[[quoteright:328:[[Franchise/{{Alien}} http://static.tvtropes.org/pmwiki/pub/images/RuleOfScary_9298.JPG]]]]
[[caption-width-right:328:[[Series/PimpMyRide Yo dawg, I heard you like mouths.]] [[MemeticMutation So I put a mouth in your mouth, so you can scream while you scream]].]]

Like the RuleOfCool and the RuleOfFunny, the Rule Of Scary says that if it's creepy enough, it doesn't matter how illogical it is. Why the maniac has a hockey mask, where he got it, and how it survived a shotgun blast to the face are irrelevant. All that matters is that it [[NightmareFuel creeps you out]].

'''Most effective formulas for scary:'''

* Mixing the paranormal or abnormal with the mundane and familiar. Even if the WillingSuspensionOfDisbelief remains intact, [[FantasticallyIndifferent blatantly scary things are easy to shrug off]] when they are happening in a completely [[SpaceWhaleAesop unrelatable situation]]. But when the same elements are placed side-by-side with familiar settings and elements, suddenly TheFourthWallWillNotProtectYou. Even with flawless special effects a StarfishAlien in an EldritchLocation can be mere {{Narm}}, but invoking the UncannyValley with a HumanoidAbomination in an AbandonedHospital can be downright terrifying.
* [[LastNoteNightmare Ending on a note]] [[BreadEggsMilkSquick or element]] no sane person would. You'll find [[HumansAreTheRealMonsters humans are psychopathic]]. What is funny, notched up, is scary (and still kinda funny.) Exempli gratia: [[Film/TheDarkKnight "How about a magic trick? I'm gonna make this pencil disappear..."]]
* Vividly showing (or describing) something scary which directly affects the human body. BodyHorror is a part of this, but this is not always BodyHorror. eg, ''Film/TheMatrix'' using humans as "living batteries", or some portrayals of viruses. ArtMajorBiology is a major factor in this.
* [[NothingIsScarier Not showing anything]], and [[TheUnreveal leaving some things unexplained]]. This works on the (fairly reliable) premise that no expensive special effect or clever writing can ever top what the viewer imagines to fill in the blanks. Used well, this method creates suspense, [[MonsterDelay enhances the ultimate reveal]], and can magnify a simple JumpScare into a [[BringMyBrownPants Brown Pants Scenario]]. Often combined with HellIsThatNoise and ObscuredSpecialEffects. OffscreenTeleportation, {{Unreveal Angle}}s, and implausibly agile monsters using [[AirVentPassageway Air-Vent Passageway]]s are all classic methods of keeping the scary unseen as long as possible. The plot aspect often involves HisNameIs, {{Conveniently Interrupted Document}}s, {{Apocalyptic Log}}s, and/or PlotBasedPhotographObfuscation.
* [[DaylightHorror Just making something mindblowingly scary and showing it in all its well-lit horrific glory]]- the hardest to pull off, as it [[TemptingFate risks]] highlighting even minor {{Special Effects Failure}}s and ConspicuousCGI unless done superbly, and often has to overcome the lack of menacing atmosphere. On the rare occasions it is done well, however, it can be absolute NightmareFuel, all the more jarring because both [[GenreSavvy viewers and characters]] tend to associate well lit areas with safety- [[WrongGenreSavvy which is not always the case.]] Numerous particularly well-done instances of this form can be seen in Series/TheWalkingDead, with walkers as likely to attack in open fields in broad daylight as in dark basements, making for prime ParanoiaFuel.

If you cannot tell from the listings below, this is overwhelmingly a {{Film}} trope. Whether this is because producers [[TheyJustDidntCare don't care about silly things like logic]], or they just don't have enough time to explain every little idiosyncrasy is a debate that will rage on for as long as the medium exists.

See also HandWave, NightmareFuel.

Compare FridgeLogic. OffscreenTeleportation is a SubTrope of this, as is BodyHorror.

