The Sportsman, aka Martin Mantle, was a poor athlete as a child. His father, some sort of a mad scientist, was hugely disappointed with his son, so he gave him an experimental treatment, injecting him with the RNA of a true athlete. He became a sports star in college but soon discovered that the treatment was killing him. So, equipped with a football helmet with a skull on it, baseball uniform pants, rocket skates, exploding basketballs, poison gas-filled golf balls, buzzsaw tennis rackets, and many terrible sports puns, he set off on a killing spree, taking out the famous athletes that fuel society's obsession with sports.
Pros: Buzzsaw tennis rackets are pretty cool.
Cons: I don't even know where to begin here.
How I'd do it: I guess I'd update "Tom Watson" in the pictured golf joke to "Tiger Woods," for one.
Casting Guesses: Everyone knows TV's Hunter Fred Dryer is the best athlete-turned actor (and the only man in NFL history to record two safetys in a game), but sadly he's past his prime. So I say Vinnie Jones.
After The Scarecrow, Ra's Al Ghul, The Joker, and Two-Face, who should be Batman's next enemy in the Batman Begins/The Dark Knight series? Well, as of now we know that Tom Hardy will play Bane and Anne Hathaway will play Catwoman.
Check out the master list for all the villains covered. I've pretty much run out by now. Obviously, there are more Batman villains, but not any of significance that I know of. As of February 2009, no one is confirmed as a villain. Not the Johnny Depp Riddler, not Phillip Seymour Hoffman Penguin, nobody.