Very early in development, Tails was intended to be trapped inside the robot, but this was too difficult to work into the story so it was scrapped. These included a long laser shot from the eye, homing missiles from all ten fingers, and 'Super Gravity Smash', a move where its chest armor would open and fire a gravity bullet that would eventually disappear but would draw in Rings if the player was too close to it. The robot was intended to have many attacks during development, but time constraints resulted in several of its abilities going unimplemented. The robot used imagery from Mechagodzilla and Gigan for its design, making it appear strong and painful.
Eggman's first combat unit to counter only Sonic, unlike other Badniks which were created out of ambition. Mecha Sonic's creator, Yasushi Yamaguchi, has stated that Mecha Sonic was written as Dr. Mecha Sonic's design based on its sprites (top), and early sketches (below).