Contrast {{Narm}}, NightmareRetardant, RuleOfCute.
----
!!Examples:
[[foldercontrol]]

[[folder:Film]]

* Many of the dinosaurs in ''Franchise/JurassicPark'' were deliberately stylized to be more menacing. The velociraptors are a particularly evident example.
** It doesn't stop there: why in blazes would a door lock ever be tied to an electrical grid in such a way that it cannot be manually operated? There's no sane reason for that whatsoever apart from this trope. It also explains why Tim and Lex keep a tight grasp on the IdiotBall several times: if they didn't do incredibly stupid things, the dinosaurs wouldn't be able to menace them constantly and create tension.
* ''TalesFromTheCrypt''. In the [[Film/ECComics 1972 movie]], when the TwistEnding begs the question of how [[spoiler:both a man who is supposed to "live forever" and a man stuck an an infinite dream sequence loop have died and been sent to Hell]].
* ''Film/TalesFromTheDarksideTheMovie'' could make one wonder how [[spoiler:an above average size domestic cat can able to fit [[OrificeInvasion a person's mouth, even before crawling all the way down the throat]]]].
%%* Most anything on ''Chiller''.
* The xenomorph's life cycle from'' Franchise/{{Alien}}'', based on the way a spider wasp lays its eggs, as facehuggers implant embryos into their victim's chest. The xenomorph's have LEGOGenetics, as exampled in ''Film/{{Alien 3}}''. So the embryo's host also provides the fertilization.
** Similarly, the Xenomorph's quick growth to adulthood, despite lacking any apparent source of food, or the laws of physics. The only important point is that the tiny creature they were hunting for has suddenly gotten much bigger, more dangerous, and is now hunting them.
* A great many films that [[FollowTheLeader ape]] ''Film/TheRing'' are like this - precisely why or how a ghost got into your video cassette/mobile phone/microwave oven, or why this should cause demented ghost like creatures to stalk you until you die is never explained and, when you think about it, is probably a pretty daft idea, but nevertheless, the films can still be exceedingly creepy.
** [[{{Ringu}} The Japanese version]] does eventually explain how everything actually works, including the tape, but the actual explanation is actually strange enough to make it [[NightmareRetardant less scary]] in hindsight.
** If you read [[Literature/TheRing the novel]], it explains most things scientifically. Made it more a science fiction than a ghost story though.[[spoiler: In the novel, Sadako is not a ghost.]]
* Why can't the blind crawlers smell the tasty humans hiding a foot away in ''Film/TheDescent''? Because they're too busy being terrifying, that's why.
* In the ''Film/{{Feast}}'' films, we never find out exactly what the monsters are. All we know is, they like eating things and raping things.
* ''In Film/{{Psycho}}'', Mrs. Bates' rocking chair acts like a swivel chair around the end of the movie, entirely for the benefit of a ''very'' creepy shot. Audiences were okay with this.
* The films of Creator/DarioArgento (''Film/{{Suspiria}}'', ''Film/{{Tenebre}}'' and especially ''Film/{{Phenomena}}''), in particular, operate on a sort of bizarre dream logic. Things that make next to no sense are often seen to occur, but since the entire point of such events is to make the audience extremely nervous, the lapse in rationality is forgivable.
*** The best of the Italian horror film makers, including Creator/LucioFulci, the Bavas, and Michele Soavi, are very good at this. The lesser ones attempt this, and the results are usually still at least entertaining.
* ''Film/SoylentGreen'' utterly obliterates the laws of Thermodynamics, but that doesn't stop it from being extremely disheartening. In fairness, the film never suggests that it's meant to be sustainable, and you could probably argue that it's a deliberate way of reducing the surplus population.
** This is also true of the "human battery" thing in ''Film/TheMatrix''. Although it ''is'' a case of ExecutiveMeddling; it was originally supposed to be human brains linking up to make a giant supercomputer. Not that a supercomputer using human brains in a network makes a whole lot of sense either.
* ''Film/{{Eraserhead}}'' is completely [[TrueArtIsIncomprehensible incomprehensible, like all True Art]], and profoundly disturbing.
** Almost anything by Creator/DavidLynch, really. His short film ''Rabbits'', for example. His creative process is that he will come up with a visual idea or a scene that interests him (not always scary, but often) and then make a film around it, without trying to justify or explain some of the weirder elements. In some cases (such as the Man Behind Winkies scene in ''Film/MulhollandDrive'') it will barely even be worked into the main narrative.
* Any objections people had to the reinterpretation of Dr. Jonathan Crane in ''Film/BatmanBegins'' from a university professor to an asylum manager were forgotten the moment we saw his [[MaskPower mask]] and his use of a chemical that can literally be called "NightmareFuel".
** The very fact that SelfDemonstrating/TheJoker has any capacity to do anything that he does, ''ever'', breaks most common sense, but damn isn't he funny and scary for doing it. The song [[http://www.youtube.com/watch?v=vbgLapRAloQ&feature=fvw The Dark Knight Is Confused]] sums them up perfectly: The Joker's goons are schizos who are nevertheless dependable and self-sacrificing and for a guy who doesn't look like he had a plan, he musta organized these attacks on an evil day planner.
* This trope is why, in ''Film/ANightmareOnElmStreet1984'' and [[Franchise/ANightmareOnElmStreet its sequels]], villain Freddy Krueger wears a red and green Christmas sweater. Creator/WesCraven had read that those colors together tend to mess with viewers' eyesight, and produce a generally unsettling result.
