Nightmare Fuel / X-Men

• Children of the Vault #3 truly shows how horrifically powerful the titular Children are. Cable executes a plan that turns an army of Orchis Mark IV and Stark Sentinels on their city. To add to that the Orchis Forge is unleashing blasts on the city strong enough to tear apart a planet. The Children are winning. The only reason why Cable and Bishop come out on top is by playing it smarter.
• In the New X-Men, Cassandra Nova, Professor Xavier's psychotic twin sister, commits genocide on a whim and smiles after she is done, which the 16 million mutants killed in Genosha by her Sentinels learned the hard way. Later, while trapped in stasis at the X-Mansion, she takes over Xavier's body while he is with Beast in Nova's holding chamber, brutally mind-rapes Beast to such an extent that he starts bleeding, and mentally forces the mutant student Barnell to savagely beat Beast to a pulp with a baseball bat. All while smiling eerily, with menacing red eyes to boot.
• The reason for Storm's severe claustrophobia: When she was a little girl, a plane involved in the Suez Crisis dropped on her family's house, killing her parents instantly, and burying Ororo under the rubble, where she stayed for days... with her mother's mangled corpse right in front of her.
• Ichisumi◊ the Pestilence, a.k.a. one of Apocalypse's Horsemen. Her mutant power is to release an infestation of near omnivorous yume beetles stored within her own body by dislodging her jaw, spawning from her mouth in massive swarms either devouring or disfiguring her intended mark. She is also able to mentally link with them when they return to her as each and every individual being her colony consumes also imparts unto them; and subsequently upon their habitat/queen, much of the victims' memories. You think the power to control insects like Ant-Man's power is lame? Think again!
• Mountjoy is a rarely-seen mutant criminal from the future with a truly horrific power that combines The Assimilator with pure unleaded Body Horror. He can absorb other beings into himself, a process he refers to as a 'merger', and if he doesn't 'divest' the victim they are eventually digested, with Mountjoy gaining all their abilities. At one point he absorbs a normal woman, and as he proceeds to monologue to himself the woman's screaming face rises out of his head, followed by her arms briefly flailing from under his coat. He doesn't even pause in his monologuing, suggesting that this sort of Body Horror is just par for the course, and when the woman's face rises up again he just gives his forehead a little smack and smirks to himself while remarking that he "loves it when they struggle".
• For other Body Horror fuel, the Morlocks, the horribly deformed monster mutants lurking in the sewers of New York, and particularly their Evil Chancellor, Masque. His power is similar to that of the Tzimisce vampires of the Old World of Darkness, namely to magically twist flesh into whatever configurations he desires. In the comic where they kidnapped Kitty Pryde to force her to marry Caliban, it was revealed that most Morlocks are not born deformed: It's just policy that Masque gives new "recruits" new faces so they can never return to their old lives.
  • Masque's creatively villainous use of his powers was mostly implicit/told-not-shown throughout most of the Claremont run, but towards the end he wrote some stories where it became horribly explicit, and Masque used it to abuse female(?) Morlocks in really nauseating ways.
• Genosha, pre-Magneto. Imagine South African apartheid, only directed at mutants, ramped up to a thousand, and with a side of Mind Rape and Body Horror thrown in for good measure. No, seriously; mutants are kept as a Slave Race and forced to use their powers to the advantage of the formerly impoverished and politically impotent island nation. To do this, they are forcibly bonded into suits that allow their human masters to completely control their actions, reducing them to near-mindless puppets. Their human masters also recklessly conduct experiments in bio-engineering and augmentation in order to further refine the usefulness of their slaves, including running deliberate breeding programs.
• Mr. Sinister from the X-Men comics. Yeah, whatever about the name, he is a scary son of a bitch. It has a lot to do with various fears (Unmarked dangers, manipulators, telepaths... something that can fuck you up real bad but you have no idea that they could). And that use of psychology that is on par with Hannibal Lecter's. Shapeshifting, the fact that someone could be effectively controlling you or your life without you knowing. He can just seem like a different person thanks to mind tricks and perfect shapeshifting. Hello, Paranoia Fuel
  • One particular backup story from an issue of the reprint series Classic X-Men was particularly chilling. The young Scott Summers (Cyclops) grows up alone and bullied by a boy named Nathan in an orphanage. A kindhearted young teacher starts to protect him and finds a nice couple willing to adopt him. Then she wakes up to find herself in her nightgown where Mr. Sinister says she's been meddling in his affairs. The next day she suddenly acts completely different and cold towards Scott. The couple who wanted to adopt him are killed when their small plane crashes into a mountain.
