Filming is still underway on Marvel's Avengers: Infinity War, so much what is known about the plot right now is speculative. But, like any superhero film, what fans are most clamoring to learn is who the heroes will be squaring off against. Marvel has long been building toward a showdown between the Avengers (and friends) and Thanos, the Infinity Gauntlet-wielding Mad Titan. Now we may have reason to believe Thanos will be joined by -- dun, dun, dun -- his own children.

After leaked photos from the Infinity War set sparked rumors that Thanos would be calling on the Black Order, a group of lethal aliens, to do his evil bidding, MCUExchange proffers that the Black Order will actually be the children of Thanos and may not even be called the Black Order, as they are known in the comics. These offspring have already been mentioned in the recent Guardians of the Galaxy Vol. 2 by Nebula, who tells Gamora that "out of all our siblings, I hated you least." Nebula and Gamora are both the adopted children of Thanos. So, while comic readers will know Thanos' evil-doers as the Black Order, Infinity War may just refer to them as Thanos's evil kids.

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So who are these evil, potential offspring of Thanos?

It's now common knowledge that motion-capture performer Terry Notary is playing Thanos "right-hand bad guy" alongside three other actors, and in the comics that character is Corvus Glaive. Corvus, who looks a bit like the grim reaper, is a self-proclaimed destroyer of worlds, with superhuman strength and speed -- not to mention immortality as long as his weapon, a glaive, stays intact.

Other pictures hint at the inclusion of Proxima Midnight, as well. She is the wife of Corvus Glaive in the comics, though that might be changed to sister if the rumors pan out. Proxima is similarly strong, fast, relatively invulnerable and known for her combat skills. She fights with a spear made by Thanos that holds the mass of a star in it, basically immobilizing any target with a huge amount of energy.

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There is also speculation that Wakanda, the setting for February's Black Panther, is a premier location in Infinity War, and thus Black Order member Black Dwarf is also a likely member of the Thanos team, as he invades Wakanda in the comics. Black Dwarf is Thanos power-hitter with his super-strength and impenetrable skin.

No sign yet of the Black Order's other members: Ebony Maw, a devious super genius, and Supergiant, an unhinged telepathic mental parasite who can control her victims.

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Karen Gillan's Nebula (from the Guardians of the Galaxy films) has already been confirmed to appear in the film, and her strained-at-best relationship with her father could lead her to either oppose or join him.

Avengers: Infinity War is directed by Anthony and Joe Russo and premieres May 4, 2018. The cast includes Robert Downey Jr., Josh Brolin, Mark Ruffalo, Tom Hiddleston, Chris Evans, Chris Hemsworth, Jeremy Renner, Chris Pratt, Elizabeth Olsen, Sebastian Stan, Benedict Cumberbatch, Paul Bettany, Samuel L. Jackson, Cobie Smulders, Benedict Wong, Zoe Saldana, Karen Gillan, Vin Diesel, Dave Bautista, Pom Klementieff, Scarlett Johansson, Tom Holland and Anthony Mackie.