Rhinosaurus is an invention created by Willem Viceroy in McFear Factor that is designed to fart out one's worst fear. When he released it into the school, the robot caused utter chaos amongst the children. When the ninja came to save them, the Rhinosaurus farted out his worst fear and soon after Viceroy and Hannibal McFist kidnapped him in their hover-ship. Unfortunately for them, the Rhinosaurus also farted out their worst fears and their whole plan to destroy the ninja ended up backfiring, resulting in the ninja successfully escaping. When the Rhinosaurus was destroyed after falling a considerable number of feet to the ground, every phobioid disappeared.
- Rhinosaurus, rusted over, makes a minor appearance in the episode "Escape from Scrap City".