Avengers: Endgame introduced time travel to the Marvel Cinematic Universe, as Earth's Mightiest Heroes had no choice but to venture back to some of the most iconic moments in their history in search of the Infinity Stones. Using the Quantum Realm as an entry point, the Avengers visited 2012 New York, 2013 Asgard and 2014 Morag. On paper, these destinations seem like no-brainers, but based on a newly discovered Easter egg, they may not have been the only options.

An eagle-eyed Reddit user caught a detail in Endgame that may hint at a scrapped time-travel sequence. After the Avengers returned from their time heist, and mourned the loss of Black Widow, the team heads off to finish their new gauntlet and reverse Thanos' snap. At the same time, 2014 Nebula, who is posing as herself from 2023, uses the Quantum Tunnel to bring her father and his forces to the film's present day. A screen displaying the time-travel log indicates the years 2012, 2009 and 2988. While the first two dates have significant meaning to the MCU, it's the last one that has fans scratching their heads.

Whenever an MCU Easter egg like that surfaces, the first place to turn for clarity is the pages of Marvel comics. In the source material, the year 2988 doesn't have any significance, but there is an Earth-2988. That alternate reality debuted in What If? Vol. 2 #111, in which Wolverine becomes a Horseman of Apocalypse, eliminates most of the world's criminals and unites Earth against Apocalypse. This reality features alternate versions of Bruce Banner and Tony Stark.

Within the context of the MCU, Earth-2988 has seemingly no significance, which means directors Anthony and Joe Russo, and writers Christopher Markus and Stephen McFeely, probably didn't sneak that number in as an Easter egg for comics enthusiasts. So, if the source material is a bust, where else could the answers lie? Well, while some assumed 2988 was a year in the future, it very well might be one in the past.

The year 2988 B.C. may sound familiar to fans of Thor: The Dark World. As Odin explained, the first Convergence began in 2988 B.C., when the Dark Elf Malekith planned to use the Aether to send the Nine Realms into an eternity of darkness. During what became known as the First Battle of Svartalfheim, Odin's father Bor halted Malekith's plan, and sent the Dark Elves on the run. After their defeat, they entered suspended animation and would awake at the time the next Convergence began, which led to the events of The Dark World.

Given that the Avengers were searching for the Infinity Stones, traveling back to the ancient past to retrieve the Aether could have made for a quick-an-easy extraction using their modern technology. While this scenario was surely considered by the team at Marvel Studios, it made more sense for Thor's arc for him to travel to 2013 Asgard and share the scenes with his mother, Frigga, who put him back on the right path in time for the film's climax.

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Directed by Joe and Anthony Russo, Avengers: Endgame stars Robert Downey Jr. as Iron Man, Chris Evans as Captain America, Mark Ruffalo as Bruce Banner, Chris Hemsworth as Thor, Scarlett Johansson as Black Widow, Jeremy Renner as Hawkeye, Brie Larson as Captain Marvel, Paul Rudd as Ant-Man, Don Cheadle as War Machine, Karen Gillan as Nebula, Danai Gurira as Okoye and Bradley Cooper as Rocket, with Gwyneth Paltrow Pepper Potts, Jon Favreau as Happy Hogan, Benedict Wong as Wong, Tessa Thompson as Valkyrie and Josh Brolin as Thanos. The film is available on Digital HD, Blu-ray, and 4K UHD.

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