Doomsday

Doomsday is an early descendant from the planet Krypton, as he was created to be the perfecf killing machine, as he's able to regenerate each time after death becoming immune to whatever killed him before. Problem? He sees anything that's alive as an enemy, so he'll try to destroy anything and anyone that lives. You can be Superman, Supergirl, or anyone from the DC universe you want. Or, you can use an OC. Have fun.