** Also, Freddy's glove. It isn't nearly as efficient as an axe, a machete, or hell, a ''gun'' would be as a way to murder people. But it hits the middle ground between RuleOfCool and Rule Of Scary quite nicely. Also, Freddy's glove was intended to be as much a torture device as a killing tool. In ''Film/FreddysDeadTheFinalNightmare'' you can see a variety of gloves in his basement, including one with what look like rusty nails for knuckles and one with straight razors attached to the tips. Also, he specifically killed young children. What would terrify a child more than ''that''? And since Freddy exists in nightmares, nothing he does has to be practical and can be as terrifying as possible. Freddy is basically Rule of Scary incarnate.
** To a lesser extent, this is true of most slasher movie villains. ''Frachise/{{Halloween}}'''s Michael Myers uses a kitchen knife, while most of the murders in the ''Franchise/FridayThe13th'' films are done with a machete and ''Franchise/TheTexasChainsawMassacre'' was committed with [[ChainsawGood chainsaws]] (and sledgehammers, a surprising amount of the time), and there are other films with names like ''Film/TheNailgunMassacre'' and ''Film/TheDrillerKiller''. Slashers use everyday, utilitarian objects as weapons because it's scarier than using a gun, even though a gun would be easier. This trope also covers their common powers of OffscreenTeleportation.
*** ''Halloween'' actually tried to justify this in one of the later sequels by revealing that its killer actually had magical powers the whole time, explaining some of his more improbable feats. Audiences weren't happy, feeling that it was better when it was operating wholly off of this trope, with no justification.
* Technically, a faun really oughtn't to be made out of rotting wood, but ''Film/PansLabyrinth'' was so disturbing that this can be forgiven. Also, the Pale Man walks really slowly and isn't all that dangerous, although this is partly justified by the implication that he's been starving for some time, without [[ChildEater any kids to eat]]. Still...
* ''Film/TheNightOfTheHunter'' applies this to the villain's OffscreenTeleportation. Asks one character, "[[LampshadeHanging Don't he never sleep?]]"
* ''Film/TheCabinetOfDrCaligari'''s town of Holstenwall looks very [[{{Bizarrchitecture}} structurally unsound]]. Of course, there's [[spoiler: [[AllJustADream a good reason for that.]]]]
* Let's let Stomptokyo.com explain how this trope failed to cover the glaring improbabilities in the BerthaInTheAttic-style plot of ''[[http://www.stomptokyo.com/movies/b/bad-ronald.html Bad Ronald]]'', shall we?
-->''The thought that an orphaned lunatic might still lurk in the forgotten corners of a creaky old house is enough to make you start knocking surreptitiously on the walls of your own home, listening for hollow spots. However, this central conceit probably worked better as a novel than as a movie. On film, it becomes obvious that Ronald's subterfuge wouldn't last long once the other family moved in. Besides the fact that the lack of a shower in his room would probably mean that Ronald's body funk would knock passing planes out of the sky, Ronald couldn't possibly be quiet enough that everyone wouldn't figure out something was up. "It's just the house settling" only goes so far, especially when you consider that Ronald has a toilet in there. ("My house is haunted by a Phantom Flusher!") When Ronald carves all of his peepholes at eye level, the idea that he could go unnoticed in the house becomes downright ludicrous.''
* Another failed example: the theatrical ending to the movie ''Joy Ride'', as detailed under the entry for ShockingSwerve.
* ''Film/EventHorizon''. The jokes about it being a prequel to ''TabletopGame/{{Warhammer 40000}}'' are ''not'' helped by the fact that, for no apparent reason, the FTL drive and the room containing it look like a shrine to Chaos, complete with SpikesOfDoom on ''everything''.
* Oddly enough, ''Franchise/{{Godzilla}}'' could be said to fall under this trope, in some of his darker incarnations. In reality, a dinosaur his size could be killed with a single airstrike, or, more likely, by [[SquareCubeLaw his own weight]], but when you start to realize that he's actually an unstoppable natural disaster that just happens to be ''shaped like'' a dinosaur, you realize how screwed the world is. Some of the films almost feel like [[CosmicHorrorStory Cosmic Horror Stories]].
* ''Film/{{Phantasm}}''. None of it makes much sense: something about a conspiracy to steal our dead so as to revive them as slaves on another planet. But then there's the Tall Man, those Jawa-like slaves, and that flying ball... there's something surreal about the whole thing, and it just somehow works.
* The ghost/demon from ''ParanormalActivity''. It causes a lot of jump scares by stomping around, dropping pans and slamming doors, but why? None of that helps its objective of [[spoiler:kidnapping children]]. Maybe it just likes to play pranks?
** The parapsychologist/exorcist guy from the first film explains that demons feed on fear and that interacting with it only makes it stronger. By freaking everyone out and provoking them, it's making itself stronger.
* Watching ''Film/TetsuoTheIronMan'' can bring up many questions, such as "How is the protagonist able to live with all that metal growing out of his body?" or "How are the rocket jets in his ankles fueled?" or even "How is this even possible?" The answer to all these is [[NightmareFuel because Shinya Tsukamoto hates you and does not believe in this peculiar idea you call "sleep".]]
* The DisneyAcidSequence of a song "B Movie Show" in ''WesternAnimation/TheBraveLittleToaster''. Why would the doomed appliances at the parts shop go to all that trouble to freak out the protagonists, who are already terrified at the prospect of being stripped for parts? Because of this trope, and also to meet the quota and expected variety of musical numbers.
* ''Film/TheCabinInTheWoods'' is in part a critique of this trope, [[ZigZaggingTrope zig-zagging]] with this and RuleOfFunny (albeit with BlackComedy).
[[/folder]]

