Marvel's Agents of S.H.I.E.L.D. season 6 has introduced a deadly new threat to Earth, the Shrike, but the new alien menace bears a curious resemblance to Superman's Kryptonian crystals. The Shrike infects host bodies with a bat-like creature and transforms them into ever-expanding shards of crystals - and this looks just like how the crystals that formed the Fortress of Solitude in the Superman movies work. Could Marvel be poking fun at the core mythology of one of their rival DC Comics' flagship superheroes?

Stopping the Shrike is the reason why Sarge, the dangerous doppelganger of Phil Coulson, has come to Earth. In this week's episode of Agents of S.H.I.E.L.D., "Toldja", Sarge and his team were taken prisoner by the spy agency and yet, because he was withholding crucial knowledge about the Shrike, the Fake Coulson had the upper hand all along. We now know that the Shrike is an extraterrestrial entity that infects and destroys whole planets; its last conquest was Chronyca-2, the home planet of the Chronicoms. Earth is next on the list and it seems the Shrike are also awaiting the arrival of their mysterious creator. But, just as Sarge looks identical to Phil Coulson, the transformation into crystalline entities the Shrike causes bear more than a passing likeness to Superman's home planet of Krypton. Indeed, the Shrike seems to alter whole planets until they resemble Krypton!

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1978's Superman: The Movie introduced the crystal design of Superman's birth world and his Fortress of Solitude. It was created by production and art designer John Barry, who previously was George Lucas' production designer on Star Wars. Barry's crystal vision of Krypton was a huge departure from the pulpy, sci-fi look of Superman's birth planet seen in DC Comics' Silver Age comics and it has proven to be both revolutionary and influential. Beyond the four Superman movies of the 1970s-1980s, the popular crystal design of Krypton eventually joined the canon of the Superman comics. On television, the crystal Fortress was adopted by SmallvilleThe CW's Supergirl has also maintained Krypton and the Fortress of Solitude's crystalline design, and so has Syfy's prequel series Krypton.

Superman Returns made the Kryptonian crystals the key to Lex Luthor's master plan. Bryan Singer's film was a sequel to Richard Donner's first two Superman movies, and both the Gene Hackman and Kevin Spacey versions of Luthor were ingenious master criminals obsessed with controlling real estate. In Superman Returns, Lex stole crystals from the Man of Steel's Fortress of Solitude and dropped them in the Atlantic Ocean. His absurd goal was for the crystals to create a new Kryptonian continent that would swallow up much of North and Central America, killing millions. As the 'owner' of the new continent, Lex planned to strike it rich by selling that real estate to desperate survivors who need somewhere to live.

In Agents of S.H.I.E.L.D. season 6, the Shrike's plan is a lot more straightforward: the people of Earth will become infected and transform into crystalline entities, wiping out all life on the planet. What the Shrike's mysterious creator gets out of this isn't known yet, but whatever the end goal of planetary destruction may be, it likely wouldn't be as logistically problematic as Lex Luthor thinking he can simply own and charge rent on a new alien continent without any sort of retaliation or retribution from the world's governments or Superman.

Moreso, Sarge revealed that extreme cold is the weakness of the Shrike; in "Toldja", the Agents were able to save the Zephyr from being destroyed by a crystal outbreak thanks to flying their ship into near orbit and ejecting the Shrike-infected. This solution isn't far off from how Superman foiled Luthor in Superman Returns, when the Man of Steel simply lifted Lex's Krypton continent, flew it out of the Earth, and hurled the entire mass into deep space.

All of these similarities could merely be a coincidence, but then again, Marvel may just be winking at DC's Superman crystal obsession since the Shrike apparently transform planets until they resemble Krypton. And, considering S.H.I.E.L.D.'s Daisy Johnson possesses the Inhuman power to manipulate gravity, perhaps fans shouldn't be too surprised if Agents of S.H.I.E.L.D. has Quake defeat the deadly crystal threat of the Shrike in a manner similar to how Superman handled Lex Luthor's crystal continent.

Next: Agents of SHIELD: Fitz's Rescue Could Lead To Ghost Rider's Return

Marvel's Agents of S.H.I.E.L.D. Season 6 airs Fridays @ 8pm on ABC.