Kit Harington is confirmed to debut as the Black Knight in Marvel's Eternals movie - and he could help set up the X-Men, too. Next year, viewers will be introduced to Dane Whitman, aka the Black Knight. He's heir to a legacy that runs all the way back to the days of King Arthur, when Merlin chose the first Black Knight and granted him an enchanted Ebony Blade that had been forged from a meteorite.

The first Black Knight was Sir Percy of Scandia, who was protected from death so long as he held his sword. He adopted a classic double identity, feigning incompetence in his "civilian" role, while secretly working against Arthur's traitorous nephew, Mordred, as the Black Knight. Unfortunately, Mordred obtained another sample of the meteorite metal, and forged a weapon of his own. That proved able to break the Ebony Blade's enchantment, as Sir Percy learned when he sustained a fatal injury.

Related: MCU Theory: Eternals Explains Why So Many Infinity Stones Were On Earth

The Ebony Blade passed down through Sir Percy's family line, and countless other individuals - some heroes, some villains, some more ambiguous - have claimed the title of the Black Knight. That means Marvel Studios is implicitly absorbing an entire line of mystical characters into the MCU's history, and that raises some intriguing possibilities.

One Black Knight Encountered Early Mutants

Black Knight Exodus

One notable Black Knight was Eobar Garrington, who served in the Crusades in the 11th and 12th century. He participated in the siege of Jerusalem in 1099, and proved to be one of Richard the Lionheart's most dangerous warriors. Influenced by the Ebony Blade's blood curse, he cut a swathe through Richard's enemies. In the aftermath of the siege of Jerusalem, this Black Knight heard rumors of an ancient power hidden in the deserts of a land called Akkaba. King Richard commissioned the Black Knight to lead an expedition to discover this power, and bring it back for England. This path led Garrington to encounter some early mutants.

In the comics, mutants - such as the X-Men - are essentially the next step of human evolution. The mutant gene would only become active on a large scale in the 20th century, but there were certain evolutionary precursors. One of the most famous of these was the powerful, immortal mutant called Apocalypse, who had once ruled in Akkaba. Apocalypse believed in survival of the fittest, and he was interested in the armies who had successfully sacked Jerusalem. As such, he sent his own operatives to seek out the Black Knight and his companions.

Ironically, in the end, Apocalypse didn't find the Black Knight to be of use at all; instead, he focused his attention on one of Garrington's allies, Bennet du Paris. Paris had a latent mutant gene, and Apocalypse triggered it, activating phenomenal telekinetic power. Fortunately, Exodus was imprisoned in suspended animation in a tomb in Akkaba - and only awoke in the present day, taking up the identity of Exodus.

Related: How Marvel's Eternals Are Different To The Inhumans & X-Men

Could There Have Been Mutant Precursors In The MCU?

Oscar Isaac in X-Men Apocalypse

Marvel Studios president Kevin Feige has confirmed that the X-Men are coming into the MCU. "There's no time left to talk about mutants," he told attendees at SDCC 2019, "and how mutants fit into the MCU." That comment suggests Marvel has already worked out how to introduce mutants - but it remains to be seen what approach they'll take. One possible solution, remarkably close to the comics themselves, is that the mutant gene was introduced into the human race by the Celestials millennia ago, at the same time they created the Eternals. It simply needed an infusion of cosmic energy - say, repeated bursts of energy from Infinity Stones - to trigger the mutant gene on a large scale.

Just as in the comics, then, there could have been infrequent evolutionary precursors throughout history, with these early mutants confused with witches, sorcerers, werewolves, vampires, and the like. Presumably their powers were triggered by alien energies, by physical stress and trauma, or just by exposure to natural radiation. Indeed, there's already evidence that Scarlet Witch could be retconned to be a modern example; the Marvel Studios Visual Dictionary suggested that the Mind Stone may have "unlocked something latent inside her," possibly a mutant gene. That would explain why Scarlet Witch and her brother Quicksilver had such different powers, when they were both experimented upon by the same Infinity Stone.

All this means that Marvel could potentially use the line of the Black Knight to introduce Exodus as an evolutionary precursor of the mutant race as well, albeit one several centuries removed. Exodus is a fascinating character, who shares Magneto's isolationist ideology. It's quite possible Marvel will want to avoid using Magneto for a while; the studio don't like reusing characters and concepts who've already been developed on the big screen. If so, then Exodus could serve as a substitute, and the Black Knight could help to write him into the MCU's history.

How Black Knight And Sersi Can Encounter Exodus

Marvel Comics Exodus

This could be done by copying the comics, and using the Black Knight's Eternal lover, Sersi. In the comics, Sersi possesses the power to travel through time, and even jump to different dimensions. The MCU explored themes of time travel in Avengers: Endgame, and it's set to develop them in the Loki TV series, which will reportedly see the Trickster God use the Tesseract to transport himself through time. Given time travel looks to be quite important to the MCU going forward, it wouldn't be a surprise to see the MCU version of Sersi prove able to manipulate time as well.

If that's the case, it's entirely possible Marvel's Eternals movie can explicitly introduce Exodus. In the Black Knight: Exodus one-shot, Sersi's time travel abilities partly failed her, and as a result she was cast back to the Middle Ages. What's more, the spirit of Dane Whitman actually inhabited the body of his 12th-century ancestor, Eobar Garrington; he was party to the encounter with Apocalypse, and he and Sersi played a key role in imprisoning Bennet du Paris in the first place. Such a story would be a smart way of setting up the mutant race, revealing that Exodus points the way to a darker future in which superhuman powers become a lot more commonplace, and meaning viewers would know just how powerful he is when he arrives on the scene to confront the X-Men.

Next: What Are The Eternals? Marvel’s New Cosmic Movie Team Explained

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