[[folder:Literature]]

* H. P. Lovecraft's monstrosities are designed for this. Some of his stories fall flat a little bit today, because [[ValuesDissonance foreigners are no longer considered automatically scary]], but a lot of his stuff holds up very well, tapping into all manner of primal fears without at any point fully telling you what's going on.
* ''Anything'' by Creator/CliveBarker. ''Ever.''
* Similarly, anything by Creator/BentleyLittle. Somewhere between the cult of women who [[CargoShip have sex with a tire iron]] and the humanoid figures in trenchcoats who are faceless except for their huge disembodied grins, you'll realize that absolutely none of the horrifying, insane things that happen in his novels make the least bit of sense; your best bet is to simply assume that the evil...''[[CosmicHorror what]][[EldritchAbomination ever]]''...that's causing it is powerful enough to [[RealityWarper warp reality and do whatever the hell it wants]]. Even making that assumption, most of it still comes across as lunacy. ''Extremely creepy'' lunacy.
* Creator/StephenKing loves this trope. Why the hell is a dog/clown/car/laundry press/platoon of green army men toys/pair of chattering teeth trying to kill people? Why is that kid's dad [[spoiler:turning into a giant, carnivorous man-shaped glob of mold from drinking contaminated beer]]? Where did that man-eating oil slick come from? The answer: Who cares? It just happened, and it's ''scary''.
** And explaining where some of these horrors came from would probably have made them less frightening. Unfortunately, a few of King's stories have done exactly that, and yes, they were less frightening as a result.
** One of the themes of ''Literature/FromABuick8" actually is that some things will never be understood.
** In discussing his early novel ''Firestarter'', Stephen King once wrote that he was unhappy with his clumsy attempts to explain where the protagonist's pyrokinetic powers came from, and ultimately decided that the 'how and why' of his scary ideas didn't interest him as much as the scary ideas themselves.
** Most monsters from Stephen King books can just be HandWaved as having come from a different dimension. This is usually the most in-depth explanation they ever get anyway.
* ''Literature/HouseOfLeaves''. Why does ''any of it'' happen?
** ''[[MindScrew Does]]'' any of it happen?
* ''Literature/HarryPotterAndTheChamberOfSecrets''. How does a giant snake living underneath a castle stay alive for over 1000 years without eating any of the students? Most likely, AWizardDidIt, but that's actually a perfectly satisfactory answer here.
** Some of Voldemort's achievements in a few of the later books go against [[MagicAIsMagicA established laws of what magic can and can't do in the setting]]. Rather than making the audience call bullshit, though, this just makes Voldemort more menacing, because he's doing things that he ''shouldn't be able to do''.