  • Sinister was originally a different type of character, considered too horrific to go to press as proposed. Ever wonder why such an example of Nightmare Fuel went by such a silly name? The original Sinister was the psychic projection of the bully in the above example. It was, essentially, a sentient mass of childhood fears, that itself matured and learned and grew older: your childhood bogeyman who had natural fears in his arsenal.
  • Let's be honest, the entirety of what happened to Scott in Sinister's orphanage is completely terrifying: Let's imagine that you're a nine year old boy, who's just woken up from a year-long coma, the only member of your family who wasn't killed in a plane crash has been adopted and taken away from you to make you psychologically vulnerable, you're bullied by the other orphans and adults, and to top it all off a mad scientist from the 19th Century regularly takes you to a lab for experiments and wipes your mind afterwards, leaving us with no idea exactly what he did to you all those times.
• The Brood show one way that you can possibly make Xenomorphs even worse. The Brood are a parasitic, insectoid race that use other creatures as hosts for their offspring. But, rather than pulling a Chest Burster, the embryonic Brood absorbs the host entirely, stealing all of their memories and physically reshaping them into a new Brood. And unlike their inspirations, the Brood aren't mere animals — they're fully sapient and technologically advanced. They're just sadists who view all other life as "food".
  • Special mention must be made of the Brood's primary means of intergalactic travel: the Acanti. A race of peaceful, highly intelligent, empathic, gentle knowledge-seekers who happen to be Space Whales with innate faster-than-light flight. Like the parasites they are, the Brood infect the Acanti's brains with a virus that allows them to utterly control the Acanti, whilst still leaving the gentle creatures awake and aware inside its now uncontrolled body. They then infest its living body, using it as both a vessel and a food source, slowly devouring it alive from the inside out over countless centuries in between using it to spread their foul species to countless new worlds.
• Titular villains of the Phalanx Covenant event, the Phalanx; a sapient techno-organic matter conversion virus. Imagine a Zombie Apocalypse, but one where the "zombies" are fully sapient shapeshifting Hiveminded cyborgs, like the nightmare lovechild of a Borg and The Thing. They exist only to fulfil two directives: to infect all carbon-based life they encounter, and to establish communion with the Technarchy, the techno-organic alien race which created them in the first place. In addition to the countless horrific flesh/metal constructs they make, and forms they take, the Phalanx also possess the ability to reverse-engineer defenses from every attack they suffer, making them incredibly hard to take down.
  • Perhaps the most horrifying thing about the Phalanx is their true purpose: the Phalanx are food for the Technarchy, who derive sustenance by utterly absorbing the unique bio-energy fields generated by techno-organisms. In effect, the Phalanx are cattle who freely march into the slaughterhouse, because they have been programed down to their equivalent of DNA to want to meet the Technarchy.
  • Imagine being a Phalanx; you have spread your "gift" to an entire world and finally summoned your makers with a Babel Tower — an intergalactic broadcaster constructed from technorganic bodies all merged into a single mass. You are filled with religious rapture as your creators descend and you are brought into the company of your gods... and then you are betrayed as they devour you utterly, sucking you dry of life, consuming everything you were and digesting you without so much as a stray thought, because you never never anything more than food for your gods.
  • How did the Phalanx come to threaten the Earth? Why, human stupidity, of course! See, the first Phalanx encountered on Earth were a bunch of fanatical human supremacists who, in the wake of the recent destruction of the Sentinel project, got their hands on the corpse of Warlock, a member of the Technarchy. They extracted the Transmode Virus from Warlock's corpse, and then decided they could infect volunteers with it to create "Super Sentinels" to destroy mutantkind with. Instead, the Phalanx immediately revert to their genetic imperatives and start trying to assimilate all life instead. It actually forces the last member of the original project team, who was only partially assimilated, to team up with the X-men in order to destroy the Phalanx before they can annihilate humanity.
• Chris Claremont's expansion on Jean Grey's last moments in the space shuttle, to save/explain/make the best of the mandated Retcon about Phoenix. The dying Jean's conversation with the Phoenix entity is truly horrifying.

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