[[folder:General]]
* Skulduggery himself. An animated skeleton who is so crazy and untrustworthy that even his friends don't think Valkyrie should be around him.
** Pretty much any time Skulduggery [[BewareTheNiceOnes loses his cool]]. The best examples would be during Dark Days after being tortured by The Faceless Ones for a year or when [[spoiler: Erskine Ravel murders Ghastly and Anton as part of his plans.]]
* The amount of pervy men who openly lust after the teenage Valkyrie throughout the series. The worst has to be Anathem Mire.
** Not to mention Deacon Maybury ''using Ryan's body to try and kiss her'' in End of the World. [[{{Squick}} He almost succeeds too.]]
** "I haven't killed anyone so pretty in years."
* Some of the more... graphic descriptions. See also YourHeadAsplode.
* The Reflection. Let's face it, it's creepy as hell.
** The Reflection beating the crap out of Moore. And then saying that they should kill him and get Skulduggery to help hide the body.
** The creepiest thing about the Reflection in ''Last Stand of Dead Men'' was that she was so ''human.'' Crying when Valkyrie calls her "Stephanie", crushing on Fletcher, playing with Alice...
[[/folder]]

[[folder:Phase 1]]
!!Skulduggery Pleasant:
* The water-soluble mook of Serpine's in the first book probably qualifies, too.
** The whole scene where he breaks into the Gordon's house could count. Imagine, being a twelve year old girl, all alone in a large house where you uncle recently passed away it, during a storm, and some stranger calls on the phone.
* The description of Mr. Bliss in the first book.
** Oh, Mr. Bliss isn't that bad. His [[spoiler: death]], on the other hand...
* The White Cleaver. It can't be killed. It can't be escaped. IT NEVER STOPS CHASING YOU WHEN IT IS AFTER YOU. This thing is like Franchise/TheTerminator.

!!Skulduggery Pleasant: Playing With Fire
* The Grotesquery. An amalgamation of various creatures, one of which is a fragment of the Faceless Ones. It's purpose is to bring them back to the world, something it succeeds in. One of the things it does is ''tear the scalp off'' of the Torment.

!!Skulduggery Pleasant: The Faceless Ones
* The Faceless Ones themselves, especially when the reader finds out that 'faceless' is not a metaphor. When a Faceless One possesses a vessel, the vessel's face ''melts off’’.
* Anathem Mire. And his house. Definitely his house.

!!Skulduggery Pleasant: Dark Days
* Skulduggery himself, in the beginning of ''Dark Days''. When Valkyrie rescues him, he's so out of it that he mistakes her for a hallucination. There's just something really scary about how Skulduggery, a character who's seemed a bit odd so far but nothing really bad, is completely off his rocker and Valkyrie basically has to drag him back to their own world.
** Special mention goes to when he finds out that he's been followed by Weeper, a not-very-threatening agent of the Sanctuary. Skulduggery appears to be about two seconds away from blowing the poor guy's brains onto the pavement before Valkyrie's intervention, all the while muttering about how he would "usually kill people who follow me... simple and clean." [[BlatantLies Later on, he tells Valkyrie]] that it's part of a BatmanGambit.
* Tanith's torture and imprisonment in Dark Days. She was ''nailed to a chair'' for at least a day by the Remnant possessing Kenspeckle Grouse. Worse still, this remnant then goes on to possess Tanith herself at the end of the next book.