[[/folder]]

[[folder: Live Action TV ]]

* This is second only to RuleOfCool in ''Series/DoctorWho''.
** Overlaps with RuleOfCool in "The Dalek Invasion of Earth". The Daleks' motivation makes no sense at all (they want to hollow out the Earth and turn it into a spaceship), but Daleks destroying most of the Earth and being the masters of a post-apocalyptic, deserted London?
** "The Tenth Planet". Is there any plausibility whatsoever about the Earth having an identical twin planet that's just the Earth upside down? That attempts to drain 'energy' from the Earth until it breaks itself apart and kills everyone on it under some assumption that this is a good plan? Of course not, but the result of it is that the main characters are now trapped in a radio base in Antarctica along with unspeakably creepy BodyHorror {{Cyborg}}s with no emotion who can't even be fought back against and the only hope is to survive until they all die. Very, very suspenseful.
** The Autons. How can a big lump of angry goo turn shop window mannequins into marching, gun-handed footsoldiers and [[AttackOfTheKillerWhatever make troll dolls attack you, inflatable chairs eat you and plastic daffodils spit acid]]? Because shop window mannequins are already UncannyValley and the idea of them moving is a fundamental childhood phobia, and because in the 1970s cheap plastic fad items were enjoying a boom and [[ThingsThatGoBumpInTheNight whenever any child turned off their bedroom lights they would be inside the room to loom over the bed]].
** Many aspects and subplots of the Seventh Doctor episode "Ghost Light" are never fully explained, but the effect is so creepy you don't care... all you actually want is a sofa to hide behind.
** Weeping Angels are built entirely on this trope. They're statues. What's the scariest thing a statue can do? Move when you're not looking. They make people disappear instead of leaving bodies. You have to keep looking at them; you can't just film them because then the film will become an angel. But look at them in the eye and one will start growing '''in your brain'''. Are they scientifically plausible in any way? No! Are they terrifying? OH YES!
** The alien presence in the episode "Midnight" is never explained, because not even the Doctor had any idea what it was or what it really wanted. As such, it's often remembered as one of the scariest episodes the show ever ran.
*** The episode "The Angels Take Manhattan" pushed this one a bit far, though, by revealing that the Statue of Liberty was, somehow, a giant Weeping Angel, and never explaining how that got to be the case. Normally, there's a Sherlock Holmes-style [[TheSummation summation]] at the end of an episode. This time, nothing.
** Why do the dolls in "Night Terrors" turn people into dolls when they grab them? Because it's creepy as hell, that's why.
* [[Series/{{Heroes}} Sylar]], early on, literally has no definition other than this rule, though this becomes less and less true as the series went on [[CanonDisContinuity before vanishing, never to return, by season 2]]. Why does he need to remove the brain? How did he just appear right behind you? How'd he survive/come back to life? What, exactly, are his powers?
* The Borg throughout ''Series/StarTrekTheNextGeneration'' were originally made to be pale/albino guys wearing piecemeal armored suits, cybernetic implants and helmets. Pretty scary, sure. In ''Film/StarTrekFirstContact'' they were {{retool}}ed to fit a modified premise that the Borg assimilate people along with technology, so that their growing Borg drones had the appearance of decayed corpses along with spider-veins. No explanation was given for the change, it just looked much better in a movie format. Looking on the earlier episodes they don't have quite the same sense of dread.
** The process of assimilation into the Borg Collective also "benefited" from this treatment, especially in ''[[Film/StarTrekFirstContact First Contact]]''; Instead of simply grabbing you and teleporting you away to be converted into a Borg at their leisure, they forcibly inject nanites into you and leave you to slowly turn into early-stage Borg from the inside out, adding elements of TheVirus and ZombieInfectee. "Don't let them touch you" indeed.
* ''Series/BuffyTheVampireSlayer''. In "Hush," nobody really cares that The Gentlemen look like gray glittered morticians who can float above the ground and are only single episode villains. The viewers are too focused on their unsettling smiles. It's telling enough that [[WordOfGod Joss]] said he was basically creating creatures that [[NightmareFuel kids would have nightmares over]].
* The third season of ''Series/{{Whitechapel}}'' runs on this trope. '''Everything''' is scary. Case in point: one of the witnesses to a crime (who only has about three seconds of screen-time) is a creepy old voodoo lady. She could have just as easily been portrayed as a normal housewife with curlers in her hair - but no, she's a creepy old voodoo lady. Even places like confectionary stores and the police station are ominous, shadowy places. As a result, even when the show is not being overtly scary, it's still consistently unsettling.
* The supernatural elements on ''TwinPeaks'' all operated on a kind of nightmarish dream logic. There's no explanation for why The Black Lodge looks like a waiting room, or for why all the spirits seem to feed on a kind of demonic creamed corn, or for why one of the main villains is a demon named BOB who looks like an extra in a bar scene and can turn into an owl or something. Additionally, the camerawork and sound design often make seemingly-normal objects - the ceiling fan over the Palmer family's staircase, or the traffic light outside the Double R Diner - seem like the embodiment of pure evil, for no clear reason. (Although ''Film/FireWalkWithMe'' [[BackstoryHorror reveals]] that there's a good reason the fan is imbued with evil: [[spoiler:BOB always switches it on before entering Laura's room to rape her]].) Of course, this is what happens when Creator/DavidLynch is your showrunner.
* The Hands of Blue in ''{{Series/Firefly}}'' have a very [[BrownNote unusual method of killing]]. It's one thing to use it on hated enemies, but they use it on [[InnocentBystander people who merely happened to learn too much]]. [[ForTheEvulz Mercilessness]] aside, it's hardly practical in a hurry; it leaves distinctively marked corpses behind, which almost [[StupidEvil defeats the purpose]] of eliminating witnesses; and the victims scream enough to alert the more important targets into running away. But it does help us understand why River fears them so much.

