Unlike the title says, this thread is not about two kids trying to top each other; it's about who you would like to see in combat against each other and what kind of battle.
Fights can range from two people duking it out with that old boxing game from the eighties, crazy sword fights, sniper duels, mudwrestling, American Gladiator style, or anything you think would be cool. Heck, it could be just two members swinging at each other in the street.
My favorite imagined battle would between Shlup and Raist. They'd both have sledgehammers and be battling on an outdoor basketball court. I imagine there could be a lot of potential in that.