WARNING: The following contains spoilers for Uncanny X-Men #1 by Ed Brisson, Matthew Rosenberg, Kelly Thompson, Mahmud Asrar, Rachelle Rosenberg and Joe Caramagna, in stores now.

In Uncanny X-Men #1, Marvel's team of mutants once again finds itself under attack on all fronts. Not only are they dealing with inexplicable, catclysmic events, they also clash with a mob of uncontrollable Multiple Men -- and that's only in the main story. Uncanny X-Men #1 is a massive book, and in addition to its main story, the issue boasts three short stories that introduce other plot threads to be picked up at some point in the future.

One of these storylines may involve a threat the X-Men haven't faced before, one that's closely associated with Iron Man, which is why it's so surprising to see it pop-up here: The Extremis virus appears to be on the X-Men's horizon.

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In "What Tomorrow Brings," Jean Grey and Storm find a rare instance of quiet time to enjoy a hot beverage in a coffee shop. But before they can even sit down, a man with glowing eyes and fiery fists comes crashing through the roof. He shoots a beam of energy at the two women, and then one of the baristas also turns of them, shooting energy from her mouth. Then, the entire crowd inside the coffee shop attacks Jean and Storm, each and every one of them with their eyes glowing bright, seemingly operating as some sort of hive mind.

While the word "Extremis" isn't explicitly mentioned in the story, it sure looks like that's what has taken over the people. After all, when it was first created by Aldrich Killian, the Extremis virus granted its hosts many properties such as super-strength and fire-breathing.

Since its first appearance, the Extremis virus has gone through a few iterations, the most recent of which, version 3.0, was modified by Tony Stark's brother Arno Stark. What we see in Uncanny X-Men #1 is closer to the original Extremis, but it still may be a new concoction.

Of course, there's always the possibility that whatever's attacking Jean and Storm is something else entirely. But from what we've seen so far, it's more likely that this old Iron Man threat has resurfaced to take on the X-Men. And if it can take over people so easily, the mutant team might soon have an entire army of super-powered humans to deal with.

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