Warning: The following contains major spoilers for House of X #5, by Jonathan Hickman, Pepe Larraz, Marte Gracia, VC's Clayton Cowles and Tom Muller, on sale now.

In House of X #5 , some of the X-Men's greatest villains take up Charles Xavier's invitation to join him on Krakoa. The X-Men's Sage says that there are 20 in "the first wave" of villains, and, sure enough, the end of the issue sees 20 new villains ally themselves with Krakoa for the first time.

While Magneto and Mister Sinister had already joined up with Xavier in some capacity or another, a huge swath of villains were officially welcomed onto Krakoa at the end of this issue. While they've all tangled with the X-Men in one capacity or another, some of these villains are merely antagonists, while others are truly evil mutants. Now, CBR is taking a look at all of these X-foes to see which ones really are the absolute worst.

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21. Marrow

Marrow vs Wolverine

As a former X-Man herself, Marrow's inclusion among the group of villains is almost peculiar. The former Morlock with bony protrusions she can wield like weapons certainly has her anger problems, which she's used as an aggressive member of the X-Men and X-Force.

She has fallen on society's bad side a time or two before, but she comes across as more sympathetic than outright villainous. While she may have started out bad, her time as a hero is far more memorable.

20. Random

Random X-Factor

As one of the most '90s characters in the Marvel Universe, the bandana-and-sunglasses-wearing Random was always more of an anti-hero than a true villain.

Created by Peter David and Joe Quesada in X-Factor, Random was a child who appeared older and favored personal profit over any kind of ideology. He even worked with the titular team on the side of the good guys when the price was right, so he's ultimately not that much of a bad guy, no matter how hard he tries to seem like one.

19. Astra

Astra X-Men

Touting herself to be one of the original members of the Brotherhood of Evil Mutants, Astra is one of the deepest cuts on the list in terms of obscurity. Most of what readers know about her from the comics involve her relationship with Magneto and her creation of his clone, Joseph, but the fact that she created the clone to embody Magneto's best parts at a time when he was outright villainous makes her cause a lot more sympathetic than others on the list.

Still, she also created an evil version of Josepeh and tricked him into attacking the X-Men in one of her few appearances.

18. Forearm

Forearm wields swords in his four arms in Marvel Comics

As a member of the terrorist organization the Mutant Liberation Front, Forearm pushes the evil-meter closer into the red. The super strong mutant with four arms genuinely believed in the MLF's revolutionary cause.

However, during Dani Moonstar's time undercover with the group, he showed the X-Man brotherly-affection while often serving as a voice of reason. Having twice the arms may make him look twice as tough, but on the inside he's really a big softie.

17. Callisto

The eye-patched sometimes-leader of the Morlocks is one of the most morally grey mutants on the list. The Morlocks often sought to secede from conflict and just wanted to hide from a world that hated and feared them.

Callisto would often make their cause more militant in her efforts to make the misshapen mutants stand up for themselves, but she was far from the worst leader the Morlocks had. At the very least she sincerely saw the group as a family, and it makes her efforts to defend them that much more justifiable.

16. Frenzy

There's no doubt that a member of a group called the Alliance of Evil would merit a firm ranking on the list, and Frenzy was no exception. The super strong brawler found her way from the Alliance of Evil to the Acolytes during her time as a super-villain. However, she wins a few morality points for making an effort at being a hero by joining the X-Men. Her impulsive and rash decisions would frequently get her and her allies in trouble, however, and she never really got a defining moral moment to break out of the mold she started in.

15. Lady Mastermind

Lady Mastermind

Like Marrow, Lady Mastermind is another former X-Man in the group of villains presented here. Unlike Marrow, Lady Mastermind not only first appeared as a villain, but later betrayed the team after her tenure serving them.

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She may not be as evil as her father, the Mastermind who served in the original Brotherhood of Evil Mutants, but she shared her father's ability for mental manipulation and wielded it toward similarly atrocious ends.

14. Animax

Animax

Animax is both one of the newest and most obscure characters in House of X #5. She has the uncanny mutant ability to create and control rampaging monsters from her genetic makeup.

She only appeared briefly in  a few stories in which she goes to prison, discovers her powers, and then breaks out to seek revenge, the monster-making Animax presented very few redeeming qualities in the few stories in which she appeared

13. Mentallo

As a petty crook rarely even involved with the X-Men or mutant politics himself, Mentallo proves that the X-Men's invitation toward villainous mutants did not extend solely to those they dealt with personally.

As a low level telepath who often sought personal fortune over anything else, Mentallo palled around with the likes of such high level villains as  M.O.D.O.K. Much like other mercenaries on the list Mentallo is just looking to earn a quick buck, but his history of doing so on the side of good is pretty slim.

12. Daken

Daken Wolverine

Wolverine's son shares almost none of his father's principles. Daken is a borderline sociopath, willing to wield his claws to kill someone as likely as he use to use his pheromone-manipulation to control their mind.

He has a long and interesting history behind him, but once you take into account that he's over years old the fact that he perpetually acts like a selfish teenager with daddy issues doesn't bode well for his morality.

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11. WILDSIDE

Wildside makes his move

Wildside is another member of the Mutant Liberation Front. While he might have the claws and agility of a Wolverine-esque brawler, the villain also has hallucinatory powers and has even been able to make his creations seem real.

