Yes, I remember the rat Joker from "Double Dare," a season 5 episode. He was one of the villains in a "Dark Bunny" program. I believe they introduced the cat Joker on Bionic Bunny (season 12, "Do You Believe in Magic?") Wasn't the cat Joker also in an episode of "Dark Bunny"? Dark Bunny is supposed to be a spinoff of Bionic Bunny, right? So they can have the same villain on both shows?