The Marvel Cinematic Universe is expanding with the introduction of the race of alien immortals in Eternals, and a few of them have been Avengers in the comics, at one point or another. In fact, in Marvel Comics, the Eternals are some of Marvel's most powerful characters.

Confirmed at SDCC 2019 to be the second film on Marvel's Phase 4 slate, Eternals will be released in November 2020. Directed by Chloe Zhao, the upcoming movie will tell the story of the immortal Eternals, who were created by the Celestials and sent to Earth to battle the Deviants. Since the Eternals have lived for thousands of years, the film is expected to explore the ancient history of the MCU. Eternals boasts a star-studded cast with Angelina Jolie as Thena, Salma Hayek as Ajak, Richard Madden as Ikaris, and Kit Harington as Black Knight.

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The Eternals are the creations of legendary comic book writer Jack Kirby, who gave them in their own series in the 1970s. After the series was cancelled, the group returned for a few other, short-lived titles, miniseries and guest appearances in other characters' comics. The Eternals as a team were never featured prominently in Marvel Comics, but individually, some have played important roles in some of Marvel's biggest stories. Three, in fact, have served as members of Earth's Mightiest Heroes.

Starfox

Starfox smiling fwhile fliying in space in Marvel Avengers

Eros, who was later nicknamed "Starfox" by the Wasp, is separate from the main group of Eternals and has limited contacted with his Earth-based cousins. Starfox and his brother Thanos are members of a different branch Eternals who live on Saturn's moon, Titan. Starfox, apart from his many abilities as an Eternal, is distinguished by his "empathic powers", which allows him to mentally influence the pleasure centers of the brain.

In 1984, Starfox became the first Eternal to join the ranks of the Avengers. His love for adventure led him to seek out Earth's Mightiest Heroes, believing that saving the world with them would fill a hole in his life. Though he joined the team simply to entertain himself, it didn't take long for the responsibilities that came with being an Avenger to sink in.

Starfox soon became a valuable member of the group, despite the fact that some of the Avengers felt uncomfortable around him due to the nature of his powers. But over time, Starfox gained the respect of his teammates and developed a close friendship with Monica Rambeau. The amount of time Starfox spent with the Avengers and his contributions to the team make him one of the most important Avengers still missing from the MCU. Starfox is one of the few Eternals in Marvel Comics who hasn't been cast in the MCU movie, but this shouldn't be surprising given that he isn't even part of the group that the movie's story is based on.

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Gilgamesh

Gilgamesh Captain America

Don Lee's character in Eternals, Gilgamesh aka The Forgotten One, is potentially the most tragic characters in Eternals comics. Gilgamesh was disliked by his fellow Eternals for his decision to break their rules and meddle in human affairs. As the strongest of all the Earth-based Eternals, Gilgamesh is strong enough to rival Marvel's most powerful heroes, including Hulk and Thor. In the past, Gilgamesh used his immense strength to perform heroic deeds on the behalf of the humans. His actions angered the Eternals to a point where their leader, Zuras, banished Gilgamesh to a small corner of the Eternal city of Olympus. His punishment is what earned him the title "The Forgotten One". His name was not allowed to be spoken, and to this day his real name has still not been revealed.

Interestingly, the name "Gilgamesh" actually comes from his brief time as an Avenger in 1989. After centuries of living in exile, he returned as "Gilgamesh" and joined a new team of Avengers put together by Steve Rogers, who had recently lost the Captain America mantle to U.S. Agent. Gilgamesh's power easily made him one of the strongest Avengers ever to serve on the team. Unfortunately, his time with the team was cut short when he was mysteriously injured. Apparently, his banishment to such a small sector of Olympus lasted for so many centuries that his essence had become bound to it. For this reason, it was determined that Gilgamesh couldn't go back to Avengers Mansion with his teammates. Thus, Gilgamesh's days as an Avenger lasted less than a year.

Sersi

Sersi is an unusual case when compared to the other Eternals. As a fun-loving party girl, she enjoys living among the humans and even uses her powers in the pursuit of fun and entertainment. Like all Eternals, Sersi is capable of manipulating matter, but the extent at which Sersi can use this ability is off the charts. Using this power, Sersi can effortlessly alter any living organism's atomic structure, which means she can transform any living thing into whatever she wishes.

Sersi's association with the Avengers began in 1990 when she developed an unlikely friendship with Captain America, who often called on her for assistance. After realizing how valuable she could be to the team, Steve offered her membership in the Avengers. Sersi stayed with the team for a few years, using her powers to assist them in their battles with Nebula, Doctor Doom, and more. Her most important arc came in the early 1990s when she became part of a love triangle that involved Black Knight and Crystal. Sometime after falling in love with Black Knight, Sersi was infected with an Eternal disease that apparently caused her to develop aggressive - sometimes even murderous - tendencies. The Eternals believed that if they bonded her psychically with the object of her affections, Black Knight, Sersi's mind could be saved. Black Knight was given no say in the matter. When her condition worsened, the two were forced to leave the Avengers.

In Eternals, Sersi will be portrayed by Gemma Chan, while Kit Harington will play the role of Black Knight, a character whose only comic book connection to the Eternals is his relationship with Sersi. The inclusion of his character in the movie could be an indication that their story will be adapted in Eternals.

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