Eternals’ Post-Credits Cameo Retcons Thanos’ Past

WARNING: This article contains spoilers for Eternals.

The post-credits scene in Eternals retcons what was previously known about Thanos’ past in the MCU. One of the movie’s most surprising moments occurred after the credits when two Marvel Comics characters – Starfox and Pip the Troll – came aboard the Domo and confirmed that the former has an important link to Thanos. Apparently, Starfox is Thanos’ brother.

Played by Harry Styles and dressed in a comic accurate red-and-white costume, Starfox has served as a shocking and sudden addition to the MCU’s growing library of characters. Given that Starfox aka Eros was a major member of the Avengers during the mid-1980s and a superhero with an important role in a number of cosmic storylines, there’s a good chance that Starfox’s appearance in Eternals will amount to much more than just a one-and-done cameo. The impression left by his introduction is that the Titanian superhero will play a role in the rescue of Phastos (Brian Tyree Henry), Sersi (Gemma Chan), and Kingo (Kumail Nanjiani), which could be a story for a potential Eternals 2.

Starfox’s MCU debut is big news for a number of reasons, and not just because of what he brings to the table. There’s also the matter of his link to Thanos. Needless to say, the two look nothing alike, so there are several lingering questions about how they can be related, and what this revelation says about Thanos’ backstory. Here’s how Starfox’s grand entrance in Eternals’ post-credits scene has retconned Thanos’ past, and how viewers can make sense of the change.

How Thanos Is Connected To The Eternals In Marvel Comics

Thanos and Starfox facing one another in Marvel Comics.

In Marvel Comics, it was established that thousands of years ago, the Eternals based on Earth decided to split up. Most elected to remain on the planet while a smaller group – led by an Eternal named A’lars – chose to take his people into outer space in search of a new home. As a result of their journey, they formed a colony on Saturn’s moon, Titan. From then on, they became known as the Titanian Eternals. While there, A’lars fathered two children: Starfox and Thanos. While the Titanian Eternals (including A’lars and Starfox) all look identical to humans, Thanos stood apart from everyone else with his purple skin and distinctive physical features. It’s since been explained that Thanos’ differences from the other members of his species is due to a genetic rarity that is known as the Deviant Syndrome. Somehow, Thanos was born with the Deviant gene, despite being an Eternal in every aspect but his looks. He’s the only known Eternal in Marvel Comics to possess this mutation.

Thanos' Backstory In The MCU (Before Eternals) Explained

It was revealed in Avengers: Infinity War that Thanos’ alien species died off long ago due to overpopulation and a lack of resources in the MCU’s history. Only one other Titan aside from Thanos has been namedropped prior to Eternals, and that was A’lars. During the scene on Vormir, Red Skull mentioned in the movie that he was Thanos’ father. As for what the MCU’s Titans actually looked like, that question hasn’t been answered on-screen. Since the only shot of the Titans in Infinity War was a far-off glimpse, it was difficult to say for sure. However, they didn’t seem to share his hulking physique or Skrull-like chin. And whether or not they had powers and physical capabilities similar to his was never made clear in Infinity War. All things considered, Infinity War left a great deal unsaid when it came to the MCU’s Titans.

How Eternals' Starfox Reveal Complicates Thanos' MCU History

Starfox smiles and floats in outer space in Avengers #232.

Eternals made big changes to what Infinity War established about Thanos and the Titans. In the movie, it was found out that the Celestials created the Eternals at a place called the World Forge. Apparently, each and every one of them is a synthetic being built by Celestial technology. The Celestials use them to find planets and plant seeds so that these worlds can lead to the births of new Celestials. Once their missions are completed, they’re brought back to the World Forge, where their memories are erased. Then, they’re sent off to start all over again.

Starfox showing up on the Domo and revealing that he’s Thanos’ brother (and an Eternal) means that like the comic character, the Mad Titan is a member of their race. That certainly complicates Thanos’ origin, since the villain was never thought to be a synthetic lifeform, but an organic being born and raised on Titan. There’s also the matter of his relationships with Harry Styles' Starfox and A’lars. If they’re synthetic lifeforms that were “made” rather than “born”, then how can any of them possibly be blood-related? Furthermore, the MCU has yet to offer an explanation on Starfox and Thanos’ physical differences, or if the Deviant Syndrome was responsible.

How Thanos Can Be An Eternal In The MCU

For now, it remains to be seen how Marvel will approach the Thanos connection and how it fits in with the lore surrounding the Eternals. One way the movies may make it work is by drawing inspiration from A’lars’ comic history. In the comic books, A’lars and Thanos’ mother, Sui-San, relied on science to populate their colony on Titan with new Eternals. If A’lars and Sui-San used their genetic material to create Thanos and Starfox, that could be the reason why the two are considered to be sons of A’lars in the MCU. If their efforts to genetically engineer Eternal children weren’t a flawless process, then it’s possible that one of their creations ended up with some genetic mutations. If that’s the case, that could be why Thanos looks so different to Harry Styles’ Starfox.

It’s worth noting that Thanos and Starfox being Eternals doesn’t mean that the same was true for everyone on the planet. If they were, that too would be an issue with Eternals’ Thanos retcon, as it’s hard to imagine all of these immortal, powerful beings just dying off. Instead, the Titanian Eternals may have lived amongst the people of Titan in the same way that Ikaris, Sersi, and all the others co-existed with humans for 7,000 years. If there were only a few Titanian Eternals to begin with, that would help explain Thanos and Starfox being the only ones who survived whatever tragedy that befell their homeworld. Hopefully, all of these new questions and mysteries about Thanos’ missing origin will be properly addressed when Starfox makes his next MCU appearance.

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