The name Cyclops is synonymous with the X-Men. As the team's best leader, he's led the X-Men through some harrowing situations, bringing them through battles with some of the most dangerous foes around and leading the mutant race during some very trying times. His time with the team has earned him a lot of friends- and enemies- and has shown what a great hero he can be.

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One of the most important X-Men on the team, his fellows have a lot riding on just how good he can be but there have been times when despite how hard he tries, he's let the team down. Whether it be through his actions or just some of his more unpleasant personality traits.

10 All Of The Times He's Left The Team

Uncanny X-Men 138 Cropped

For someone who is so defined by his time as an X-Man and is as devoted as Cyclops is to the mutant cause, he has left the team a lot. The first time was not long after he met the Jean Grey clone Madelyne Pryor, leaving the team to start a family with her. He would eventually become a superhero again but stay away from the team, leading X-Factor.

He'd leave again in the mid-90s, after Operation: Zero Tolerance when the X-Men lost Xavier's wealth and everything they owned, a time the team needed him the most. Cyclops has a tendency to abandon the team and it's never a good thing.

9 When He Decided To Form The X-Force

X-Force

As a leader of the reduced mutant race post-House Of M, Cyclops had to make some hard decisions. Mutants numbered in the scant hundreds and their enemies were moving in for the slaughter, ready to finally end the mutant race once for all. Knowing this, Cyclops and Wolverine gathered a team of mutants who had no qualms with killing and formed a new X-Force.

They were able to keep the team secret for a time but when the X-Men found out, they were very disappointed in Cyclops and Wolverine both, as most members of the team were anti-killing. Cyclops would disband the team but Wolverine would secretly keeping it going, working to protect mutantkind in his own way.

8 He Was Generally Kind Of Insufferable For Years

Classic X-Men 44 Cyclops

Cyclops took being the leader of the X-Men very seriously; besides his relationship with Jean Grey, it was pretty much the only thing he had in his life. It defined his personality pretty much completely and it made him into a pretty insufferable person for a long time. While his emphasis on training and discipline was a good thing for the team, he was never not that person even in his off time.

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Most of the other members of the team found him unbelievably stuffy and overbearing, wishing he would lighten up and have a little fun in his life. The fact that he held himself to such standards made his teammates wish that he could take things easy, if only for himself.

7 The Terrorist Years Were A Bad Time For All Involved

Bendis Uncanny X-Men

Post-Avengers Vs X-Men, Cyclops escaped from prison and teamed up with other outlaw mutants, like Emma Frost, Magik, and Magneto. Together, they would recruit new students and become a more proactive group, causing trouble, fighting the Avengers, and generally making mutants look bad to the general public. This distressed the X-Men who didn't team with him because it made their lives that much harder.

Mutants had just went through one of the most harrowing times of their existence and for one of the most important mutants of them all to start acting like an edgy teenager and causing trouble made things that much harder for the mutant race.

6 Getting With Emma Frost Was Questionable At First

jean grey catches emma frost and cyclops in bed together

Cyclops and Jean Grey's marriage got really weird after the affair with Apocalypse and the Twelve. Cyclops had lived with Apocalypse in his head, changing the way he looked at the world, and Jean Grey was becoming more and more powerful, going the power of the Phoenix. They grew away from each other and Emma Frost was there for him. They would start to have a psychic affair and when Jean died, they would get together.

While Cyclops and Emma's relationship would end up being a good thing for both of them, at first his teammates were pretty angry at him. No one trusted Emma and they looked at it as a betrayal of Jean's memory.

5 The Way He Abandoned Madelyne Pryor

Marvel Comics' Madelyne Pryor, the Goblin Queen

Mister Sinister created Madelyne Pryor because he wanted a child born of Cyclops and Jean Grey's genetics, a child that would give him an edge against Apocalypse in case Sinister ever needed to go against the ancient mutant. For a time, their relationship was good but then Jean Grey showed up and things changed drastically.

Cyclops basically abandoned Madelyne for Jean and this drove her crazy. Eventually, she would take on the guise of the Goblin Queen and try to destroy New York City. All of Madelyne's sins and all of the misery she caused the X-Men are all Cyclops's fault.

4 When He Ordered Oya, Who Was Only A Teenager, To Kill

Oya CBR

A brand new Hellfire Club reared its ugly head when the X-Men were living in San Fransisco, one made of rich, genius children. Using the Club's resources and their own villainous smarts, they attacked the X-Men while they were attending a museum opening. Quickly dispatching X-Men like Magneto, Namor, and Emma Frost, the Club were about to start executing hostages.

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Cyclops, seeing no other alternatives, ordered Oya, a young mutant girl with ice and fire powers, to fight off the Hellfire Club and she did so, killing all of their henchmen. This move by Cyclops showed the X-Men just how far Cyclops would go and many of them didn't like what they saw.

3 When He Split The Mutant Race

X-Men Schism Cyclops Vs Wolverine Marvel

After ordering Oya to kill, Wolverine and Cyclops came to blows, with Wolverine not liking Cyclops using children to kill and Cyclops basically blaming the whole thing him because Wolverine was not there. The Hellfire Club would attack again, using a powerful new Sentinel design to almost kill every mutant on Utopia, which Wolverine was able to stop. Afterwards, mutants chose sides and what was left of the race split up.

Cyclops could have prevented all of this if he hadn't doubled down on his already bad decision and made things personal with Wolverine. Instead, he let his emotions get away from him and it would cost everyone in the future.

2 When He Killed Professor X

Cyclops kills Xavier in Avengers Vs X-Men from Marvel Comics

Cyclops and the X-Men would end up battling the Avengers over the Phoenix Force. He and four other X-Men would become hosts for the Force and would, predictably, start being overwhelmed by the power, fighting amongst themselves. Eventually, the Avengers would bring Xavier into the mix, hoping he and Cyclops's relationship and Xavier's power would allow them to defeat the mutant.

Unfortunately, Cyclops was too far gone and ended up killing Xavier. This move would color the way the X-Men saw him afterwards, a terrible tragedy that wouldn't be fixed for years.

1 The Time That He Almost Destroyed The World By Becoming The Dark Phoenix

CYCLOPS DARK PHOENIX

After killing Xavier, Cyclops would completely give himself over to the Phoenix, becoming Dark Phoenix and battling the combined forces of the X-Men and the Avengers. With the powers of the Dark Phoenix, he was a threat to the entire world and it took everything the heroes had to stop him. He would ultimately be proven right in his supposition that the Phoenix would save mutants, as Hope Summers and Scarlet Witch were able to combine their power and Scarlet Witch's reignite the mutant gene.

While it ended well for mutants, this was the biggest let down the X-Men ever suffered because of Cyclops- no one thought he would every try and destroy the world after all he had done to save it.

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