Super Dragon Ball Heroes

Super Dragon Ball Heroes is a Japanese original net animation and promotional anime series for the card and video games of the same name. The series premiered on July 1, 2018, and was produced by Toei Animation without the involvement of Dragon Ball creator Akira Toriyama.

Following the Tournament of Power, a mysterious figure named Fu, who after kidnapping Future Trunks, lures Goku and Vegeta to the Prison Planet, an experimental area which Fu created and has filled with strong warriors from different planets and eras in order to force them into a game where they must collect the seven Special Dragon Balls if they wish to escape.

The Prison Planet was only the beginning of Fu's experiments... Based on the experimental data collected at the Prison Planet, Fu finally begins his real experiment! What is Fu's real goal, and what is his real power? Goku and companions from "Dark Demon Realm Mission" and "Universe Mission" appear! An experiment involving the whole universe and space-time!

After Fu's defeat, warriors and fighters from all over the space-time gather to participate in the Space-Time Ultra Tournament planned by Aeos, the former Supreme Kai of Time. Goku and his allies will face very
powerful opponents.

Reference: https://en.m.wikipedia.org/wiki/Super_Dragon_Ball_Heroes_(web_series)

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