The X-Men Are Back—And They Might Break the Multiverse in Avengers: Doomsday

Why the X-Men Are in Avengers: Doomsday

(And How They Might Help—or Break—the MCU Multiverse)

Remember when Marvel made us stare at a lineup of empty chairs and we all lost our collective minds trying to figure out who was invited to the next multiversal mashup? Yeah… that wasn’t just for hype—it was the calm before the cosmic storm. Because Avengers: Doomsday is shaping up to be the wildest Marvel crossover yet, and the original Fox X-Men are crashing the MCU party in a big way.

But why are they here? What role do they actually play in the MCU’s biggest showdown? And how is all this even possible?

Let’s grab our Cloaks of Levitation and dig in.

The Multiverse Has No Bouncer

First things first—Marvel isn’t pulling any punches with Avengers: Doomsday. When they confirmed that OG actors from Fox’s X-Men universe are returning, the internet went full mutant meltdown. We’re talking Beast, Nightcrawler, Cyclops, Mystique, Magneto, and the GOAT himself, Professor Charles Xavier—and yes, played by the original cast. These aren't MCU variants in disguise or multiverse-adjacent lookalikes. These are the same actors, the same X-Men we grew up watching on grainy DVDs and midnight movie premieres.

So… why bring them in now?

Because things are getting messy in the multiverse. Ever since Doctor Strange in the Multiverse of Madness, Marvel has been laying the groundwork for a major cosmic collision: an incursion. It's when two universes start to overlap and—if left unchecked—they eventually implode or annihilate each other. Think of it like trying to copy and paste one entire timeline onto another. The result? Glitches, gravity chaos, and reality itself having a nervous breakdown.

The Fox X-Men universe and the MCU's Earth-616 are on a crash course, literally. This isn't just a cameo fest. This is canon-breaking, multiverse-shattering, fan-theory-confirming madness—and the X-Men are dead center in it. The walls are coming down, folks. And it all started with one unexpected hero falling through a crack in reality...

What's an Incursion Again?

If the word “incursion” sounds like it belongs in a sci-fi textbook, don’t worry—we’ve got you. An incursion, in the Marvel multiverse, is when two universes start to physically and temporally overlap. Imagine placing two Earths on top of each other like pancakes—only they’re both sizzling with nuclear-level energy, and the laws of physics start panicking. That’s an incursion.

Marvel introduced the concept pretty bluntly in Doctor Strange in the Multiverse of Madness, when Reed Richards of Earth-838 gave our Stephen Strange a little multiversal reality check: “Your arrival here confuses and destabilizes reality.” Translation? Every time someone jumps into a universe they don’t belong in, they leave a footprint—and enough footprints means the floor gives out.

The Marvels doubled down on that idea. When Dar-Benn used her quantum bands to rip reality open, she wasn’t just opening portals. She was destabilizing the fabric of the multiverse itself. Monica Rambeau, in her heroic moment, flew through the tear to seal it—but she didn’t come back. She landed somewhere else entirely. A reality that looks suspiciously like the Fox X-Men universe.

Enter: Kelsey Grammer’s Beast, confirming it’s not just a fun Easter egg. It’s the next big battleground. And now Monica’s very presence in their timeline? Yeah… it’s like leaving a lit TNT block in a wooden house. The longer she stays, the closer these universes get to total collapse.

Beast Knows Things

Don’t let the fuzzy blue fur and dry wit fool you—Beast is one of the smartest minds in the multiverse. Whether it’s quantum theory, mutant genetics, or advanced tech that Tony Stark would raise an eyebrow at, Hank McCoy is a scientific powerhouse. So when he finds Monica Rambeau unconscious in their world at the end of The Marvels, he doesn’t just see a lost traveler—he sees a cosmic problem waiting to go boom.

