One of the X-Men's longest-held core values has always been to preserve life, mutant and human, friend or foe. Even in Johnathan Hickman's reimagined Dawn of X landscape, where the mutant-held Krakoa finally has some legitimate geopolitical clout, the governing Quiet Council still made "Kill No Man" one of three overarching mutant laws.

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But that doesn't mean that mankind has always been safe in the presence of the X-Men. In some cases, the humans deserved it; in others, bystanders became mutant-issued collateral damage. Here are 10 of the worst things Mutants have done to regular humans.

10 Archangel's Penchant for Executing Anti-Mutant Extremists

Close encounters with Archangel are not advisable for members of far-right fringe groups. in 1988's X-Factor #34, while locked in a hand-to-hand grapple with Cameron Hodge, Hodge questioned Archangel's stomach for the kill. One panel later, Hodge is suddenly headless, decapitated by the cold edge of Archangel's organic steel wing.

Fast forward to 2010's Second Coming event, when the X-Men were outnumbered in a scrap with the Purifiers. For expediency's sake, Archangel rained down steel feather missiles on the anti-mutant zealots before cutting Rev. William Stryker clean in half with the whoosh of his wings.

9 Magneto's Involvement in the JFK Assassination

In the X-Men movie continuity, if you can even call it that, 20th Century Fox dropped a huge conspiracy theory nugget in the marketing run-up to the release of 2014's X-Men: Days of Future Past by positing that Magneto was involved in the JFK assassination in 1963.

Using the 50th anniversary of the JFK assassination as an opportunity to market a super-hero movie, a black-and-white faux-Zapruder film, dubbed The Bent Bullet, shows a still frame of someone that looks like Michael Fassbender's Magneto standing along the infamous Grassy Knoll as a motorcade drives by. According to the promo video (which can hardly be considered canon, but here we are), Erik Lenscherr was arrested and tried secretly for first-degree murder and conspiracy to assassinate the 35th President of the United States of America.

8 Fetus X's Attempted Sororicide

Charles Xavier tried to kill his twin sister in New X-Men #121 with a toddler-sized psi-burst while they were still sharing space in their mom's womb. How's that for making future family gatherings awkward? The psi-burst that left baby Cassandra stillborn should technically register as mutant-on-mutant crime, but imagine the trauma the whole experience wrought on the kiddos' poor human mother, Sharon Xavier.

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The fetal Royal Rumble going on inside her tummy caused Sharon to miscarry Cassandra, or at least that's what everyone thought at the time. The baby's discarded body mutated in the sewers for decades. Eventually, Cassandra Nova became one of the X-Men's fiercest foes, albeit one who, in the face, had a certain uncanny resemblance to her more famous brother.

7 Wolverine's First Blood

In 2001's Origin miniseries, a young James Howlett walked in on an argument between his dad and a former employee, Thomas Logan. Logan's murder of John Howlett triggered little James' bone claws to extend for the first time, and, in a fit of rage, James ran Logan through. Only then did Wolverine learn that he, too, was a Logan.

As for his mother Elizabeth, this particular trauma was compounded even further by the miniseries' reference to three parallel scars running down her back, hinting at an older sibling of James' who also had claws.

6 Wolverine's Family Tragedy, Continued

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If mistakenly killing one nuclear family member wasn't enough, decades later, Wolverine would unknowingly finish off five of his illegitimate children in an elaborate plot put into motion by a hooded group calling themselves the Red Right Hand. The Red Right Hand was made up of the loved ones of people whom Wolverine had killed, its members intent on revenge throughout an early run in Wolverine Vol. 4.

The Red Right Hand recruited five warriors dubbed the "Mongrels" to their cause, but knew none of them stood a chance against Wolverine in battle. When Wolverine dispatched them all and confronted the cult leaders, they were already dead, after poisoning themselves. In a sadistic posthumous video, the Red Right Hand told Logan that he had just killed five of his kids. The episode devastated Logan, who predictably retreated to live alone in the woods for a while.

5 Dark Beast's Killing Spree

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Dark Beast occupies the Earth-295 timeline, a world in which Charles Xavier never forms the X-Men and Apocalypse eventually takes over America. Without Xavier's guidance, this Beast is an unmitigated monster but remains a scientific genius. In 1996's X-Men Unlimited #10, Dark Beast had been living in regular Beast's Earth-616 timeline for some time but hatched a new plan to come out of the shadows and assume the real Beast's life in his timeline.

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Dark Beast worked to get close to the McCoy family, their old parish priest, Hank McCoy's old girlfriend and others who knew him as a youth, to get useful information out of them so he could continue the ruse. After Dark Beast gathered the information he needed, he killed them all, not only to tie up loose ends but also so that he could use the anger it produced in the real Beast to his advantage in the coming fight, which Dark Beast won.

4 That Time Namor Flooded Wakanda

Namor is one of the world's oldest mutants and committed one of his worst atrocities in the New Avengers 2013 run. See, the Sub-Mariner sided with the X-Men in that version of X-Men vs. the Avengers, and while on a field trip to the moon with Cyclops, Emma Frost, Magik, and Colossus, all five come in contact with the Phoenix Force.

In the ensuing conflict between the X-Men and the Avengers, the Phoenix-endowed Namor (now with red Phoenix pants!) brought the fight to Wakanda by weaponizing a lake and emptying it onto the advanced African civilization, trashing Black Panther's kingdom and killing thousands of innocent inhabitants.

3 Magneto's Golden Gate Bridge Attack

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Returning to the X-Men's clumsy cinematic continuity, Magneto's attack on the Golden Gate Bridge in 2006's X-Men: The Last Stand featured some pretty large scale collateral damage.

Summoning his unparalleled mastery over the earth's electromagnetic field while hovering over stacks of backed up traffic, the Golden Gate first begins to sway, then rock, before Magneto rips it from the sea and drops it atop a nearby military installation. And what did the commuters do to deserve the early demise at the hands of the Master of Magnetism? They just so happened to be in front of Magneto in all that bridge traffic.

2 Captain Kate Pryde's newfound militarism

In Marauders #1 of the Dawn of X relaunch, Kitty Pryde insists on being called Kate, and her fighting moves are all grown up, too. In a skirmish on the other side of a Krakoan gateway to Russia, a swashbuckling Captain Kate front-kicks the rifle right out of the hands of one anonymous Russian goon and pops him one in the kneecap with his gun.

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But she makes the reader feel these idiots' pain when she phases that same rifle into the legs of two other hapless henchmen. When it solidifies, all the Russians can do is collapse and writhe in pain. Turns out, she's the perfect X-Pirate.

1 The Creation of Onslaught

The Onslaught saga was set into motion by none other than Charles Xavier. It's one of several glaring black marks on the wise professor's overall record. Xavier was so wrought with anger after Magneto zapped all the adamantium off of Wolverine's skeleton in X-Men Vol. 2 #25 that he probed Magneto's mind and shut it down. A byproduct of the melding of Magneto's mind with Charles Xavier's was the creation of the all-powerful combo-mutant Onslaught.

Onslaught's immense power drew a response from not only the X-Men but also from the Avengers and the Fantastic Four, whose members sacrificed themselves to kill Onslaught. Leaving the earth's human population without the protection provided by those two teams, it could be argued, is about the bleakest outcome for humans on a planet occupied by as many supervillains as Earth-616. But, of course, both teams were "reborn" in 1996-97's Heroes Reborn story arc, because, comics.

NEXT: 5 Magneto Costumes We Loved (& 5 He Should Never Wear Again)