The epic conclusion of Avengers: Infinity War has spawned near-endless fan theories about how the remaining Marvel heroes will defeat Thanos in Avengers: Endgame. Some of those point to Earth's Mightiest Heroes using time travel, or to the timely arrival of Captain Marvel as a ringer to help in the final battle. There's certainly evidence to support those time-travel scenarios, with time vortexes within the Quantum Realm serving as a potential means. Certainly, the prominence of Paul Rudd's Scott Lang in the trailers adds credence to the suggestions that Ant-Man may prove key to the ultimate defeat of the Mad Titan.

But one not-quite-safe-for-work theory proposes that Scott's role could go beyond time-travel assistance, and stead be far more graphic. It's been dubbed the "Thanus Theory," and it's exactly what you think. Yes, as the theory goes, Ant-Man will kill the Mad Titan by ... shrinking down and crawling up his butt, then expanding until he breaks through, ultimately killing Thanos.

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We truly are in the rear-endgame now.

The Thanus Theory has spawned countless memes, Vox has traced it all the way back to 2017. In the Marvel Studios subreddit, Cafetorialoca created a thread in July 2017 titled "Worst ways they can stop Thanos ..." The most up-voted theory suggested the Hulk be put in an Ant-Man suit before shrinking and entering Thanos' mouth, not unlike Drax's attempts to kill an inter-dimensional monster in Guardians of the Galaxy Vol. 2, although this theory calls for the Hulk to expand once he reaches Thanos' nether regions.

Ant-Man in Avengers: Endgame

The idea of Thanos being destroyed from the inside arose in December 2017 as a Reddit user, maxwellthebeach, uploaded a photo of Ant-Man on the Mad Titan's ear. The suggestion was that Ant-Man would enter Thanos' head through his ear canal before expanding, and ultimately exploding his head. This theory, however, was not without its holes, as some users pointed out that Thanos is invulnerable, and that Scott Lang would just be crushed within his skull before oozing out of his ears.

They do seem to have a point. In Marvel Comics' The Ultimates, Monica Rambeau entered Thanos' skull in her energy form in an attempt to kill him. She was successful in only wounding him, however, as Thanos was able to regain control of his brain. One of the users in the thread posited that the only way for Ant-Man to kill Thanos from the inside would be to utilize the "Squirrel Girl method," in which Ant-Man crawls up his butt before rapidly expanding.

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The theory was once again brought to light following the release of Avengers: Infinity War, from which Ant-Man was conspicuously absent. A Twitter user sent a tweet in April 2018, shortly after the blockbuster hit theaters, suggesting the real reason Ant-Man didn't appear was that Marvel Studios had caught wind of the Thanus Theory. That tweet eventually made its way to Paul Rudd, who was asked about it during his press tour for Ant-Man and the Wasp. "I don't know," he replied, skeptically. "I almost think it's a question for Thanos, because if there's one thing we learned from Infinity War, it's that Thanos can take a lot of punishment."

As memes for the Thanus Theory have flown around the internet over the past month, some have pointed out a rather large (ahem) crack in the theory, which falls in line with Rudd's own doubts. Thanos so thoroughly beat the Hulk that he refused to come out for the remaining two and a half hours of the film. He also knocked out Captain America and Black Panther with a single punch each, all without the use of the Infinity Stones. With Thanos being the physical specimen that he is, he could simply stop Ant-Man from killing him from the inside by crushing Ant-Man with his purple, muscular glutes.

The Avengers had a chance to stop Thanos in the nick of time, but Thor didn't go for the head. But could it be that the best chance for Earth's Mightiest Heroes to stop the Mad Titan once and for all is with an Ant-Man suppository?

Directed by Anthony and Joe Russo, Avengers: Endgame stars Robert Downey Jr., Chris Evans, Mark Ruffalo, Chris Hemsworth, Scarlett Johansson, Jeremy Renner, Don Cheadle, Paul Rudd, Brie Larson, Karen Gillan, Danai Gurira, Benedict Wong, Jon Favreau and Bradley Cooper, with Gwyneth Paltrow and Josh Brolin. The film arrives April 26.