[Drybones]

There is actually one in Tenchi Muyo. In the manga, specifically Vol. 9 of "The All-New Tenchi Muyo"

In the story, Washu is trying to understand Mihoshi's dumb luck and Mihoshi accidentally damages the machine studying her, and it explodes and some how causes Washu and Mihoshi to fuse into one person who calls herself Miu. She kinda looks like Washu's head on Mihoshi's body with a slightly lighter shade of red for her hair. Because of Washu's smarts she is able to CAUSE dumb luck to happen at will, and using this power she defeats all the other characters in the series.

Then the story kinda ends in a disappointing fashion.