Marvel has provided more evidence that Thanos is still alive after the events of Avengers: Endgame. The third act of Avengers: Endgame saw the Avengers triumph in their battle against Thanos, when Tony Stark snapped his fingers and erased Thanos and his army from existence. There's been intense speculation as to whether or not Thanos actually died, though, and whether he could potentially return. Now, Marvel has further fuelled fan speculation with the publication of The Art of Marvel Studios' Avengers: Endgame, a book of concept art and exclusive interviews, which contains two important clues regarding what happened to Thanos at the end of Endgame.

At the heart of all this is the simple question of what really happened in the two snaps — the one in Avengers: Infinity War, and the one in Avengers: Endgame. The fact that Stephen Strange could see behind the snap, when according to Doctor Strange a sorcerer cannot see beyond death, supports the idea that the snaps didn't really kill at all; the same theory is also supported by a deleted scene from Avengers: Endgame, in which the Ancient One said the Infinity Stones could not reverse death - but can still undo the snap.

Related: Avengers: Endgame Proves Hela Is More Powerful Than Thanos

Addressing the idea of reversing the snap, and why that is different to bringing back Black Widow, Marvel Studios co-president Louis D'Esposito explains that the Infinity Stones cannot reverse death. "When someone dies, you cannot bring them back," he explains in the Avengers: Endgame art book. "It's not like when Thanos snapped his fingers. You can reverse that." This fits perfectly with the Ancient One's claims, confirming that Marvel don't believe the first snap really killed anyone at all. A second comment, from executive producer Trinh Tran, supports the idea that Tony Stark's Thanos-destroying snap is a mirror-image of Avengers: Infinity War. "[Tony chooses] to snap his finger and blip Thanos and his minions away to save the universe," she observes. The word "blip" is the one Marvel used to refer to the snap in Spider-Man: Far From Home.

Tony Stark snaps in Avengers Endgame

The question is, then, what did the two snaps actually do? The physical effect saw bodies, clothing, spacecraft, and objects being held by snap victims transformed into dust, and that wasn't just a cool special effect; the lighting in the post-snap world is deliberately darkened, reflecting the fact a large number of particulates had been introduced into the atmosphere, and are preventing some of the sun's radiation reaching the Earth. The lighting briefly changes after the Hulk's snap, in the scene where the Hulk looks at the birds in the tree, indicating that this additional dust has been extracted from the atmosphere again. It's more difficult to guess what happened to people's souls, though — proven to exist in the MCU by Black Panther's Ancestral Plane. One theory is that the souls were transported to the Quantum Realm, explaining a mysterious flood of energy at the moment Thanos snapped his fingers.

Whatever happened in the snaps, one thing is clear: they could be reversed. It took the power of the Infinity Gauntlet to undo Thanos' snap, but it might be easier to reverse Tony Stark's. After all, Thanos affected the entire universe, whereas Tony's was geographically limited and erased a far smaller number of beings and objects from existence. It's entirely possible that, somewhere in the universe, some alien race had the ability to undo the snaps on a limited level - Doctor Strange wouldn't see that, because he was focused only on events on Earth and Titan. That means there's even a theoretical possibility Thanos could come back, despite what happened in Avengers: Endgame.

More: Marvel Reveals Thanos Has Different Names In Infinity War & Endgame

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