Metallo Mask and Chest Armor

"Oh, yes. I know who you are. Lois Lane and Clark Kent. Crusading writers for the Daily Planet. Well, you've both lucked into the ultimate story, this time. The story of Metallo! The man who's gonna kill Superman!!"

John Corben is the Kryptonite-powered cyborg Metallo, one of the oldest and most dangerous enemies of Superman.