As a craven opportunist, Wildside has even helped out anti-mutant efforts to stop the Legacy Virus from being cured and singed up with the Weapon X Program to do its dirty work.

10. Mesmero

Mesmero

Screwing with the very essence of a person's mind is always a messed up thing to do, and it's pretty much all that Mesmero does. The mutant hypnotist has been menacing the X-Men since the team's earliest days, and throughout all those years he has frequently screwed with the very identity of characters like Polaris.

He eventually formed his own Brotherhood of Evil Mutants, hypnotizing innocents like Magma into his cause, and the fact that he so often targets women specifically makes the super creep that much the worse.

9. Sebastian Shaw

Sebastian Shaw glowing with energy in Generation Hope

While Sebastian Shaw is set to appear in Marvel's upcoming Excalibur relaunch, Shaw has been a quiet mover-and-shaker within the Marvel Universe for years.

As the frequent leader of the Hellfire Club, Shaw was involved in some of the worst events in X-Men history. With the mutant power to grow stronger with each blow he takes, he's also more than a match for most in a physical one-on-one fight.

8. Black Tom Cassidy

With his power to channel energy through wood, Black Tom Cassidy is an Irish villain who originally cut his teeth manipulating the unstoppable Juggernaut before the pair became the best of friends.

When he wasn't fighting his brother Banshee, he also raised and brainwashed his own niece, Siryn, to help him rob banks. You don't get a name like "Black Tom" with a pure soul, and this roustabout future X-Force member is no exception.

7. Masque

While other members of the Morlocks come across as a lot more sympathetic, Masque is just plain vile. Masque's power centers on the ability to physically alter the appearance of others, and he used the ability to make many of the Morlocks more monstrous than they already were.

While there could potentially have been helpful and convalescent applications for Masque's power, the only use he ever put them toward were making the world an uglier place.

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6. Exodus

Exodus holding members of the X-Men in his hand

While he originally played second fiddle to Magneto while serving as the Master of Magnetism's Acolyte, Exodus more than made a name for himself as a major play amid X-Men villainy.

Empowered with an assortment of powers, with everything from super strength to telepathy to energy blasts, Exodus doesn't show up much, but disaster usually follows in this Omega-Level mutant's wake.

5. Emplate

 Emplate in Marvel comics

There was no period of X-Men history left ignored when it came to drawing from different eras for villains. Emplate primarily served as an antagonist in the Generation X comics of the '90s. As essentially a vampire who feeds on the bone marrow of his victims (and gains their powers temporarily if they are a mutant), Emplate does not have a powerset that lends him toward heroics.

While he's fought the X-Men on a few occasions, his story intrinsically ties in with that of his sibling Monet, who has been in the spotlight in House of X a few times already.

4. Selene

Selene standing in front of a wall of skulls

Emplate is not the only vampire worth a spot on the list, and the villain Selene fits the archetype even more. The Black Queen of the Hellfire club suffers all the same moral consequences as the Black King Sebastian Shaw, while her powerset lends her the same intrinsic antagonism as Empath.

She's never shown a shred of sympathetic motivation, and is perhaps best known for raising an army of the dead to wreak havoc on the world in the "X-Necrosha" crossover, which makes her one of the worst villains on the list.

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3. Azazel

Azazel X-Men

The Marvel Universe has more than its fair share of demons and devils, but the X-Men's most hellish regular villain is Azazel.

Most known for being Nightcrawler's father, Azazel earns his place in this band of mutants for being one of the Neyaphem, an ancient group of mutants with hellish appearances.

2. Apocalypse

house-of-x-apocalypse-header

Front and center in the climax of the comic, Apocalypse receives more attention than any of his fellows and for very good reason. The millennia-old mutant mastermind behind several attempts to ravage the world with conflict and violence proves without a doubt that the X-Men were willing to set their personal differences aside when looking for allies. Apocalypse is never a throw-away villain and is always at the center of major multi-issue arcs that lead to crossovers and disaster time and again.

Still, he doesn't quite get the top spot for the baddest of the bad because however mistaken he may be, Apocalypse is at least attempting to help the world. His twisted social-Darwinism is psychotic and unjustifiable, to be sure, but he seems sincerely committed to the belief that it could make the world a better place. Say what you will about the tenets of "only the strongest should survive," but at least there's a logic to his madness.

1. Gorgon

gorgon

As far as an ethos goes, you really can't get worse than "everyone should die because Death is great," which is Gorgon's usual modus operandi. Gorgon is barely an X-Men villain, having spent most of his time torturing Wolverine. However, he quickly grew beyond even that role and became a major threat with a terrifying presence.

At an early age, the super-genius Gorgon developed a mathematical formula to prove the existence of God, but never forgave Him for his existence. After murdering his family as a child , Gorgon then founded a terrorist death cult before he was even a legal adult, and his career as a villain just kept getting worse. Eventually he took over the death-worshiping ninjas of the Hand and HYDRA and harassed Marvel heroes ever since. There's absolutely zero redeeming qualities or sympathetic motivations on Gorgon's side, and the only only result of his beliefs inflicted on the world is mass murder and extinction.

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