In April 1990, Sega wanted a character to replace Alex Kidd as the company's mascot. One of the designs was a caricature of Theodore Roosevelt. This became the basis for the design of Dr. Eggman. They wanted a character that was the opposite of Sonic, a character that would represent technology and development. The character was also designed to be easily drawable by children.
Eggman is a distinguished scientist and mechanical genius with an IQ of 300. He is an expert in the field of robotics. Despite all this, Eggman uses intelligence on purposes. He attempts to conquer the world and create his own utopia. Despite many setbacks, he never gives up and he does not care what others think of his actions. He considers anyone who opposes his plans a serious threat. Despite his intellect, Eggman is often very childish. He sometimes behaves like a baby when he is in trouble.