We've known for a while the Worldkillers are coming to Supergirl. Season 3 has promised to depict the gradual evolution of the season's main villain, Samantha Arias (Odette Annable), into the Big Bad known as Reign. A single mom living in National City who now works for Lena Luthor's (Katie McGrath) L-Corp as its new CFO, Sam is thus far unaware of her true Kryptonian origins. However, she's getting more and more clued in and terrified that there's more to her than she realizes. She has been receiving strange visions and horrific flashes of what are likely repressed memories. In this week's episode 'The Faithful', Sam came face to face, not just with her own visage covered in tattoos of Kryptonian symbols, but with a hooded apparition who promises that "soon you will reign."
Is this apparition another Worldkiller? One thing is for sure: there are more Worldkillers than just Reign and they are definitely on Earth. The season 3 premiere of Supergirl revealed that a Kryptonian ship rests beneath National City. It was unearthed by a missile explosion from a nuclear submarine that Supergirl (Melissa Benoist) foiled, though the presence of the ship remains unknown to anyone in the city. This week, when Supergirl used her heat vision to blaze a hole deep into the Earth so that Alex Danvers (Chyler Leigh) could drop a Betahedron - a Kryptonian device containing the historical and biological lore of Krypton - into the hole before its explosion destroyed National City Stadium, the detonation awakened the systems of the dormant ship. We also saw five stasis tubes in the ship, which is now online.
In DC Comics, the Worldkillers are genetically engineered aliens created by Kryptonian scientists to become like the Worldkillers of Kryptonian myth, each with the power to destroy entire planets. Most of their origins are shrouded in mystery, such as why this project was undertaken to begin with, but the Kryptonian Council outlawed the Worldkillers out of fear of weapons of such power.
Supergirl battled four Worldkillers, led by Reign, for the fate of Earth after rejecting Reign's offer to join them. The other Worldkillers are called Perrilus, Deimax, and Flower of Heaven. Initially overpowered by the 4 on 1 disadvantage she faced, Supergirl won the battle when she realized that only a Worldkiller can kill another Worldkiller. Supergirl used the Worldkillers' powers against each other, until Reign stopped the fight and fled the Earth rather than risk the deaths of her fellow Worldkillers. Upon departing, Reign cryptically told Kara of a fifth Worldkiller; some fans speculate this mystery Worldkiller to be Doomsday, the living engine of destruction who once killed Superman.
Supergirl is clearly taking the basic idea of the Worldkillers and doing an entirely new spin on it, starting with Reign herself. Samantha Arias is a complete reboot of the more monstrous comic book Reign, as is the concept of her living on Earth thinking she is human. Ironically, season 8 of Smallville did a similar type of story with its version of Doomsday: a paramedic named Davis Bloom (Sam Witwer) dreamed of committing horrific mass murders before realizing he was actually transforming into the Kryptonian monster Doomsday. Supergirl's Samantha seems to be headed down a similar path of slowly uncovering the truth about herself.
The apparition Samantha sees in her bathroom could be one of the Kryptonian scientists who created her, though the hooded demonic-faced woman could also be tied to a fanatical religious sect of Rao worshippers on Krypton. Supergirl seems poised to answer the question the comics have not: why were the Worldkillers created? Introducing human followers of Rao who worship Supergirl in "The Faithful" may be planting the seeds for juxtaposing how worshipping Rao on Krypton led to the creation of the Worldkillers, who were also sent to Earth when Krypton died. Since the final shot of 'The Faithful' showed five stasis tubes, we can infer there are four more Worldkillers in National City, not counting Reign herself. Though Supergirl is also heading towards this year's Crisis on Earth-X Arrowverse crossover as well as finally revealing the fate of Mon-El (Chris Wood), it won't be too long before the series releases the Worldkillers.
Supergirl airs Mondays @ 8pm ET on The CW.