[[/folder]]

[[folder:Manga]]

* Creator/JunjiIto revels in this trope; ''Manga/{{Uzumaki}}'' has [[spoiler:a GeniusLoci EldritchAbomination made of AlienGeometries ([[HumanResources and people]])]]. It's pretty safe to assume standard biological requirements aren't even a factor.

[[/folder]]

[[folder: Music]]
* At the end of the song [[http://www.youtube.com/watch?v=cqVca_2WkkI Evil Food Eater Conchita]], Conchita [[{{Autocannibalism}} eats herself]]. This would be possible, if she had not left no trace, not even blood. How the hell that happened is subject to much WildMassGuessing.
[[/folder]]

[[folder:Pinball]]
* Creator/DataEastPinball's ''Pinball/TalesFromTheCrypt'' combines this with BlackHumor.
* Similarly, ''Pinball/{{Metallica}}'' combines images of skulls, flames, and death with jokes about electrocuting Sparky and [[ClusterFBomb a liberal dose of profanity.]]
[[/folder]]

[[folder:Religion and Mythology]]
* Dragons. Sure, [[OurDragonsAreDifferent they vary a lot]], but the best-known kind from European tradition are [[OurGiantsAreBigger huge]], [[ReptilesAreAbhorrent reptilian]], [[PlayingWithFire fire-breathing]], [[NighInvulnerable thick-scaled]], man-eating, flying, roaring, and AlwaysChaoticEvil -- often the FinalBoss of sorts. When cartographers put "Here be dragons" on unfamiliar areas, they sure didn't mean to [[SchmuckBait encourage]] exploration.
[[/folder]]

