SPOILER WARNING: This post contains spoilers for Supergirl’s Season 2 finale.

It was déja vu all over again during the final moments of Supergirl Season 2. As the Girl of Steel rocketed skyward into a summer of adventure, the episode flashed back 35 years to the death of Krypton. However, in addition to the familiar, episode-opening shots of baby Kal and tween Kara, the flashback revealed a third Kryptonian pod. Its unseen (but infant-sized) passenger had a literal taste for blood and was cared for by a group of "Dark Kryptonians" (so named in the end credits). As the little ship streaked away, they predicted that "it" would "grow strong" and eventually "reign."

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Obviously this mirrored the end of Season 1, where Supergirl and J'Onn discovered a Kryptonian ship and viewers had to wait all summer to learn it was Mon-El. (At the risk of being immodest, we kind of knew it all along.) Who, then, will viewers meet – and possibly come to fear – starting next season? Here are a few possibilities.

Deja Vu, Indeed

Doomsday
Doomsday in prisoner suit

From our perspective the most obvious is Doomsday. His creation is credited to Dan Jurgens, although he appeared first in November 1992's Superman: The Man Of Steel #17, which was written by Louise Simonson and pencilled by Jon Bogdanove. (His first full appearance was in December 1992's S:MOS #18, by the same creative team.) In any event, Jurgens wrote and pencilled the landmark Superman vol. 2 #75 (January 1993), in which the monster and the Metropolis Marvel exchanged their final, senses-shattering punches.

Of course, both got better; and Jurgens went on to reveal Doomsday’s origin in 1994's Superman/Doomsday: Hunter/Prey miniseries. The creature was the product of brutal Kryptonian experiments in accelerated evolution. The scientists in charge started by placing a baby in a hostile environment, waiting for it to die, and then growing a clone rapidly from the remains. Over time the series of clones grew stronger and stronger, until the final product was a barely-verbal killing machine. Now called the Ultimate, it escaped Krypton and wreaked havoc across the galaxy, from Apokolips to Oa and finally to the planet Calaton, where it was stopped by an energy-being called the Radiant. The Calatonians chained the catatonic Ultimate and shot it into space – as you do – but naturally its capsule crashed on Earth and buried itself deep underground. When the Ultimate/Doomsday freed itself, it rampaged across the United States until it reached Metropolis; and you can guess the rest.

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We like Doomsday for the “bloodthirsty baby” because of its torch-lit, hooded-robe-required surroundings. That’s just the kind of environment we’d expect from a group of sinister Kryptonian science-mages looking to revive forbidden inquiries which were long thought forgotten. Feeding on blood and the potential of “reign” are just the icing on the creepy cake.

Nevertheless, timing is arguably against Doomsday. When Supergirl Season 3 premieres in September, it’ll go up against the final marketing push for November’s Justice League movie. That film will feature the aftermath of Henry Cavill’s Superman giving his life to save the world from Batman v Superman’s Doomsday, so The CW might not want to dip too deeply into the Death of Superman well.

A Different Kind of Eradicator

eradicator-last-son-of-krypton-superman

We’re a little fixated on that word “reign,” but only because it reminds us of Reign of the Supermen!, the 1993 storyline which revived the Man of Steel after his Doomsday-inflicted injuries. ROTS! famously gave the world four “replacement” Supermen, including the Cyborg Superman Hank Henshaw. While Supergirl has already adapted the Cyborg Supes, in the form of David Harewood and an electronic faceplate, it has yet to tackle Steel (John Henry Irons), Superboy (Kon-El) or the Eradicator.

Seen first in 1989's Action Comics Annual #2, the Eradicator was an ancient Kryptonian artificial intelligence which Superman picked up on Warworld. After the Eradicator restored Supes’ powers and costume, he took it back to Earth, where it became an all-purpose plot-generating gizmo. In Adventures of Superman #458 (September 1989) it turned Jimmy Olsen elastic; the next month it created a Fortress of Solitude in the Antarctic; and eventually it mind-controlled Superman into thinking he needed to take over the Earth in the name of Krypton.

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When Reign started, the Eradicator had turned itself into a nearly-exact Superman duplicate, albeit one who wore yellow goggles because it was sensitive to light. As the so-called “Last Son of Krypton,” the Eradicator took a harsher approach to crimefighting, earning the respect of heroes like Guy Gardner but alienating (no pun intended) Superman’s other friends and allies. After being taken out temporarily by the Cyborg Superman, the Eradicator apparently gave its existence to (once again) restore the revived Superman to full health. The character was brought back a few times since then, most recently in an early Rebirth storyline.

