Anything involving the world and/or worlds of Jim Henson's Muppets. Similar to the Multi-verse of the DC and Marvel brands, only with Muppets instead of superheroes; except, of course, for Super Grover.
The evil twin concept is a littledifferent though. I don't think I've ever seen any before in the Muppetverse.
A religous group in which Kermit the frog is their Lord, and The Cookie Monster is the Lord's son. This group does prayer to an image of Kermit The Frog.
-Excuse me are you intrested in our lord and savior?
-Im sorry Im a Muppeterian, I have allready fully converted.