Dr. Hebereke

Dr. Herekeis trying to get his hands on Rare Medals which he can use to take over the world and he's the true leader of Roborobo Gang (Rubberobo Gang in the dubbed version). He first appears on a TV screen in the headquarters of the Roborobo Gang. During his first appearances, his face isn't visible but his cat is. Once one of the 4 Rubberobo leaders got his/her hands on a Medal, they summoned Dr. Hereke, who then appears as a spiraling cloud in the sky. (Source: Medarot Wikia)