Goku is the legendary Super Saiyan to have surpassed Super Saiyan 2! His power is incredible and he can’t be stopped by almost any being in all of media. His power is too great and he crushes his opponents with ease. Master Roshi taught Goku some of what he knows, but the fact is that Goku surpassed Master Roshi long ago. Master Roshi doesn’t have nearly enough power to stop Goku now. Goku wins.
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Master Roshi beats Kid Goku before fighting in his second tournament. After that goku beats him hands down.
Yeah, nowadays beating Roshi would be a cinch 😀