Yo~, sorry for not uploading any ideas in a while, I have been busy with my college work and I haven't had any free time in the last month.
Anyway, here is a brand new idea that I haven't seen anyone do before.
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After his betrayal by the hands of Black Zetsu and his talk with Hashirama, Madara passed away.
However... He was given another chance.
When Madara awakened from his slumber, he found himself being a baby, looking at weird creatures of various colours.
Madara Uchiha, has been reborn as a Sayian before it's destruction. (Give him the sharingan too if you'd like.)
He was sent off to a different planet before its destruction however unlike Goku he wasn't sent to earth, he was sent to a planet inhabited by various beasts.
Now with endless potential of a Sayian, how strong will the Ghost of the Uchiha become?
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Idk if you want evil Madara or nice guy Madara but you should have him be OP as shit.
Evil Sayian Madara?
Good Sayian Madara?
Madara would obviously not have any knowledge of the DBZ world so try to make him use common sense to figure out most of the shit thats happening.