!!Skulduggery Pleasant: Mortal Coil
* The Remnants definitely qualify. Spirits that seem to be made of pure rage and black smoke and shove themselves down your throat in order to possess you. .
* [[VoiceOfTheLegion Finbar being possessed by the Faceless Ones.]]
** Possibly made better (or even worse) by the fact that Finbar doesn't think it's that unusual.
* Kenspeckle's death in ''Mortal Coil''. Clarabelle, the quirky, sweet, but somewhat dim assistant, is possessed by a Remnant and is found sitting on top of him hold a scalpel and covered in blood. Too be clear, most Remnants just leave their hosts recognisable, and entirely rational, if devoid of a conscience. ''Clarabelle'' with a Remnant? She goes ''completely batshit insane''.
* In ''Mortal Coil'', Valkyrie needs to have her true name sealed. The ensuing scene is not for the [[{{Pun}} faint of heart.]]
* The Dullahan dragging off a random woman.
** Special mention goes to dead!Valkyrie, who is almost as creepy as Darquesse. 1) Dead people aren't supposed to be able to use Necromancy (which is a creepy discipline at the best of times). Not only can she use it, it's like the shadows are eager to do what she wants. She just thinks about stopping Nye from getting away and ''the shadows break his leg''. 2) She scares the crap out of ''Nye'' who is horrifying himself. 3) The emotionless way Valkyrie says that she'll kill Nye if he doesn't fix her is kind of disconcerting. 4) This all happens while she has her heart and other organs shoved in a bag. 5) The fact that she's Darquesse suddenly becomes a lot more believable. 6) Hallucination!Skulduggery is both terrifying and depressing. 7) The way the shadows are described gives the impression that they're sentient. ''"The shadows played with Valkyrie's hair."'' *shudder* Sweet dreams, people.
*** How about the surgery itself? The ''sounds'' described...
--->'''Hallucination Melissa:''' My Stephanie would never kill anyone.
--->'''Hallucination Desmond:''' My Stephanie would.
** Remnant Clarabelle should get a special mention. The other Remnants are basically just evil versions of themselves. When Clarabelle gets possessed, she goes ''bat shit insane.''
** Remnant Fletcher also deserves a mention for being so damned ''creepy'' (what with his IHaveYouNowMyPretty moments with Valkyrie). Especially in contrast with [[ButtMonkey his]] [[NiceGuy normal]] [[NonActionGuy self]].
* Darquesse killing all those people.
* [[MadDoctor Doctor]] [[HumanoidAbomination Nye]] in general. The fact that s/he's barely described [[NothingIsScarier makes it even worse.]]
** Nye now works for the Sanctuary. Every time Sanctuary agents get hurt, they are patched up by a magic version of Josef Mengele.
** The large amount of {{Squick}} and FridgeHorror involved with Remnant!Tanith definitely applies. She is being possessed by the same Remnant that nailed her to a chair. The Remnant (in her body) is in a romantic relationship with someone who wants to kill her friends and at one point fantasized about slitting her throat. She can't stop herself from doing ''anything.'' The conversation it has with Valkyrie (while her ''parents'' were there) was one of the more creepier parts of a very creepy book. Also? It's suggested to be permanent.
* Lord Vile telling Skulduggery that he's going to kill Valkyrie at the end of ''Mortal Coil.''

!!Skulduggery Pleasant: Death Bringer
* The [[HumanoidAbomination Jitter Girls.]] [[FluffyTheTerrible The name isn't very threatening]] compared to the likes of Nefarian Serpine and Lord Vile. They literally ''jitter''... as in Japanese Horror movie jittering... and have a horrific back story. When Skulduggery sees them, he backs against the wall and tells everyone to hide.[[BreakTheBadass Really.]]
** The way the attack Valkyrie by literally putting a hand through her skull and rummaging around in her brain and her subsequent retaliation in which Darquesse, who has been awakened by the aforementioned brain-grabbing, [[CurbStompBattle curb stomps]] them and then threatens Skulduggery out of pure curiosity isn't much better either.
* Lord Vile, if only Skulduggery's reaction to seeing him at the end of ''Mortal Coil.''
** Ghastly talks to Tanith about his mother. The woman was badass incarnate. She beat both Baron Vengeous and Serpine into retreat. Some of Mevolent's best men would see her and ''run.'' Her mistake was going against Lord Vile.
* Ian Moore. Unlike any other antagonist, Moore is just an ordinary mortal man. After being beaten to near death in his cell by a vengeful Valkyrie, he's allowed to leave and decides to take vengeance on the girl. [[SurprisinglyRealisticOutcome He very nearly succeeds, due to being an adult man against a teenage girl.]]
* Caelan, anyone? He kisses (in a disturbingly passionate way) and stalks a sixteen year old. Comparisons to Literature/TheTwilightSaga are fantastic NightmareRetardant, however.
* ''Everything'' about Lord Vile's battle with Darquesse. [[OhCrap They're both evenly matched. Darquesse can heal. Lord Vile's armour makes him practically invincible.]] They're both incredibly powerful [[OmnicidalManiac Omnicidal Maniacs]] so it's looking pretty dim for humanity. Also? Easily the bloodiest, most disturbing battle in the entire series (which is saying a lot) is technically between Valkyrie and Skulduggery.
** Darquesse lets Vile ''gouge out her eye'' for an ''experiment''. ''Deliberately making sure she feels the full pain of the experience''. And when she determines she knows what its like to have her eye gouged out, she ''shuts the pain off'' and grows it right back. [[RefugeInAudacity While flying.]]
* Valkyrie, after being tortured by Melancholia] [[DissonantSerenity She doesn't panic. She's confused about her hands not shaking.]] And then ''Darquesse'' starts whispering to her. Getting her to calm down.
** ''Soon.''

