I had an idea of doing a Team Magma/Aqua challenge. You would choose a team and your pokemon would have to correspond. Magma would get Fire and Ground. Aqua would get Water and Dark. They cannot intertwine though; for example, Swampert, Quagsire, etc. would be banned because they are both Water and Ground. There would be exceptions, though, Magma can use Mightyena and Absol, and a few other dark types. They would both be able to use the Crobat line, the Weezing line, Raticate line, Linoone line, Watchog line, etc. The only problem I think is that I feel like it's kind of just another "here's the criteria, so pick a pokemon" game, but it's new!
Also, has anyone thought about the alphabet challenge before? I though I saw it here but I don't see it..