I'm afraid that wasn't quite what I was trying to say. I meant a more generalized contest encompassing all video games based on comic book properties, not any character done in the graphical style of the Batman: Arkham trilogy. If you want to do a contest focused on the Arkham games, I don't have a problem with that, I just reasoned that there'd probably be more participants/interest if the concept was expanded to be about comic book video games in the broader sense.
In a similar manner, I'd feel that it would be better to have a general video game RPG contest instead of making one that focused solely on Square-Enix's Final Fantasy franchise, again, purely because that would give participants a lot more subject matter and characters to work with.
And, as HeartBreakKid said, a contest focusing on Batman's Rogues Gallery, irrespective of the media they originated in, would also be cool. I was thinking of doing a contest along the same lines a while ago, except with Spider-man's Deadliest Foes instead. The only problem with that, as far as writing the rules go, is how do you decide on a cut off point for who is, or isn't, one of their foes when they've crossed paths with almost every villain in their respective comic book universes over the years? The rule I was gravitating towards was that the hero would have to have fought the villain on at least three separate occasions, but I'm not sure if even that would be adequate, because that could potentially exclude relatively new or under-used villains who are intended to be exclusive enemies of that particular superhero.