!!Skulduggery Pleasant: Kingdom of the Wicked
** In ''Kingdom of the Wicked'', he has to put up with both China and Serpine. [[TranquilFury He's very calm]] and you constantly get the impression that he's just two seconds from killing someone.
* Kitana ordering her gang to kick Valkyrie to death.
* Lord Vile from the AlternateUniverse is even worse. It's implied that Skulduggery didn't snap out of it and as a result, Mevolent won the war. Alt!Vile hasn't had five years to grow powerful... he's had ''centuries''. He cuts Alternate!Ghastly in half. Note Ghastly was wearing his own armored clothing, which can block bullets.
* The end of ''Kingdom of the Wicked''. Just... yeah.
* Darquesse getting her head ripped off in ''Kingdom of the Wicked.'' And then putting it back on.
** Even worse was her jaw and hand getting burnt off. Especially seeing as how she didn't seem especially concerned about either injury. She cared enough to heal them, sure, but she didn't even seem to really ''feel'' hurt.
* Alternate Universe Mevolent. His relatively mild and amiable attitude makes it all the worse.
-->'''Mevolent:''' Words, Valkyrie. Use your words.
* Carol's conversation with Valkyrie in ''Kingdom of the Wicked'' makes it clear that her sister is an undiagnosed anorexic. The depiction of what it feels like to have such a mentally-ill loved one is so spot-on it's like a punch to the gut. It gets worse when you realise how quickly Crystal must be deteriorating for her to have gone from normal in the last book to ''[[DemBones comparable to Skulduggery]]'' in this one.

!!Skulduggery Pleasant: Last Stand of Dead Men
* ''Last Stand of Dead Men'' has Skulduggery, Dexter Vex, Saracen Rue, Gracious O'Callahan and Sanguine forced to watch Ghastly and Anton get murdered on the other end of a video link. Gracious, Vex and Saracen all hit varying levels of HeroicBSOD. [[JerkAss Sanguine]] finds the whole thing funny. Skulduggery just ''strolls to the mirror and casually checks his tie and hat''. When finally asked what he intends to do, he responds [[TranquilFury calmly]] and [[HeroicSafeMode conversationally]].
--> '''Skulduggery:''' Oh, that. [[UnstoppableRage We kill them]]. [[RoaringRampageOfRevenge We kill them all]].
* China almost burning herself alive. Described. Also. China almost getting killed by a swarm of spiders. That get in her mouth. NOPE.
* An ''entire chapter'' of Darquesse [[MindRape mind raping]] Valkyrie into giving in. While she's getting ripped apart by witches.
-->''kill him kill him kill him kill him kill him kill him kill him''
** The entire chapter is dialogue-only. We pretty much watch as Darquesse mentally tortures Valkyrie into losing her identity. It's the most sinister case of EnemyWithin so far, bordering on psychological horror.
--> Every thing I’ve done and every life I’ve taken, you were there. You remember it all. You tell yourself that I’m the wicked one and you don’t have any choice in the matter. That’s how you sleep at night. But it gets to you. Of course it does. You have so much blood on your hands.

--> Walking quickly won’t change that. Wherever you go, you take me with you, remember?
* Skulduggery performing a MercyKill on his soldiers who were going to be burnt alive.
* [[TranquilFury Skulduggery]] and [[spoiler:Ravel's]] conversation.
-->'''Ravel:''' *on his knees, gun at his head* What's it going to be? Assassination, arrest or kidnapping?
-->'''Skulduggery:''' Keep talking. I haven't made up my mind.
-->'''Ravel:''' Well, if these are my final few moments, I'd like you all to know how sorry I am about Ghastly and Anton.
-->'''Skulduggery:''' *taking a step back to avoid ''bloodsplatter''* Assassination it is.
* The context of the scene is a really bizarre mixture of this, Heartwarming, FandomNod and Tear Jerker, depending on your whole view of the Valduggery/Vilequesse situation, but Darquesse ''kissing'' Skulduggery (yes, right on the mouth) and calling him "her favourite little toy." Right before killing him.
** ''Alice'' being included in the vision. '''NO.'''
* Skulduggery getting pissed off enough with Stephanie to point his gun at her. Fletcher has to stand between them.
* The Sensitive who starts messing with Valkyrie's head in order to find out where the Dead Men are hiding. We see Remnant!Clarabelle chopping Kenspeckle to pieces while he's calmly talking to Valkyrie, Skulduggery wearing a facade of black shadows and then Darquesse starts messing with the Sensitive.
* Basically, just Darquesse in the last part of ''Last Stand of Dead Men.'' After mockingly telling everyone that they're just [[AGodAmI insects to be crushed,]] she them gives Ravel a ToThePain speech and goes through with it. He may have crossed the MoralEventHorizon, but ''no-one'' deserves to spend twenty-three hours each day, every day, until death, in screaming agony.
** Admit it, you got chills when Darquesse appeared in the sky over Roarhaven. [[NothingIsScarier She doesn't even say or do anything, she just floats there, above the battle. It's not until she swoops down and starts murdering the ''hell'' out of anything that come close that [[OhCrap the gathered sorcerers realise what kind of mess they are in.]]
*** Worse still is the FridgeHorror realization that the only reason why the world's not a dead wasteland is because Darquesse doesn't want it to be. ''Yet.''
---> She wondered how hard it would be to turn the whole city to dust. Probably not that hard. Not if she concentrated.