We think the Eradicator is a viable alternative to Doomsday because it could also fit into the “secrets Kryptonians were not meant to know” atmosphere glimpsed at the end of Supergirl Season 2. Moreover, it would be better-suited to imposing a new Kryptonian order on Earth than the mindless rampager Doomsday. In the comics, the Eradicator was basically a self-contained terraformer, and in the context of Supergirl would be able to “recruit” both our heroine and her cousin. (Remember, in the late ‘80s and early ‘90s, the only Supergirl was the non-Kryptonian “Matrix.”) Granted, it would be the third season in a row that a Kryptonian (or Kryptonian-adjacent) villain tried to impose a Kryptonian-style system on Earth, but the CW’s super-shows do tend to repeat themselves.

Werewolf of Krypton

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Supergirl vs. Lar-On, from "Supergirl" (2016) #7

A longshot possibility is Lar-On, a Kryptonian werewolf who was created by Denny O’Neil and Murphy Anderson and first appeared in World’s Finest Comics #256 (April-May 1979). Not surprisingly, Lar-On was a Kryptonian scientist who ended up experimenting on himself – as you do – and turned into a were-creature. In that state he killed his wife, and was banished to the Phantom Zone as a result. He was freed from the Phantom Zone by an Earth scientist’s interdimensional experiments, but Superman and Batman stopped him and returned him to the Zone.

Admittedly, “Kryptonian werewolf” does seem to fit best with the spooky vibe we get from the flashback. Lar-On has also reappeared in a Rebirth arc in, yes, Supergirl. However, we’re not sure that justifies all the buildup – even if he did turn Batman into a were-creature 38 years ago in World’s Finest #258.

Not the Biggest Threat?

Wherever the Supergirl producers decide to go, we suspect this latest pod person isn’t Season 3 ultimate enemy. Recent seasons of Arrow and Flash have started smaller, with Tobias Church giving way to Prometheus, and Doctor Alchemy being eclipsed by Savitar. Season 2 of Supergirl followed suit, as Lillian Luthor was defeated and jailed just in time for the Daxamites to show up.

Therefore, we think Doomsday, the Eradicator and/or Lar-On are just the villainous appetizer before Supergirl Season 3 serves up the main course. For next season’s villain our money’s on either General Zod or the intergalactic tyrant Mongul. Both have pluses and minuses. Zod’s advantage is that he’s already been seen, courtesy of Superman’s Silver Kryptonite delusion. However, he’ll have to go a long way to make us forget Terence Stamp’s Zod (from the first two Christopher Reeve movies) and Michael Shannon’s performance in Man of Steel. Zod’s arc would also need to distinguish itself from Astra’s in Season 1. His use of the Eradicator might especially remind viewers of Astra and Myriad.

Although Mongul is basically another intergalactic conqueror, along the lines of the Daxamites or even the Dominators, his big hook is the giant spherical starship Warworld. Its timing might also be unfortunate, since Warworld – introduced by Mongul’s creators Len Wein and Jim Starlin in December 1980's DC Comics Presents #28 – looks an awful lot like another technological terror with enough firepower to destroy an entire planet. Yes, it’s got gladiator pits, but some viewers might not see too far past the whole “that’s no moon” thing.

Still, Mongul would be in a good position to scoop up the bloodthirsty baby’s pod (whatever it contains) and use it against Superman’s homeworld. Since Superman mentioned Warworld in Season 2 finale, we’re pretty sure he’s squared off against Mongul already. The extraterrestrial tyrant could send Doomsday to Earth to kill Superman early in Season 3, leaving Supergirl to split her time between National City and Metropolis for a few months. (She could even bring in Earth-1 help like the Flash and Firestorm.) The back half of the season might find her trying to revive Superman as Warworld approaches Earth, setting the stage for another carnage-filled season-ending two-parter.

Finally, Mongul might offer Supergirl a villain who’s not necessarily a dark reflection of the show’s main character. Merlyn, Deathstroke and Prometheus served that function on Arrow, while Reverse-Flash, Zoom and Savitar did the same on Flash. On Supergirl, Astra and Rhea were “dark mothers” (for lack of a better term) who wanted to protect their heritage and/or enforce their skewed moral codes. While that’s not quite what the earlier series did, it does seem like Supergirl may want to switch things up a little. As a blunt, brutal dictator, Mongul risks being a one-dimensional chauvinist; but he also allows Supergirl more opportunity to, shall we say, comment on current events.

Regardless of what’s in store for Season 3, we’re confident that the Supergirl crew can make it entertaining. Besides, we’ve got all summer to speculate.

Got a guess about who’s in the most recent mystery pod? Let us know in the comments!