'Doctor Ivo Robotnik' (ロボトニックRobotonikku?),[3][4] also known by his alias Doctor Eggman (ドクター・エッグマンDokutā Egguman?),[5] is a fictional video game character and the main antagonist of the Sonic the Hedgehog series created by Sega. Dr. Eggman is a rotund, mad scientist with an IQ of 300 who plans to conquer the world in order to build his Eggman Empire and is the archenemy ofSonic the Hedgehog. His character designer is Naoto Ōshima, and while he has gone through several large appearance changes throughout the series, his design retains several basic characteristics, such as his egg-shaped body and his large mustache. Despite his scientific skilled mind, he is horribly immature and often tends to throw temper tantrums, mostly whenever his plans fail. He has appeared in almost every Sonic the Hedgehog game since his first appearance and has appeared in all other Sonic media, including comics, TV series, and a feature film.

(Credit to Wikipedia)