!!Skulduggery Pleasant: Dying of the Light
* Alternate Lord Vile's improvised facade in ''Dying of the Light.'' [[FaceStealer He just cut off some dude's face and wore it.]] As you do.
* And the award for the most messed-up scene in the series goes to... Valkyrie ''killing'' her baby sister. Granted, she's revived almost immediately. But the fact remains that Valkyrie killed Alice just to gain the power of the Sceptre. This, on top of everything else that happens in ''The Dying of the Light'', is enough to traumatise Valkyrie to the extent that she leaves her family and Skulduggery to live in America for five years.
* Stephanie's death is ''brutal'' and help is just out of reach. There's no magic. Darquesse simply possesses a much larger man and ''beats the crap out of her.'' Her extensive training isn't enough to help her because Darquesse has had the same training. Which is terrifying for any woman who has taken a self defense class. To make matters worse, the chapter is written in her point of view and you see just how desperate she is to live before her thoughts just trail off. According to his twitter, Derek traumatised ''himself'' writing this one. Considering the man is responsible for this entire goddamn page, that's impressive.
[[/folder]]

[[folder:Phase 2]]
!!Skulduggery Pleasant: Resurrection
* The voices in Valkyrie's head don't go away after Darquesse leaves Valkyrie's body.
** In fact, ''Resurrection'' implies that the voice is a remnant of Darquesse left in Valkyrie's mind after the two are separated, living on long after Darquesse's death.
* In ''Resurrection'', we have Smoke's powers of corruption, which make anyone he touches turn BrainwashedAndCrazy, up to and including ''Skulduggery''. As a result, Skulduggery spends roughly half of the book wanting to violently murder Valkyrie. And unlike Lord Vile, who hardly ever spoke, this evil version of Skulduggery is just as polite and talkative as the real thing.
* The BigBad of ''Resurrection'', Abyssinia. This person is someone so dangerous and terrifying that the Dead Men and the Diablerie - two elite teams on opposite sides of the war with Mevolent - went so far as to [[EnemyMine team up in order to take her down]]. Oh, and her manipulations are largely responsible Skulduggery having become Lord Vile in the first place.
* All of Savant Vega's ordeal throughout ''Resurrection''. Locked inside a necronaut suit for ''five years'', forced to watch his beloved husband abandon all principles and work with a team of gleefully violent psychopaths who intend to murder god knows how many mortals and sorcerers to achieve their goals, all just to get him back alive, and has his body and powers hijacked in order to do lead said aforementioned group of monsters. No wonder there's no confirmation of a definite HeelFaceTurn by the end of the book - the poor man's mind may well be irreparable.

!!Skulduggery Pleasant: Midnight
* Valkyrie's sister Alice being taken hostage by Cadaverous Gant, a man whose power is that he's invincible on his home turf. This time, he's made the Midnight Hotel his home, transforming it into his own MentalWorld.
* The entire scene at the end of Midnight with Crepuscular was unnerving to say the least.
** Special mention goes to Mr. Hogan the florist, [[DoesThisRemindYouOfAnything who has very paedophilic undertones.]] And Alice goes into his shop.

