The X-Men will soon be joining the MCU. After the dizzying highs and terrible lows of the 20th Century Fox years, fans are ready for a new take of Marvel's Merry Mutants on the big screen. The MCU promises more accurate costumes, at the very least, and fans are excited about the possibilities of crossovers with other MCU characters. This being the X-Men, there's a lot of fertile story ground to cover as well.

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That said, there are some stories that X-Men fans don't want to see adapted. There's a wide variety of reasons for this. The X-Men are a very storied franchise, but Marvel Studios might not be able to do justice to some of their best tales.

10 X Of Swords Is Too Drawn Out

Several X-Men come down from the sky brandishing swords from Marvel Comics

X Of Swords was the first major crossover of the Krakoa era. The twenty-two-part story ran through every X-Men title and three bookend comics. Pitting the island's champions against the mutants of Arakko, the sister island of Krakoa that has resided in Otherworld for millennia, and the demonic hordes of Amenth, it's the very definition of a bloated, low-stakes event.

X Of Swords was a very hit-or-miss story. Some parts were excellent. Others weren't. The first half of the story was long and drawn out, while the second half had some good moments but was still lackluster. It's also a very complicated book, so leaving it in the comics is really a favor for MCU fans.

9 The Mutant Massacre Is Way Outside The MCU Wheelhouse

Wolverine ravaged from a fight in Marvel Comics

The Mutant Massacre is a mid-80s tale that crossed over through Uncanny X-Men, X-Factor, Thor, and Power Pack. Written By Chris Claremont, Walt Simonson, and Louise Simonson with art by John Romita Jr., Walt Simonson, Sal Buscema, and Jon Bogdanove, the story saw Mr. Sinister's Marauders attack the Morlock Tunnels, killing every mutant down there as the heroes tried to stop them.

This story is rather important to the X-Men mythos, but it's also something the MCU should never attempt. Marvel Studios isn't the best at serious stories like this, and it really doesn't fit the quippy style that is the bread and butter of so many MCU films.

8 X-Men: Mutant Genesis Is A Classic, But No One Needs To See It On The Big Screen

Cyclops and Wolverine lead the X-Men against Magneto from Marvel Comics

X-Men: Mutant Genesis, by writer Chris Claremont and artist Jim Lee, redefined the X-Men for the '90s. Not only did it introduce the fan-favorite Blue Team line-up that every fan can identify in their sleep, but it's also the end of Claremont's seventeen-year run on the X-Men. It's a great story that X-Men fans love, but its time is thirty years in the past.

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Fans want more from the X-Men than just the old '90s Blue Team, and the ones who don't are getting X-Men '97 on Disney+ already. Mutant Genesis will always be a top-tier X-Men tale, but that doesn't mean it needs to be adapted.

7 Everyone Should Stop Trying To Adapt The Dark Phoenix Saga

Dark Phoenix Grins evilly over the unconscious bodies of Storm and Colossus

The Dark Phoenix Saga is in the running for the greatest Marvel comic ever. Writer Chris Claremont and artist/co-plotter John Byrne's masterpiece about the transformation of Jean Grey into the monstrous Dark Phoenix, and the X-Men's desperate attempts to stop her, is often considered the X-Men story that fans think they want to see, but the last two adaptations prove otherwise.

The problem Fox had was that they didn't want to do the actual saga. This isn't a problem that Marvel Studios would have, since they have no problem building things long-term, but it's a matter of trust. Could the MCU pull off a dark, emotional epic like The Dark Phoenix Saga without bungling it? Better not to attempt it.

6 The Age Of Apocalypse Is An Alternate Universe The MCU Shouldn't Visit

Wolverine leads the new X-Men in Age of Apocalypse

There are few Marvel alternate universes more beloved than The Age Of Apocalypse. The mid-90s alternate universe epic spanned eleven series and two bookends, clocking in at a massive forty-four parts. Taking place in an alternate universe where Xavier was killed before he formed the X-Men and Apocalypse took over the US, it's a beloved tale that is completely wrong for the MCU.

