Everybody looking forward to Avengers 4 is expecting the surviving heroes to take the fight to Thanos and hopefully undo all the devastation he caused with his infamous finger-snap, but what if he's not the real villain? When considered that Avengers: Infinity War was essentially Thanos' story, with the villain sitting peacefully on a farm at the end, his mission to balance out life in the universe successfully accomplished, will Avengers 4 really feature Thanos as its main villain?

For all intents and purposes, Thanos won. To have the Avengers regroup, undo the snap and defeat Thanos in Avengers 4 would almost be too easy. Marvel Studios aren't always in the business of tying off their movies with neat little bows, after all. Whether it's SHIELD being dismantled at the end of Captain America: The Winter Soldier, Asgard being destroyed at the end of Thor: Ragnarok, Scott Lang being trapped in the Quantum Realm in Ant-Man and the Wasp, and yes, Thanos wiping out half of all life at the close of Avengers: Infinity War - Marvel don't always end their movies with events unfolding as blockbuster-trained audiences expect, or with the status quo being maintained.

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Could the shocking twist in Avengers 4 be that Thanos isn't ultimately the final villain the Avengers face? If not, will they actually have to turn to him in their hour of need? The most likely scenario is that Thanos is still the villain, but a few fan theories and some Marvel comics history give some other fun possibilities.

Avengers 4 Is Infinity War: Part 2... Is Thanos The Villain?

Thanos Says Avengers Assemble

The ending of Avengers: Infinity War left the remaining heroes (along with Captain Marvel) a task that is perhaps greater than the threat of Thanos. First, the surviving heroes - being the original Avengers, alongside War Machine, Okoye, Nebula, Rocket, Hawkeye (or perhaps he should be called Ronin now), and Ant-Man - have to deal with losing half of all the universe. The fact that so many of the lives lost belonged to friends and allies puts a personal spin on the Avengers' desire to undo what Thanos wrought, and it will likely be their first priority. Especially considering that Thanos has retired to his peaceful farm life, meaning he won't be an immediate threat, safe in thinking his work is done.

The fact that Avengers 4's plot appears to have some basis in time travel, the Avengers could take the fight to Thanos in the past - although, as anyone familiar with time travel will attest, meddling with the past can only inspire the butterfly effect to royally screw the future. Upon returning to the present, our heroes may well have to ally with Thanos to either undo their debilitating effect on the future, or combat some new threat to the future.

Read More: There's No Way Avengers 4's Time Travel Will Make Sense

Alternatively, Thanos' actions could draw some new all-powerful, malevolent being to the fore - something with knowledge of the Infinity Stones, attracted by their combined usage for what we assume is the first time. After all, Thanos' use of his only Infinity Gauntlet irreparably broke it, so his capacity to use the Stones is done with. He won't be as much of a threat as a tired old farmer than when he was with all the Stones at his command.

Page 2 of 3: Could the Avengers Team-Up With Thanos?

Thanos Avengers Team-up

Thanos Has Teamed Up With The Avengers In The Comics

The source material provided by Marvel Comics has given us a few instances where Thanos has had to ally with the universe's heroes. Starting with the combined efforts of Thanos and cosmic hero Adam Warlock (alongside his Infinity Watch) to defeat a powerful being called the Magus, who attempted to replace all the beings in existence with evil doppelgangers of his own creation, the Mad Titan has had periods of time where he operated as an anti-hero to protect the cosmos.

Later, when Thor apparently went insane, Thanos was recruited to help combat the rogue God of Thunder by the Silver Surfer, alongside Doctor Strange, Adam Warlock and the Infinity Watch. He was later personally thanked by Odin and Thor for his help. He also once saved Spider-Man and the Surfer from a malicious supercomputer called Quasimodo.

When the heroes of Earth discovered that a parallel universe was making incursions into their own reality, endangering both, Thanos even set out with Namor and the rest of their Cabal to destroy the opposing universe. Thanos also ended his alliance with Annihilus and his Annihilation Wave, freeing Galactus from his dastardly machinations, in order to preserve existence. When taken into account that one of the rumored titles of Avengers 4 is Avengers: Annihilation, its easy to imagine that elements of that storyline could be featured - although characters like Annihilus and Galactus are currently caught up in the Disney/Fox merger, and thus likely won't be allowed to be used for some time.

Related: Black Panther Shuri Could Be Key To HOW The Dead Heroes Return

There are so many storylines to draw from that it wouldn't be too much of a surprise to see the Avengers team up with their hated foe on-screen.

Potential Villains: The Mind Stone

A recent fan theory on Reddit posited that the Mind Stone is more pivotal to the plot of the Avengers movies than fans realize. Infamously, it was the last ingot for Thanos to achieve, and audiences thought our heroes were successful in preventing him from getting to it - when the Scarlet Witch heartbreakingly destroyed it whilst it was centered in her beloved Vision’s head.

Of course, Thanos managed to use his newly-acquired Time Stone to simply rewind the event, undoing Vision’s heroic sacrifice and ripping the Mind Stone right out of his skull. Going forward into Avengers 4, we could see the Mind Stone taking more precautions to defend itself - thus tying in with the other prevalent theory, that the Stone is sentient, and has been - with no less than malicious intent - ever since we unknowingly first saw it makes its debut as Loki’s scepter in The Avengers.

The Mind Stone appears to be at the center of almost every conflict the Avengers have faced since their inception. When the Avengers capture Loki and begin analyzing his scepter (with the Mind Stone within it), the weapon itself appears to be fostering discord among the nascent team, leading them to be more combative with each other than they should reasonably be. In Avengers: Age of Ultron, Banner and Stark discover that the scepter is “thinking”. The Mind Stone gave Witch her powers, which she initially uses on Stark - bestowing on him a dark prophecy of his teammates dying, that ultimately drives him to use the scepter to create Ultron. And, of course, Ultron (created by the mind stone) is the murderbot that went on to try and delete all of humanity.

