AKA The Stranger, AKA Captain Luthor, this multiverse refugee comes from a version of Earth where Kal-El didn't find Lois Lane and his half brother, Tol-Rho convinced him to join Rho's crusade to bring back Kryptonians by infusing their consciousnesses into human hosts turning them into a Kryptonian. John Henry Irons, married to Lois Lane (of his Earth) had a daughter Natalie. After the death of Lois Lane at the hands of Kal-El, "Nat" and Irons worked to build a suit that could stop Kryptonians using stolen Luthor Corp products. This lead to the AI in the suit referring to him as Captain Luthor. It wasn't until Lois Lane and Kal-El of Earth Prime showed Irons that our Earth's Superman is different. It was then that Irons dropped the Captain Luthor moniker and began using his real name again.

Note, the Earth Prime version of Irons was killed years ago in a military operation. He never met Lois Lane of our Earth.