Two Face from Batman would be cool. Get a couple of different coloured suits from a second hand store. sew them together. A shirt, tie, make up. Oh and a largish coin and put a few scratches on the "tails" side. If you can find a two headed coin even better.
I love the makeup for the cracked porcelain doll. It always looks so cool! Zombies are fun, but I think it's a bit overdone. I was going to be the Joker. (He's my favorite character from Batman!) My bf is going to be him, and I'm going to be Harley Quinn. I'm making the costume myself though. I hate how short the costumes are, plus they're overpriced. I think being two faced (non-Batman) is cool. You could do one side of your makeup really pretty, and the other side dead and creepy.