Sadly (and hilariously) Mr. Satan is in fact a representation of everything that is America (or according to them). The fact he's a loud jack ass who thinks he's the strongest in the world, how he always gets credit/glory, the afro hairstyle, the Macho Man Randy wrestling moves, and the fact he's called "Mr. Satan".
It's Japan's way of saying we are the devil, and were big mouthed morons who act like were god. In a way it's the ultimate insult but the character turned out to be so popular and people enjoyed him so much, his part was expanded even longer through out the Majin Buu saga.
If they do make more DBZ movies and eventually get to Mr. Satan's part, seeing him on the big screen would be worth the ticket price alone
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