Dr. Gero

ドクター・ゲロ

Dr. Gero turned himself into a cyborg by implanting his brain into a robotic body. He first appeared alongside Android #19 with the goal of killing Goku. After Vegeta destroyed #19, Gero fled out of fear, intending to activate Androids #17 and #18. Once he activated them, they quickly rebelled against their creator. #17 kicked his head off and crushed it.
After Goku defeated the Red Ribbon Army, Dr. Gero went into hiding in his laboratory, located in a mountain area north of North City. In this lab, he strove to create the ultimate fighting machine. Using an extremely intelligent tracking device disguised as a ladybug, he studied Goku and the Z Fighters for years, observing Goku's fights with Tien Shinhan, King Piccolo, Piccolo, and the Saiyans Raditz, Nappa, and Vegeta.
Dr. Gero ceased studying Goku's power when the Saiyan left for Namek, believing he had already compiled enough information; so he simply adjusted the androids' power levels to accommodate for Goku's expected power increase, not accounting for the power level of Goku's Super Saiyan form. Believing he had created the ultimate fighting machines, he finalized his plans and constructed a series of Androids. Android 16 was modeled on Gero's dead son, a high-ranking Red Ribbon soldier long ago felled by an enemy bullet. Out of affection, Gero made him powerful, but did not want him to be destroyed in battle, so he made him gentle. While looking for fresh material for his experiments, Dr. Gero met two notorious delinquents by chance, two siblings, a boy and a girl. He then kidnapped them and restructured them into Android 17 and Android 18. However, the two became rebellious as they retained their human free will, so he deactivated them.

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