Over decades of X-Men comics, several plot threads have become iconic. The X-Men fight for those who hate and fear them, take on gigantic mutant-killing sentinels, and live in a mansion filled with young mutants. While they're rarely connected with Marvel's sci-fi line-up, the team also became known for their constant time travel adventures.

The X-Men are no strangers to braving dystopian futures or alternative versions of the past. Sometimes, they simply want to find their way back home. Other times, some X-Men take it upon themselves to rewrite reality by influencing past events. For better or worse, the X-Men's time traveling shenanigans in Days of Future Past and House of X/Powers of X changed everything readers knew before.

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10 Excalibur: True Friends

X-Men: True Friends #1 cover

Excalibur is best known for being a British superhero team, which introduces a unique atmosphere for the X-Men book. Excalibur: True Friends took that setting and made it even more interesting by taking Kitty Pryde and Rachel Summers back to World War II in England.

Excalibur: True Friends challenges the very notion of time-travel stories, because it questions the very narrative behind Days of Future Past. Kitty plans assassinations in Berlin to take out Nazi officials. Meanwhile, Rachel, a young Queen Elizabeth, and Wolverine force her to consider the changes she would make to the future. It raises interesting questions and helps to further Kitty's relationship with Rachel.

9 Battle Of The Atom

Battle of the Atom

Most time travel stories involve only one group traveling. The X-Men take a trip to the future or a villain comes back to haunt them. Battle of the Atom was unique for doing both. The time-displaced X-Men were '60s superheroes in the present time, and a group of future X-Men villains came back to the present to change their utopia into a dystopia.

Battle of the Atom's interesting concept twisted other X-Men time travel stories. In a vacuum, it was far from perfect, but in context, it challenged everything that the X-Men typically believed. The past, present, and future were at odds, and the ever-terrifying future actually appeared to be a comfortable place for once.

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8 X-Men: Messiah War

X-Force, Cable, and Messiah War

At its core, X-Men: Messiah War is the epitome of time travel stories. After taking baby Hope into the future to protect her in Messiah CompleX, Cable returns with an older Hope. Hope's personality starts to show, and she gets a moment in the spotlight as she works to survive.

X-Force, Cable, and Hope face unintended time travel when they face off against Stryfe in X-Men: Messiah War. With Hope acting as the Mutant Messiah, the actual emotion of hope is present throughout the event. X-Force's desperation is palpable, and the overarching goal of saving mutantkind hangs over them all. It's an excellent story that offers insight into the pain the mutants were feeling after the Decimation.

7 The Adventures Of Cyclops And Phoenix

Further Adventures of Cyclops and Phoenix vs Apocalypse

In X-Factor #1 (created by Bob Layton, Jackson Guice, Josef Rubinstein, Petra Scotese, Max Scheele, and Glynis Oliver), Cyclops made the decision to abandon his wife and child. The Adventures of Cyclops and Phoenix couldn't save his relationship with Madelyne Pryor, but it gave him the opportunity to raise his son.

The Adventures of Cyclops and Phoenix bridges the gap between Nathan Summers' birth and his evolution into Cable. It's also been hailed as one of the best Jean Grey and Cyclops comics. Cyclops and Jean take a trip to the future, where they raise their son Nathan and face off against an alien society. The world-building is brilliant, and the book creates a solid redemptive moment for Cyclops.

6 Inferno

split image: Moira in Inferno, Cyclops and Jean battle in the Dark Phoenix Saga and Emma Frost separates Scott and Jean

Inferno doesn't initially appear to be a time-travel story. However, it reveals the truth behind Omega Sentinel's existence. Having experienced the same type of reset as Moira MacTaggert, Omega Sentinel is desperate to ensure that the AI win the war against the mutants and humanity. After all, in her experience, the mutants always win.

The history of Orchis was clouded during the Krakoan era, but this revelation made absolute sense. Instead of characters being left to wrestle with the idea of mutants always losing, Inferno actually questions that narrative. It reveals Moira's flaws, while also turning Omega Sentinel into a more comprehensible character.

5 Cable (2021)

Kid Cable holding a gun

Cable is a character inherently grounded in time travel. While he was born to Cyclops and Madelyne Pryor in the X-Men's typical timeline, he has spent his entire life traveling through time. Cable (2021) followed a younger version of the character as he reckoned with the present — and his future — while trying to cope with his existence.

Cable grants the titular character a childhood, while also letting him engage in his true heroic nature. Like Adventures of Cyclops and Phoenix before it, Cable fills the gap in Cable's past. An inexperienced Nathan Summers must grapple with child theft, Stryfe, and even his older self.

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4 Here Comes Tomorrow

Wolverine killed by the Beast (Sublime) in "Here Comes Tomorrow."

The Age of Apocalypse version of Beast is a dark character, but the Here Comes Tomorrow variant puts Dark Beast to shame. Taking place a century after New X-Men, Here Comes Tomorrow puts an end to Grant Morrison's run when Beast destroys everything. Desperate for destruction and death, this monstrous Beast is crueler than the Krakoan Beast.

Here Comes Tomorrow feels like a classic X-Men story, and it has the double duty of wrapping up all of Morrison's plot threads. Every detail in their run is properly concluded, while hammering the very theme of endless repetition home.

3 Legion Quest

Legion on fire from Marvel Comics

After going back in time to change Professor X's history, Legion accidentally causes the Age of Apocalypse event. Legion Quest created one of the most iconic periods in X-Men history, and the lead-up was as engaging as it was realistic. By causing his father's death, Legion created the perfect story.

Ambition alone made Legion Quest brilliant. Few books are willing to upend an entire line, but this X-Men comic accepted that risk, and given Age of Apocalypse remains one of the most renowned X-Men events of all time, their gamble cleared paid off.

2 House Of X / Powers Of X

Wolverine and Moira MacTaggert confronting the Librarian in Moira's Sixth Life from Marvel Comics

While House of X may not delve too much into time travel, Powers of X does. Taking place 100 and 1,000 years in the future, Powers of X presents multiple different dystopian futures. The glimpses at the future offer a look into the overarching theme: That the mutants always lose, but that there is still hope.

It is easy to empathize with Moira MacTaggert since she is constantly jolted back to the past after experiencing such horrific futures. The story also helps to set up Nimrod as a present day threat, despite the fact he lost to a group of children in New X-Men: Academy X. House of X/Power of X also plants several important seeds for future X-Men events like Inferno, Sins of Sinister, and Fall of X.

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1 Days Of Future Past

x men days of future past

It's genuinely challenging to fit a story as complete as Days of Future Past into two comic issues. Yet, that's exactly what Uncanny X-Men does. It creates a harrowing future with detailed horror and tremendous stakes. At the same time, it weaves that storyline into the "present day" Uncanny X-Men plot. Days of Future Past forever hanged the X-Men's world and comic book history.

With a direct look into their future, the X-Men became forever aware of the consequences that could befall them should they fail to achieve peace between mutants and humanity. If they failed to protect the mutants, it could lead to complete devastation. The consequences in Days of Future Past are long-lasting and directly led to the undying reliance of time travel tropes in the X-Men comics. The story also introduced Rachel Summers, Cyclops and Jean Grey's daughter, who'd play a significant role in future comics.