In one of of the many Kamen Rider worlds, Y/n, is a normal young man, until his homeworld was destroyed. But just when he was about to die, he was saved by a cloaked man in a time mazine. The man told Y/n that there's a way to save his world from being destroyed. He must travel through his timeline and other worlds to collect the ridewatches and become Kamen Rider Zi-O. However, unlike the original Zi-O, this story may find Y/n a little bit of an anti-hero, as his quest is to not collect the original ridewatches, but the ridewatches from all 19 dark riders.

(Y/N): "Henshin!!!!!!" (Y/N) (L/N) Nguyen was the chosen one for Kuuga ...after the second of legend Kuuga who sacrificed for himself to the sake of humanity and he was died battle with Daguva the strongest leader of Tribe Grongi and no matter how that he is...he will died. The two legends die and they both went to hell or heaven...then Yuusuke Godai is gone forever and the Arcle belt was gift to young man (Y/N)...the third Kuuga and he will be the protector for the mankind of this world. No matter how (Y/N) must do and he must promise to himself that he must fight for love and smiles of everyone that he care. Will he be able to defeat the Grongis by himself? Or does he need to be fight for the humanity's sake?