Steel is a superhero appearing in comic books published by DC Comics. He is a genius engineer who built a mechanized suit of armor that mirrors Superman's powers, and initially sought to replace him after he was killed by Doomsday. After Superman was resurrected, he accepted Steel as an ally. His real name is John Henry Irons and he wields a sledgehammer—this is a reference to the mythical railroad worker John Henry. He has a niece named Natasha Irons who is also a superhero in a similar mechanized suit of armour.

Doomsday is a supervillain appearing in American comic books published by DC Comics, commonly as one of Superman's deadliest foes. Created by writer-artist Dan Jurgens, the character had a cameo appearance in Superman: The Man of Steel #17 and made his first full appearance in Superman: The Man of Steel #18.