Warning: This post contains major spoilers for Avengers: Infinity War. If you don’t want to know details yet, click away now and come back here when you do!

You probably have a lot of thoughts about the ending of Avengers: Infinity War. Even though the conclusive turn of events is almost definitely going to be reversed, it was still a genuinely shocking moment. How many of us really thought Thanos was going to pull it off? With so many dying at his hand, by the time the literal dust settled it was hard to keep track of who had vanished. But it’s not those who disappeared fans should be worried about, it’s those who were left behind who are in far more danger, because Marvel just set up the original Avengers for a heroic—and permanent—goodbye in Avengers 4.

We saw five of the original Avengers survive Thanos’ grand extermination; Captain America, Iron Man, Black Widow, Bruce Banner, and Thor did not get snapped out of existence. And there’s almost a zero percent chance Hawkeye vanished off-screen, since it would be a total betrayal to have such important character meet his end without a proper farewell. In other words, all six original Avengers are still around.

…And there are six Infinity Stones.

If those pretty rocks gave Thanos the omnipotent ability to instantly wipe out half the universe, the only possible way to undo that is to gather all the stones too. But Thanos was already one of the most powerful beings in existence, a prerequisite for holding even one of the stones, let all of them, and it took him years and great personal sacrifice to gather the bunch. So what will the cost be for the mostly human Avengers to do that? And what will the cost be to use them?

It’s all but a guarantee the ending of Infinity War won’t stand, even if just from a business standpoint considering Spider-Man and Black Panther are getting sequels. Marvel obviously knows we know that. But they also know you can’t tell this story without true and lasting consequences. Which is why this “false” ending makes it seem likely that those who remain—a group that also includes War Machine, Rocket, Gamora, Okoye, and M’Baku—are the ones likely to really die trying to reverse things. That’s especially true of the original Avengers, who are the heart of the entire franchise, and whose story the MCU thus far has been principally devoted to telling.

Based on what we saw in the movie, it’s almost impossible to know what they will have to do to take those stones back from Thanos, if he even still has them. Infinity War‘s ending also saw the Mad Titan transported back to the unexplained plane of existence connected to the Soul Stone, where young Gamora was waiting for him, so there is enough mystery surrounding what he accomplished to make it hard to guess what is coming next.

That’s also exactly why it doesn’t seem like an accident that the six original Avengers survived. If they do get the stones back and activate their own version of the Infinity Gauntlet to snap everyone else back into existence, will it only demand a full-team mortal sacrifice?

Of course we must also consider an only partial-team sacrifice, as there have been recent talks of a Black Widow movie, not to mention the fact that Thor, as a god, may have the power to wield as stone or two. Nevertheless, we’re gearing up for an ending that’s bound to crush us in one way or another… but one that would also be amazing. What possible better ending could the greatest heroes get than making the greatest sacrifice for the greatest cause? And after a decade of having dubious stakes, Marvel would cap with the most epic conclusion ever.

And this doesn’t even get into specifically awful moments, like who will be sacrificed for the Soul Stone. Doctor Strange knew the only way to beat Thanos was to let him win, so long as Tony survived. But is this just gearing up to have him sacrifice himself later on, as he nearly did at the end of The Avengers? And perhaps in front of Steve Rogers, before—or after—they’ve properly patched things up?

The ending of Infinity War won’t stand, but it’s possible that by the end of Avengers 4, where we truly say goodbye to the original heroes of the MCU, we might wish it had.

What do you think? What is in store for the original Avengers? Give us your best theory in the comments below.

Images: Marvel

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