WARNING: The following contains spoilers for X-Men/Fantastic Four #4 by Chip Zdarsky, Terry Dodson, Rachel Dodson, Ranson Getty, Laura Martin, and VC's Joe Caramagna, on sale now.

The mutant race has been faced with countless challenges from a world that hates and fears them. Even when they aren't actively being hunted, their allies can accidentally cause conflicts that lead to more and more problems for the mutants. After a recent team-up brought the X-Men and Fantastic Four together, Mister Fantastic inadvertently created something that could've been devastating to mutantkind. And while it may have been stopped, it may hurt relations between the X-Men and the FF permanently.

In X-Men/Fantastic Four #4, Charles Xavier and Magneto revealed to Reed Richards that he'd accidentally created a very effective mutant cure while trying to hide Franklin Richards' mutation from the world. After that revelation, Xavier took drastic measures to ensure that Reed forgot about making that cure and locked it away from his mind.

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While traveling to New York City alongside Franklin Richards, Xavier and Magneto casually excuse themselves from the rest of the Fantastic Four to confront Reed Richards. They reveal that Beast's research into Franklin's mutation has led to the discovery that the Code-X, the device Reed developed to hide Franklin's mutation from others, had an unintended side-effect: it was partially responsible for Franklin's dwindling power levels since the device also accidentally suppressed the mutant gene instead of just disguising it. Although he knew about the possibility of this, Reed considered it a low-enough risk to still use it on his son. In essence, Mister Fantastic just created a new (and more effective) mutant cure without even realizing it.

The prospect of a mutant cure has always been a threat to the X-Men and their way of life, as it could be used offensively to wipe out entire generations of mutants. At worst, it could even fall into the hands of the X-Men's enemies and be used as a weapon to help wipe out mutants once and for all. Although Reed is quick to apologize just for the concept alone and is genuinely shocked by the side-effect of the device, Xavier and Magneto decide a more forceful response is required. That's why Xavier uses his telepathy to openly probe Reed's mind and find all the information connected to the Code-X. Because Reed crossed a line against "all mutants," Xavier even puts a mental block on the information, ensuring that Reed can never access that information again.

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Xavier Reed Richards

Although it's a major invasion on Xavier's part, Xavier describes the act as a mercy for a "man who doesn't understand the consequences of his actions," and reminds Reed that this potential cure is a threat to the mutant race's very right to survive, including Franklin. Xavier even resists the temptation to simply wipe the memory of the confrontation from Reed's mind either, as he would have done during the days when Xavier and Reed were among the Illuminati and let the moment linger as both a lesson and a warning. The pair leave Reed in his lab after destroying the Code-X device, with Reed not even resisting their arguments.

With Reed left fully aware of their actions, he now knows what could happen if he fully enrages the X-Men. But it's unlikely that Reed will just forget this confrontation. This could potentially jeopardize any connection between Reed and the rest of the X-Men, who could always use more allies given the number of enemies that have either resurfaced or risen against the X-Men in recent months. Alternatively, it could be seen as a humbling of Reed, which could explain why he doesn't try to argue in his defense when Xavier and Magneto face him.

In an attempt to shield his son from the realities of growing up, Reed created one of the greatest threats to the resurgence of the mutant race. While Reed turns his wild ideas into potentially world-changing inventions all of the time, this particular piece of information could have destabilized the still tenuous place in the world that the X-Men have carved out for themselves with Krakoa. It's also a stern warning from Xavier and Magneto about not making enemies of mutants.

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