On tonight's episode of Superman & Lois, titled "O Mother, Where Art Thou?," fans learned Morgan Edge's master plan for Smallville, as well as exactly what his relationship is to Superman himself (hint: he's not a twin, as we previously assumed, but still a biological relative). More important to comic book fans, audiences learned how Edge was managing to vacate human consciousnesses from their bodies and replace them with Kryptonians: a device, invented by Superman and Edge's mother, named The Eradicator. This marks the first live-action appearance of the Kryptonian artifact, which was created by Roger Stern and George Perez in the comics.
In the TV series, The Eradicator is a device invented by Superman's mother, intended to save the minds and souls of Kryptonians after the destruction of the planet. A similar process was used, Jor-El explains, to put his consciousness into the Fortress computer.
In the comics, The Eradicator is a Kryptonian AI, invented by a distant relative of Superman's, which was responsible for the deaths of billions when Krypton was destroyed, because it had created a genetic link between Kryptonians and their planet, preventing them from leaving the world. It was a biological weapon meant to be wielded as part of a clone war on Krypton, but it backfired when the planet itself became unstable.
When The Eradicator was blown away from the wreckage of Krypton, it ended up in the hands of a cleric in space (this character was once referenced in an episode of Supergirl, but never seen), who eventually gave it to Superman when they encountered one another.
After bringing it home to his apartment, The Eradicator briefly took control fo Superman, turning him into The Krypton Man -- a character who wanted to wipe out Earth and terraform it to suit Kryptonian biology (this is the same plot from the movie Man of Steel, but with Superman replaced with Zod and no Eradicator influence). Superman was slapped out of it by Lois and his parents, who reminded him of who he is and prevented any bloodshed. He threw The Eradicator into the sun, where it would melt...but its AI would fashion itself an energy-based body, and it became a living, talking villain for a time.
It seems likely that the "Krypton Man" persona is what we are seeing when Superman wears black and attacks humanity on John Henry Irons's Earth.0comments
After Superman died, there were four "Supermen" who appeared to replace him: a teenage clone (currently appearing on HBO Max's Titans), Hank Henshaw (Supergirl), John Henry Irons, and The Eradicator. Realizing that there is no preservation of Krypton without preserving its last son, The Eradicator was responsible for the super-science that brought Clark back from the dead, and then he became a supporting character and antihero in the comics for years, only recently returning to being a straightforward villain.
Superman & Lois airs at 9 p.m. ET/PT on The CW, following episodes of The Flash.