Doctor Ivo Robotnik, also known as Doctor Eggman, is the main antagonist in the Sonic the Hedgehog series. He is a brilliant but evil scientist with an IQ of 300, who is obsessed with world domination. Eggman is known for his large stature, distinctive mustache, and round body. He constantly creates robotic armies and elaborate machines in his quest to conquer the world and defeat his arch-nemesis, Sonic. Despite his villainous nature, Eggman is portrayed with a comedic flair, often resulting in his plans being foiled by Sonic and his friends.