One of the most powerful mutant groups from the X-Men universe is the Summers family, which has continually grown over the years to include alternate timeline daughters, long-lost brothers, sons from the future, and even evil clones.

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With such an interesting collection of powered heroes with generally terrible upbringings, it often comes as no surprise that members of the Summers family occasionally do very terrible things. While the worst things are often done with the best intentions, and occasionally happen outside of their control, we decided to take a look at a few awful things done by the Summers clan.

10 CYCLOPS ABANDONED HIS FAMILY

Cyclops Madelyn Pryor

It's hard to believe the Summers family ever went any further than Scott Summers and his brothers Alex and Gabriel, considering Scott's abandonment of his first attempt at a family following the death of Jean Grey during the Dark Phoenix Saga.

Scott married Madelyne Pryor, who resembled and was later revealed to be a clone of Jean Grey, and the two had a baby boy. Then Jean Grey returned to life, and Scott abandoned Madelyne and his child for his former love. Pryor would go on to become the Goblin Queen and attempt to sacrifice her son to bring Hell to Earth, so she clearly took it well.

9 CABLE ALMOST DESTROYED THE AVENGERS

As for Scott and Madelyne's child, he didn't fare too well either. Nathan Summers was infected with a Techno-Organic virus by Apocalypse and sent 2000 years into the future to survive. He would return to the present as the militaristic mutant known as Cable, and continue fighting to prevent the terrible future he grew up in.

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One one of his missions to save the future, he was forced to take down the Avengers in order to save the life of his adoptive daughter Hope Summers. Cable systematically took out the Avengers one-by-one and would have wiped them out if it wasn't for the intervention of Cyclops and Hope.

8 RACHEL HUNTED MUTANTS AS A HOUND

Rachel Summers hails from an alternate timeline and grew up in the "Days of Future Past" era where mutants were hunted to extinction and survivors kept in camps by Sentinels. Rachel's upbringing alone could have turned her to a dark fate, though she still became a trusted and valuable member of the X-men and the Summers family when she was exiled in the present day.

Before Rachel's joined the X-Men, she had been abused and brainwashed at the hands of the cybernetic human Ahab, which transformed her into a mutant-hunting Hound. However, her psychic abilities created a link between her and her mutant victims, which ultimately allowed her to turn on her handlers and shake off her Hound programming, though the trauma she suffered remains.

7 CYCLOPS CREATED A KILL SQUAD

X-23-X-Force

Scott Summers has always been a leader of the X-Men, and there was a time when he had also become the leader of almost the entire mutant race when they were facing extinction and living on the island of Utopia. After the success of assembling a new team of X-Force during the "Messiah Complex" event, Cyclops secretly re-assembled the team to pro-actively take out upcoming threats.

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While the morality of operating a kill squad in secret from the rest of the X-Men was obviously called out, it was Cyclops' disregard for his team's well being that made this one of his worst moments. Things like asking X-23 to be his private assassin when Logan brought her to the X-Mansion specifically to get away from that kind of life.

6 STRYFE RELEASED THE LEGACY VIRUS

Stryfe from the X-Men comics

When Nathan Summers was sent to the future to survive his T/O virus, a future version of Rachel Summers known as Mother Askani decided to clone the child in case he didn't survive. However, that clone was kidnapped as an infant and raised by Apocalypse, creating the ongoing threat known as Stryfe.

Following a vicious battle with Cable that revealed their previously unknown relationship to Cyclops and Jean Grey, Stryfe's full plan was revealed when a vial he had traded to Mister Sinister was opened, releasing the deadly mutant-killing Legacy Virus Stryfe had brought back from the future with him.

5 CYCLOPS INFECTED SKRULLS WITH THE LEGACY VIRUS

While most strains of the Legacy Virus were eventually cured, samples remained of either mutated strains or newly created versions of the disease. During the Secret Invasion event, the Skrulls attempted to invade San Francisco and the X-Men.

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As the X-Men battle with the Skrull and their army of Super-Skrulls, Cyclops is forced to employ his secret weapon; a modified strain of the Legacy Virus designed to infect Skrulls instead of mutants. When the Skrull ships start crashing and troops exhibit symptoms, they self-destruct instead of risk spreading the virus to other Skrulls. X-Men win, technically.

4 HAVOK TRIED TO UNLEASH MOTHERVINE

Havok and his Brotherhood looking at floating screens

Alex Summers/Havok has had a rough history and been the victim of brainwashing quite a few times. So when the AXIS event inverted his personality and unleashed his evil side, fans assumed he would quickly switch back again without much trouble.

However, he and Emma Frost (dealing with the recent death of Scott) teamed up with Bastion and Miss Sinister in an attempt to unleash the Mothervine virus, which would have either triggered secondary mutations in mutants or killed them and left the survivors under mind control. Thankfully Alex was stopped and reverted back to his original personality.

3 VULCAN TOOK OVER THE SHI'AR EMPIRE

Gabriel Summers/Vulcan was the long-lost brother of Scott and Alex who had been erased from their memory by Professor Xavier following Gabriel's "death" on a mission with an early team of X-Men. When Gabriel awoke and returned to Earth, he exposed Xavier's lies before heading to the stars to confront his dark origins with the Shi'ar Empire.

RELATED: X-Men: 10 Things Fans Should Know About Vulcan, The Third Summers Brother

Once there he began a conquest of the Shi'ar Empire that resulted in him marrying the royal sister Deathbird and then killing Emperor D'Ken to take over the Empire. During this coup of the Empire, he would also murder his father Christopher Summers/Corsair, who he blamed for his upbringing as a slave by the Shi'ar.

2 JEAN ERADICATED THE D'BARI

Jean Grey would eventually marry into the Summers family officially, but that marriage would only come after the events of the iconic Dark Phoenix Saga. Technically the version of Jean that became the Phoenix was revealed to be a body created by the Phoenix Force, but for all intents and purposes, it was Jean Grey.

And that Jean Grey would become tainted by Mastermind and the Hellfire Club and succumb to the corruption of its own power to become the Dark Phoenix. As Dark Phoenix, she would consume the star of the D'Bari solar system, wiping out planets and the entirety of the alien D'Bari race. She would later commit suicide instead of allowing Dark Phoenix to take over again, though the "real" Jean would soon return.

1 CYCLOPS KILLED PROFESSOR X

Cyclops and Xavier

The Summers family has had quite a few encounters with the Phoenix Force after its possession of Jean Grey. It would later bond with Rachel Summers on multiple occasions, and more recently, it would possess Hope Summers and the Phoenix Five during Avengers vs. X-Men.

While the Force was mostly under control when separated among five hosts, eventually Cyclops would be corrupted by its full cosmic power and become the Dark Phoenix. While battling with his mentor Charles Xavier, Scott would unleash his power and kill the founder of the X-Men.

NEXT: X-Men: 10 Worst Things Professor X Has Ever Done