[[folder: Tabletop Games ]]
* ''TabletopGame/DontRestYourHead'' runs off this like crazy. The Mad City doesn't operate on normal logic, but instead functions as a surreal and bizarre world that will warp and twist things for the sake of horror. It uses all three methods: mixing the weirdness of the Mad City with almost normal inhabitants, and the perfectly mundane City Slumbering; lots of fairly amusing ideas for Nightmares that are cranked up to their terrifying potential, and stories that tend to end with the most terrible outcomes possible; topped off with lots of violence, truly bizarre and creepy entities with warped bodies, and many a hero slowly turning monsters themselves.
** The one supplement, ''Don't Lose Your Mind'', cranks this up even further by having a list of 26 new Madness Talents (one for each letter of the alphabet) that have built in methods of turning those that have them into Nightmares, each Nightmare being based off of a pun that somehow, despite the humor, ends up being horrifically creepy.
* The game designers responsible for the ''TabletopGame/{{Ravenloft}}'' D&D setting knew this trope as "The Bill Rule", naming it for design-team member William W. Connors. He summed up the concept by suggesting that Ravenloft [=DMs=] should, when faced with an in-game choice between options, always ask themselves: "Which would be ''scarier''?"
* Playing a mortal in ''TabletopGame/NewWorldOfDarkness'' (as distinct from an actual [[TabletopGame/HunterTheVigil hunter]]) will typically mean that encounters with the supernatural will be left unexplained and seemingly nonsensical. Supernatural characters generally have a better chance of figuring out what's going on (although there's always an exception...).
* ''TabletopGame/CallOfCthulhu'' has a strange mixed relationship with this. On the one hand, most of the monsters defy physics and evolution entirely, and are often made far more frightening for it. On the other hand, this makes sense because many of the monsters are aliens, and often extradimensional beings that don't follow normal laws of physics.
** Also weird with actual adventures, as they're typically set up as mysteries that do have actual explanations that persistent players can find, but player characters are so fragile and limited they're likely to die, or retreat, before uncovering much of the mystery. Most questions will remain unanswered, making it at least appear to be Rule Of Scary at work.
[[/folder]]

[[folder:Video Games]]
* ''Franchise/SilentHill''. Specific examples include the mannequin in ''VideoGame/SilentHill3'' that screams and has its head break off, complete with blood, when you happen to be looking the other way? No real reason for it, but it's creepy.
** Stanley Coleman. Finding his little notes for Heather is completely optional, and has no real impact on the plot, except to provide serious ParanoiaFuel.
* Half of the non-zombie creatures in ''Franchise/ResidentEvil''. [[GiantSpider Giant zombie spiders]] are creepy, even though you might wonder why a tarantula would grow several hundred times its body mass, but not other zombies.
** Oddly enough, it seems that only mammals can become zombified; the T-virus seems to just make insects, reptiles, and plants get bigger and more aggressive. Birds seem to just become more aggressive without becoming larger or putrefied.
** For that matter, the motives behind the actions of the Umbrella Corporation hardly ever make sense. It's as if their strategic planning sessions consist of people saying "Hey, I wonder what would happen if we injected zombie juice into one of ''these''!" Then again, this ''is'' a company where [[SolveTheSoupCans getting into the mens' room requires fetching the four parts to a family crest on the door, each of which is heavily guarded and hidden at a different corner of the map]].
** The pre-rendered backgrounds only allowed for fixed camera movement in the older games for the Playstation (and this was the case for many other PS1 games at the time). Many argue that this techinical limitation actually added to the scary atmosphere compared to the later games, as the player usually cannot see what is attacking them from certain areas. This applies similarly to the ''VideoGame/DinoCrisis'' games.
* Also, [=ReDead=] from ''VideoGame/TheLegendOfZeldaOcarinaOfTime''. Why these dried-up zombies wanted to dry-hump your face was never explained.
** Beneath the Well, and the Shadow Temple. Spontaneously sinking ghost ships, fake walls, floors, and platforms, [[InstantAIJustAddWater autonomous]] [[{{BFS}} giant guillotines]], an invisible boss that fights by beating on a giant bongo... the list goes on.
* ''EternalDarkness'' has a statue that turns its head to look at you, even when your sanity is at its highest. It serves no purpose, other than to creep you out.
* By and large, ''VideoGame/{{BioShock|1}}'' is not a horror game. It's a narrative-driven game with fairly standard baddies, albeit much more thought-provoking than most. That did not stop the developers from randomly throwing in scripted events where enemies suddenly appear right behind you or things that shouldn't be alive suddenly become so. The general lack of this elsewhere in the game and total subversion of logic is exactly what makes it so effective.
** The first shotgun is under a spotlight in a very dark room. Beside the shotgun is a dead splicer with surgical scissors in her eyes. If you grab the shotgun, the lights turn off making the entire room pitch black & you hear running footsteps. The spotlight turns back on but the other lights stay off so you can't see anything more than several feet away. Splicers start attacking from all directions. After you kill them all, you hear the footsteps again & the lights turn back on. You never find out who did that or why.
* ''[[VideoGame/FirstEncounterAssaultRecon F.E.A.R.]]''. How is Alma able to [[spoiler: rape the player character and become pregnant when she's an undead psychic ghost?]] Who cares, because it's absolutely ''terrifying.''
** Using her power [[spoiler: to reanimate her dead body, which was released from it's confinement]] at the end of the first game.
* TheSuffering. Why are those malefactors suddenly appearing and murdering everyone on the island and in the city?
** One theory in-game is that when too many atrocities are committed in one place, the monsters come. Thus, the possibillity the events of the game could happen anywhere. It's a small world after all...
* VideoGame/PokemonMysteryDungeon 2. How did those floating rocks in the future get up there in the first place?
* ''Franchise/{{Castlevania}}'' has been going on this for a while. Why does Dracula have [[NauseaFuel a giant rotting corpse hanging on hooks that's full of maggots]] or a laser shooting tentacle monster covered in naked corpses in his castle? Because it's disturbing, that's why.
* ''Fatal Frame'' has quite a bit of this. Why do ghosts have to get close if you want to inflict maximum damage? Because it's scary.
* While most, if not all, of the [[OurZombiesAreDifferent necromorphs]] in ''VideoGame/DeadSpace'' are pure ArtisticLicenseBiology, special mention has to go to the Hunter; that tenacious horror that stalks Isaac throughout certain portions of the game and is nigh unkillable due to its ability to grow back its limbs when they get chopped off. [[ArtMajorBiology Where does it get the extra mass to grow those limbs back?]] No one cares because it's terrifying.
* Or in ''VideoGame/{{Condemned}} 2: Bloodshot''. Why did those mannequins move to block the door behind you? Almost everything else in the game had some form of explanation, except [[http://www.youtube.com/watch?v=FPP5Ja7YNas that bit]]! SanitySlippage machines that are literally everywhere. It's just a hallucination. Now, why are SanitySlippage machines literally everywhere? AncientConspiracy. Why would an AncientConspiracy want SanitySlippage machines literally everywhere? This trope. That's why.
* Similar to the ''Condemned'' example above, what is up with the mannequins in NightmareHouse? Or the shadows in the hallway? [[spoiler: Are the zombies even real in the first place?]]. Doesn't matter, it's still damn scary.
[[/folder]]