The MCU may be branching into the multiverse, but they need to stay away from AoA. It's not an MCU friendly story, and even if it was, its massive length would preclude it since it would take so long to tell the story right.

5 Astonishing X-Men: Gifted Just Isn't That Interesting

Astonishing X-Men charging into battle in Marvel Comics

After the revolutionary nature of New X-Men, Astonishing X-Men: Gifted changed the game for the X-Men franchise. Written by Joss Whedon with art by John Cassady, the story reintroduced Kate Pryde to the X-Men mythos and pit the team against alien enemy Ord just as a mutant cure became available on the market.

Gifted was a safe nostalgia-influenced take on the X-Men. Fans were wild for it when it started, but it hasn't aged well, especially considering Whedon's history of sexual misconduct. It needs to be left back in the 2000s where it belongs, especially if it would benefit Whedon in any way.

4 "Here Comes Tomorrow" Is Too Cool For The MCU

X-Men Here Comes Tomorrow 1

Grant Morrison's time at Marvel was short but full of brilliant stories. Their New X-Men run is top-notch, with their final tale, "Here Comes Tomorrow," wrapping up plot threads from throughout their three years writing the X-Men. Joined by X-Men artist extraordinaire Marc Silvestri, the story takes place a hundred years in the future, as the X-Men retrieve the Phoenix Egg from the moon.

When it's stolen by the Beast of the Apocalypse, it's up to Wolverine and the X-Men of the future to save the day as Jean Grey returns under the command of their most hated enemy. Like many Morrison stories, it's full of concepts that MCU fans just aren't ready for. It's brilliant, but too much so for the MCU.

3 House Of X/Powers Of X Wouldn't Be Done Justice By The MCU

House of X/Powers of X, depicting Professor X, Magneto and Jean Gray walking through a Krakoa Gate.

House Of X/Powers Of X is a must-read X-Men story. Written by Jonathan Hickman with art by Pepe Larraz and R.B. Silva, the two books introduced the Krakoan status quo. The story of the two books introduced all kinds of great new concepts to the X-Men mythos and brought the X-Men back to prominence after years of editorially enforced stagnation.

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The biggest problem with adapting HoX/PoX is trusting Marvel Studios to pull everything in the book off. There's a lot of high-concept sci-fi, sly social commentary, and epic action that is out of the MCU wheelhouse.

2 E Is For Extinction Is A Bit Too Much Morrison For The MCU

New X-Men cover from Marvel Comics with art by Frank Quitely

Grant Morrison's opening salvo on New X-Men was "E Is For Extinction." With art by frequent collaborator Frank Quitely, it's among the greatest X-Men stories of all time. When Wolverine and Cyclops discover a rogue Master Mold after a mutant rescue, a series of events unfold that result in a mutant massacre of epic proportions and a new villain with unbelievable ties to the team.

"E Is For Extinction" is Morrison to its core. Morrison's sensibility doesn't fit the MCU's style, and the story goes in some directions that the more casual fans of Marvel Studios aren't going to enjoy very much.

1 God Loves, Man Kills Is Too Serious For The MCU

Marvel Comics' X-Men God Loves Man Kills Cover by Brent Anderson

God Loves, Man Kills, by writer Chris Claremont and artist Brent Anderson, is a stone-cold classic, combining great X-Men action with biting social commentary. It's for that reason that Marvel Studios should stay far away from it. The story of the X-Men teaming with Magneto to stop mutant murders by Reverend Stryker and the Purifiers isn't MCU material.

God Loves, Man Kills is a story that doesn't flinch from calling out the hypocrisy of organized religion, which is something Marvel Studios just wouldn't do. Even as woke as the MCU pretends to be, Disney would never allow a story this critical of organized religion.

NEXT: 10 Ways The X-Men Broke Their Own Rules