Related: How Avengers 4 Can Resolve Age of Ultron's Dreams

It certainly appears that the longer people are subjected to the Mind Stone, the more they want to fight, destroy or kill. Like Thor says after Vision’s creation, “I've had a vision. A whirlpool that sucks in all hope of life, and at its center is that,” pointing to the stone in Vision’s head. Vision himself seems to be unaffected by the seemingly malevolent Stone - as Banner points out in Avengers: Infinity War, Vision’s mind is “a complex series of overlays,” but that doesn’t exclude the possibility that, say, everybody lost their minds a little bit during Captain America: Civil War and fought each other, thanks to their proximity to him and it?

What if Scarlet Witch temporarily destroying the Mind Stone causes it to reach a new height of sentience and autonomy in Avengers 4, becoming the final threat it's been building to be all this time? Is it possible it could take over Thanos’ mind completely - after all, he may have only become the ‘Mad’ Titan after the scepter first came into his possession before the first Avengers movie. An all-powerful Mind Stone controlling someone as powerful as Thanos could lead to the Avengers attempting to free the poor, Mad Titan, and possibly team up with him to defeat it immediately afterward.

Page 3 of 3: The Celestials and Eternity War

Power Stone Celestials

The Celestials

It was established in Guardians of the Galaxy that the ancient race of all-powerful beings known as the Celestials were the first ones to find and utilize the Infinity Stones. They were all-powerful and extremely destructive with their use of them, especially in one brief flashback that shows a Celestial using the Power Stone to wipe out an entire civilization “like wheat in a field.” The Celestials in that skyscraper-sized form have yet to be seen alive and kicking in the present Marvel Cinematic Universe - Kurt Russell’s Ego aside, who comes in a slightly different form to his brethren - the remnants of one of their severed heads has been used as a mining colony known as Knowhere.

It wouldn’t be too much of a stretch to imagine that the rest of the Celestials have been lying dormant somewhere, and Thanos’ use of "their" Infinity Stones would be a catalyst to bringing them back, searching for either vengeance against Thanos or the simple desire to take back their property. If this happens, it would open up a threat to the MCU hitherto unseen by its heroes. Ego was enough of a challenge for the combined strength of the Guardians in Guardians of the Galaxy Vol. 2, meaning a whole group of Celestials could lead the Avengers to do something desperate to fight them - like teaming up with Thanos, perhaps?

Related: All The Ways Avengers 4 Will End the MCU As We Know It

In the current run of Avengers comics by Jason Aaron, the Celestials made a comeback in a big way, leading a new roster of Earth’s Mightiest Heroes caught up in a battle between Celestials and Dark Celestials, who had been infected by a disease-like race of bugs called the Horde. It took Ghost Rider possessing a Celestial, Iron Man in a Jaeger-style version of his armor and She-Hulk and Thor drinking the Blood of Ymir to become Kaiju-sized in order to successfully defeat the Dark Celestials.

The heroes realized that the potential for super-beings had been inserted into mankind’s DNA by the original Celestial - the Progenitor - in order to one day combat the Horde for them, billions of years later. If that doesn’t sound like an ambitious way to wrap up this era of the MCU, who knows what is. If the Celestials do pop up in Avengers 4, it's doubtful they’ll go through the creation-of-man plot points, but it does set up some intriguing potential storylines for the future if they are fully introduced as a present threat next year.

Eternity

Thanos and Eternity

The omnipotent, abstract entity known as Eternity is actually the physical manifestation of the Marvel universe, presenting itself as an anthropomorphic being with the swirling cosmos in place of its skin. Depicted coming into play in some of the loftier Marvel comics when the universe is at stake, Eternity has stepped in every now and then to assist the heroes residing within itself. Notable occasions include when Thanos had previously collected the Infinity Gems in the comics, or later, the equally powerful MacGuffin known as the ‘Heart of the Universe’.

Eternity still has yet to make an appearance in the (relatively) grounded MCU, but as we are now dealing with the fate of the cosmos thanks to Thanos’ actions in Avengers: Infinity War, there is the capacity for the cosmic entity to make an appearance.

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Thanos’ actions with the Infinity Gauntlet have upset the natural order of the universe, and in the comics, a precedent has been set for Eternity to be a champion of said natural order - going so far as to explain to every living being in existence that Galactus, the world-devourer, is part of it. It’s easy to suppose that should Eternity exist within the MCU, it’d have a problem with Thanos using the Infinity Stones to wipe out half of all life, just like it did in the comics. Should Eternity show up in Avengers 4 - which is doubtful, as the idea is a little too abstract for mainstream audiences who can just about buy a talking raccoon and his best friend, a tree - it’d be as an antagonist to Thanos.

It’s also possible that Eternity would not be able to distinguish between Thanos and Earth’s heroes, as Doctor Strange, Iron Man, and Vision have been guilty of using Infinity Stones on-screen too. What if it decided that the safest way to protect creation from the Stones is to extinguish all those who went after them? That’d lead to another potentially awe-inspiring third act where Earth’s Mightiest ally with Thanos to fight Eternity itself!

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The fact that this theory would be so shocking is a big indicator that it's probably not the case. While Marvel Studios has kept a mostly tight lid on Avengers 4, there's still been a few leaks, and something as massive as this would be almost impossible to hide, especially when marketing kicks in. Even so, it's not outside the realm of possibility, and if they do pull it off, would be one of the most exciting twists in movie history.

Next: Avengers 4: Every Update You Need To Know

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