Here’s the kicker: the X-Men don’t have a TVA. They don’t have time branches or pruning sticks or Lokis giving them crash courses on sacred timelines. So unlike the Illuminati from Multiverse of Madness, who locked up Strange the second he stepped foot into their world, Beast’s crew did… nothing. They helped Monica. Which is great for Monica—but terrible for their universe.

You see, Monica is from Earth-616. And the more time she spends in the X-Men’s world, the more their reality starts to bend, stretch, and collapse under the weight of that contradiction. It’s Multiversal Physics 101: two timelines can’t hold the same mass for long.

Beast is likely the first to notice the gravitational anomalies and time fractures that signal an incursion is coming. And if he doesn’t act fast? These two universes are gonna collide like two Endgame portals trying to open in the same spot. Boom. Multiverse broken. Welcome to Avengers: Doomsday.

Xavier + Nightcrawler = Multiversal Uber?

Okay, here’s where it gets geeky in the best way. What if Nightcrawler—aka Kurt Wagner, teleportation legend—could be the key to sending Monica home? We know his powers let him bamf from point A to point B within a universe. But what if he could jump across universes?

That’s where Professor X comes in. If Charles can tap into Monica’s memories, he could project a vivid image of Earth-616 into Nightcrawler’s mind, giving him a precise mental target. That’s crucial, because Kurt typically needs to see or know where he’s going—or else risk teleporting into a wall. Yikes.

But even with a mental map, Nightcrawler’s powers have limits. He can't just bamf through dimensions. That’s where Beast might build a teleportation amplifier—a machine that boosts Nightcrawler’s range using Monica’s energy signature and some high-tech magic. This idea is straight out of the Secret Wars comics, where the Illuminati used a teleporting mutant named Manifold and a massive device to jump between dying realities.

So yeah, Beast builds it, Xavier maps it, and Nightcrawler jumps it. If this mutant dream team can pull it off, Monica goes home—and maybe, just maybe, they prevent Avengers: Doomsday. But if they fail? Well… let's just say they better start building that multiversal ark.

Wait, Is This the X-Men's Illuminati?

It might be. There are rumors swirling that Beast and Xavier could be part of their own version of the Illuminati, and that they’re building a multiversal defense force. If true, they’re probably already arguing with a multiverse-aware Dr. Doom (yes, that Doom—maybe played by RDJ?!) and trying to stop a full-blown incursion war.

The twist? Monica could be the equivalent of Vision from Infinity War—a walking key to a cosmic disaster. And everyone wants a piece of her.

X-Men Civil War?

Now imagine Magneto and Mystique joining the conversation. Not everyone’s gonna agree on how to deal with 616. And with Famke Janssen reportedly returning as Jean Grey, it could get messy.

Imagine this:

• Cyclops sides with Doom, believing war is the only option.
• Jean Grey joins Xavier, desperate to find a peaceful way.
• Magneto? He’s likely to take matters into his own metal-bending hands.
• Mystique? Don’t trust her for a second.

It’s X-Men vs. X-Men—with the multiverse at stake.

Will They Build the Ark?

Just like in Secret Wars (2015), some heroes might try to build an ark to survive the destruction of their universe. If the MCU follows this arc, we could see a superteam of brains—Beast, Xavier, Monica, Shuri, Smart Hulk, Reed Richards, Pym, Rocket, Vision, and more—trying to build the last escape hatch out of Doomsday.

All while others prepare for war.

So, Why Are the X-Men in Avengers: Doomsday?

• Monica fell into their universe, creating a ticking multiversal bomb.
• Beast and Xavier may try to send her back using tech, telepathy, and teleportation.
• Their presence sets off political, scientific, and emotional chain reactions that lead to war, fractures, and possibly a full-blown multiverse collapse.

The X-Men aren’t just cameos—they’re key players in the next era of Marvel’s saga. And honestly? We’re totally here for it.

Stick with Land of Geek Magazine for more wild multiverse theories, Marvel mayhem, and mutant madness! This party’s just getting started.

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