Marvel could bring back Guardians of the Galaxy Vol. 2's villain Ego the Living Planet (Kurt Russell) in Eternals. The upcoming entry in Phase 4 of the Marvel Cinematic Universe will span thousands of years as it introduces the superhuman beings known as EternalsEternals boasts a star-studded cast to play the powerful heroes, with Angelina Jolie, Salma Hayek, Richard Madden, Gemma Chan, Kumail Nanjiani, and more. The movie is exploring over 7,000 years of MCU mythology thanks to their long lifespans.

Part of Eternals' story will involve how the Celestials created the Eternals. The final Eternals trailer featured multiple Celestials, an ancient and powerful race that previously controlled the Infinity Stones. This won't be the first time the MCU uses the massive beings, as they've quietly been set up through the Guardians of the Galaxy franchise. The Collector's base of operation in the first film was inside a severed Celestial head that became known as Knowhere. The same film even showed Eson the Searcher using the Power Stone to destroy civilizations. Guardians of the Galaxy Vol. 2 introduced another Celestial with Ego, although he looked very different from the rest of his kind.

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Ego's MCU story seemed to come to a close in Guardians of the Galaxy Vol. 2 when Groot set off a bomb inside the planet's core, which functioned as his brain. However, the presence of the Celestials and Eternals' multi-millennia spanning story gives Marvel Studios a chance to bring him back. As a member of the Celestials, Ego could be one of the beings who helped create the Eternals or even the Deviants. While the rest of the Celestials are towering figures, Ego has experience in creating matter and human-like beings. He made his own human avatar to explore the cosmos, so he could've helped pioneer the Eternals' creation as well. Ego would still be dead during the main part of Eternals' story, but the movie can use flashbacks to make him part of their origin.

There are other avenues for Ego to return in Eternals too, even if he wasn't involved in the creation of the main characters. The MCU hasn't explored much of Ego's past, but it is known that he visited thousands of planets over an unspecified amount of time and planted his seed as part of the Expansion. There's no guarantee the Eternals have only spent time on Earth, so Ego and the Eternals could've crossed paths at several different points in the past. But, since they have spent 7,000 years on this planet, they're around when Ego finally comes here in the last 1970s. This is when Ego met and fell in love with Meredith Quill - but he also could've met the Eternals during his many trips to Earth around this time.

It is also possible that Eternals could bring Ego back as it explores what actually happened to the Celestials. The powerful beings haven't been seen in thousands of years and were thought to be extinct prior to Ego's emergence. As Eternals explores the history of the Celestials, Eternals, and Deviants, the whereabouts of the Celestials can be revealed. Ego could have played a role in whatever happened to them, as he is one of the galaxy's beings strong enough to kill another Celestial. With so many possibilities for Ego's MCU return, hopefully it does happen in Eternals after all.

MORE: Is Galactus A Celestial? Eternals MCU Link Explained

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