3. Clayface
Clayface is the alias of several Batman villains, all of whom generally have the same power - a bodily composition made up of a mud-like substance that allows them to shapeshift and augment their physical strength accordingly. The original Clayface was an actor - Basil Karlo - who was driven insane when a horror film ('
The Terror') that he had originally starred in was remade without him. This led to him donning the mask of the film's killer - Clayface - and killing the actors in the order that they would die in the film, culminating in him killing the actor playing the Clayface killer. He is stopped by Batman and Robin, however. He then meets another Clayface - Sondra Fuller - and they propose an alliance, along with other Clayfaces (called 'The Mud Pack'), to kill Batman. After having injected himself with samples from the other Clayfaces, Karlo develops their powers but is ultimately defeated by Batman and his allies again. Whether or not a movie version of the Clayface character would be a lone villain or part of the Mud Pack is open to debate, but it would make for an awesome looking CGI character and would pose a genuine physical threat to the caped crusader.