[[folder:Web Original]]
* About the only consistent detail regarding the [[TheSlenderManMythos Slender Man]] is that he is [[UncannyValley freakishly tall, impossibly skinny]], [[TheBlank faceless]], and has arms that are in some way related to [[WhenTreesAttack tree branches]] and/or [[CombatTentacles tentacles]]. Oh, and he's [[NightmareFuel scary]]. Aside from that, nobody has quite the same interpretation of him, which just adds to his EldritchAbomination mystique.
* ''The Wiki/SCPFoundation'' basically defines this trope, often describing the effects of its various horrors in emotionless clinical detail, and just when you think it can't get any worse they [DATA EXPUNGED], forcing your mind to follow the list of [REDACTED] to the logical conclusion that █████████.
* ''{{Literature/Moonflowers}}'' is an UrbanFantasy that runs on this, as its main antagonists are TheWildHunt. Their leader (aptly titled the Hunter) wears a gigantic Irisk Elk's skull as a mask with burning red eyes, which he uses in an animalistic way by [[UseYourHead ramming his opponents with the antlers]]. He's tormenting a random American family for no particular reason, and is currently preparing for a ritualized serial-killing spree called [[HuntingTheMostDangerousGame the Fairy Raid.]] The only survivors of a past Raid were chanced upon by a deity, and nobody even knows what it's ''for''. Which fits with the source material, as CelticMythology is very emphatic on how dangerous TheFairFolk can be.
[[/folder]]

[[folder:Webcomics]]
* ''Webcomic/{{Annyseed}}'': Why does Count Tarrorviene have red scabby rings around his eyes? And how come Uncle Tarkwin doesn't have them, yet is the same age and species as Tarrorviene? Also, just how did they get that conveniently designed blood machine into that castle keep, and manage to plug it into his shoulder blades whilst he (most likely) fought for his very existence? It doesn't matter, it's creepy, so let it be.
[[/folder]]

----