WARNING: The following contains spoilers for "Sons of Deviant World," a story in Marvel #4, by Daniel Acuna and VC's Ariana Maher, on sale now.

Marvel has already had a strong presence of genetically modified humans, mutants and otherworldly beings in the MCU, but it's getting ready to tackle a new type of hero in the upcoming movie Eternals. The Eternals and the Deviants have been duking it out since both of these teams first appeared in The Eternals #1 by Jack Kirby, John Verpoorten and Glynis Wein back in 1976.

These adversaries are preparing to battle it out in the MCU, but they have a deep history with each other that shows just how dangerous the Deviants can be. This history spans back millions of years to the beginning of humanity itself when the Celestials visited Earth in an event known as The First Host.

While much of that history has played out in the background of the Marvel Universe, a short story in Marvel #4 just showed how dangerous the Deviants could really be.

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Deviants Alternate Reality 1

Originally. The Deviants were one of three new species that were created when the Celestials geneticist Ziran the Tester experimented on a group of primates. The other two species evolved to become the Eternals and the humans. For tens of thousands of years, the Deviants were the frontrunners, becoming the dominant species in an unevolved Earth. They used this dominion to hold the humans as slaves and build an empire. When the Celestials returned for a second time, the Deviants fought back against their creators and attacked their ship -- but to no avail. The Celestials began slaughtering them which in turn helped the Eternals evolve into the strongest species. The Deviants were then forced to retreat underground.

While the Eternals were born with superpowers, immortality and good-looks, the Deviants were not so lucky. Deviants are often born with discolored skin that appears green or purple. No two Deviants look the same, yet they all appear monstrous when compared to humans or Eternals. Not everything in the Deviants' genes is bad though. They have a supreme intellect and a faster evolution speed which allows them to adapt at a much higher rate than humans.

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In Marvel #4, the Deviants took over the world and became the dominant race on this version of Earth. After the Deviants were forced underground, they used their supreme intellect to develop technology that far outpaced what humanity could produce at the time. The Deviants took this opportunity to return to the surface and declare war on the humans. Every city on every continent fell to the hands of the Deviants. They began implementing mind-control devices into humans that would help educate and program the humans into soldiers and slaves. Some lucky humans were genetically modified into gladiators that fought in front of large deviant audiences.

The Deviants Discuss Humanity

Three of the most formidable and recurring Deviants -- Lord of War Kro, Monarch Tode, and Queen Vera -- can be seen overlooking a gladiator battle with dystopian versions of some famous heroes. The leaders of the Deviants are seen discussing plans to keep themselves atop the food chain and send a genetically modified human to assassinate a religious leader.

The Deviants have no regard for human life and will go as far as enslaving humans to maintain their power. There is no doubt that these villains can rival Thanos in terms of their tyrannical appetites, and this grim alternate world highlights just how much could be at stake when the Deviants crash into the MCU.

Keep Reading: Eternals: The MCU's Most Adorable New God Is Secretly Sinister

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