!!Skulduggery Pleasant: Bedlam
* The scene in Bedlam where Valkyrie is buried alive and drugged. [[PaintingTheMedium The text reacts]] [[UnconventionalFormatting accordingly: ]]
** -->Her mind went

--> a

--> w

--> a

--> y

In the dark.
* Valkyrie becoming dependent on the music box to get her through stressful situations. The same music box used to keep Solace tranquil while she was locked up for years in Greymire Asylum.
* Valkyrie being beaten half to death in her cell.

!!Skulduggery Pleasant: Seasons of War
* Liebniz!Lord Vile returns once and is at his [[{{Pun}} most vile]] here. When the heroes return to the dimension to assassinate Leibniz!Mevolent, the place has been overrun by Draugr who are his creations. These foul creatures have turned anything they come into contact with into more of themselves, with even the Necromancers being undead. Worse still, Liebniz!Lord Vile goes as far as to kill his boss, all because he wants to kill everything.
** During the fight with Liebniz!Lord Vile, Skulduggery transforms into Lord Vile and [[MirrorMatch the two fight.]] Unfortunately, Liebniz!Lord Vile is superior thanks to having been Vile for far, far longer, draining Skulduggery of his darkness and reverting him back to normal.
*** Further still, the Draugr infection is so bad that it drives Liebniz!Mevolent to stage an invasion of the main dimension, causing an influx of dimensional immigrants in the process.

!!Skulduggery Pleasant: Dead or Alive
* Damocles Creed's plan to find the Child of the Faceless One involves mass murder, akin to the scene in [[Anime/NeonGenesisEvangelion End of Evangelion]] where everyone is turned to LCL. Worse still, he succeeds in corrupting Alice into his enforcer and creating a dictatorship 72 years into the future.
* The future 72 years later is creepy. The Faceless Ones have returned and the whole thing is peaceful, except for the fact that mortals are slaves to sorcerers, Valkyrie Cain was turned into a vicious harpy that attacks anyone she sees, Skulduggery went dark again, having regained all of his Vile memories, and [[MeaningfulRename renamed himself to Cadaver Cain]] soley to torment Malice while destroying the Faceless Ones as part of his scheme to wipe out all life in the universe

!!Skulduggery Pleasant: Until the End
* After the Shalgoth emerge from the earth, things go to shit ''very'' fast. The future that Skulduggery feared that Argeddion's plans would create comes to pass, with Armageddon spreading across the Earth. With Doctor and Professor Nyes's help, Martin Flannery is able to create super-soldiers who use magic, but are also mentally unstable, killing each other as much as they do the enemy. In addition, the mortals prove that they're a threat to the sorcerers, with several mentions of sorcerers being burnt at the stake or being hung from lamp-posts with their foreheads labeled "WITCH".
* The last moments of humanity must've been terrifying. Imagine that suddenly, your civilization comes to end. Technology stops working. Electrical objects no longer work. Planes fall from the sky. Hospital equipment no longer works. It was already bad enough for mortals when the Faceless Ones were roaming freely, and the Shalgoth were rampaging across the planet and that is before Obsidian comes in to finish the job by erasing the Earth from existence along with the rest of the universe. Thank goodness that Darquesse was willing to recreate the universe.
[[/folder]]

[[folder:Phase 3]]

!! A Mind Full of Murder

* The book digs in deeper into the trauma of magical people remembering the end of the world, which in one case includes a character being ''burned alive by her friends after trying to protect them''. When one of her mortal friends finds out that in another timeline he did that, he is utterly horrified, repeatedly refusing absolution because it wasn't technically him (pointing out that under those circumstances, it ''was'' him).
** It also reveals that a lot of people with limited or latent magical gifts that hadn't previously done much with them or known they were there, were suddenly saddled with these horrific memories and spent years trying to cope without any kind of support.

[[/folder]]

[[folder:Spin-Offs]]
!!Skulduggery Pleasant: Armageddon Outta Here
!!Skulduggery Pleasant: The Maleficent Seven
!!Skulduggery Pleasant: Apocalypse Kings
!!Skulduggery Pleasant: Grimoire

!!Skulduggery Pleasant: Hell Breaks Loose

* While we've seen Lord Vile before, and seen an evil Skulduggery, we've never seen a Skulduggery on the verge of snapping or why his quiet rage is so feared. He spends ''the entire book'' in this state, [[SoftSpokeSadist never once raising his voice]], or [[OOCIsSeriousBusiness cracking even one joke]] and having to be more or less constantly accompanied because he might murder someone otherwise. And then, he turns into Lord Vile, at least half a century early, immediately re-establishing Vile's reputation for horror.
[[/folder]]
----