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He is from the South Quadrant of the Northern Galaxy. Caterpy is actually not verystrong and he tries to get Goku to give up by tickling him (to everyone's exasperation, Olibu even remarks "South Quadrant must be a very peaceful place"). After Goku hits him, he further displays his weakness by whining about it. Caterpy then attempts to go into his pupa state. As South Kai tells Goku and the crowd, Caterpy would morph into his ultimate form upon hatching. However, the cocoon would take 1,200 years to hatch, so Grand Kai declares Goku the winner by default.