Dr. Gero

Dr. Gero (ドクター・ゲロ, Dokutā Gero), also known as Android 20 (人造人間20号, Jinzōningen Nijugō), is a supporting antagonist in the Dragon Ball franchise, appearing in the Dragon Ball manga and the animes Dragon Ball Z and Dragon Ball GT. He is a genius scientist who is the mastermind behind the Red Ribbon Androids.

Dragon Ball Z
Android Saga-80,000,000

Dragon Ball GT
Super 17 Saga-80,000,000

Dragon Ball Online
Red Pants Army Saga-80,000,000