5 parts Ongoing Zamasu, a trainee under the Kai of Universe 10 is an upcoming prodigy. Smart, skilled, and revered as top of his generation. He is gratified to soon be joining his divine bothering.
It isn't until the Kais of Universe 7 pay a visit and he learns all about the mortal's escapades into the world of the Gods and how they've defined it. Mortals who have dared challenge and even mock those above them. Something he doesn't believe should be allowed as they are the ones tasked to help the mortals, not the other way around. One name in particular that they bring up every time they visit... Son Goku.
Learning all he can about him, Zamasu realizes that as he is now there is nothing he can do about it. Gathering the Super Dragon Balls and making a wish to switch bodies with Goku something goes wrong. The time ring he wears reacts and instead of switching with present Goku, he is sent back in time. Having swapped places with a younger kid Goku.
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