John Achilles was an archaeologist turned criminal who pretended to be the descendant of Achilles. He encased his right foot in a steel box called the “magnetic repeller” to make people believe that he shared the weakness of the mythical Achilles’ heel.
He finally met his end when he was cornered by Superman and tried to leap across a river, but was ironically dragged down and drowned by the steel box that was supposed to protect him.