com/features/Taking..._The_Acro-Bat/
http://www.kombo.com/features/Aero_T..._Game_Concept/