[[quoteright:350:http://static.tvtropes.org/pmwiki/pub/images/Nightmare_Valley.jpg]]
[[caption-width-right:350:You're not perfect...]]

WesternAnimation/CourageTheCowardlyDog has a ton of freaky stuff in every episode, with some comedy to add a little NightmareRetardant in. However, some episodes tend to avoid the comedy angle, [[NightmareFuel and we end up getting these.]] In fact, these moments are so frightening that you may actually wonder why this show airs on the daily Creator/CartoonNetwork timeline instead of the Creator/AdultSwim timeline, which would actually fit there.
----
* The freaking pilot episode was already filled with terrifying scenes such as the Chicken from Outer Space '''breaking the neck''' of one of the farm's chicken (with a bunch of already dead chicken lying around) and Eustace's slow transformation into a Space Chicken (and he's LaughingMad through the entire process).
** Also, when Courage brings Muriel, it was just the Space Chicken and the [[NeverFoundTheBody bodies of the dead chicken]] had all dissappeared. We never find out what the Space Chicken did to them, as Courage frantically looks for them in the hay.
* There are plenty of scary episodes, but [[http://courage.wikia.com/wiki/Freaky_Fred_(episode) "Freaky Fred"]] stands out. He's obviously not right in the head, and he has sharp pointy objects within reach.
** What makes Fred stand out from all the other villains of Courage was that he had no malicious or murderous intent with any of his actions. He was just an insane man with an almost fetish-level obsession with shaving people against their will (incidentally, shaving IS a sexual fetish). Despite his urges ruining his only relationship, his career, and his life in general, he shows no remorse for what he's done. And the worst part is that he's probably the only Courage villain to "win", in that he succeeds in shaving Courage bare, save for his tail (because that would be ''weird'').
** The choir of children that can be heard singing when Fred starts shaving Courage... *shudder*
*** As a GeniusBonus, it's fairly clear that Freaky Fred is an {{Expy}} of SweeneyTodd.
** This episode is also unique in that it is told from the villain's point of view, so the viewer gets a better look inside Fred's mind.
--> '''Freaky Fred''': [[TheFourthWallWillNotProtectYou Hello new friend]], my name is Fred. The words you hear are in my head. I say, I said my name is Fred, and I've been... very naughty...
* The scene in the episode "Courage the Fly" where Eustace is chasing Courage as a fly. At one point, he gets Muriel's face stuck with fly paper and physically ''tears it off''.
* "Retuuuuurn the slaaaab...or suuuffer my cuuuuurse...", or [[http://courage.wikia.com/wiki/King_Ramses King Ramses]] from "King Ramses' Curse". To some, it's not even so much the voice, or his equally creepy {{Leitmotif}}, but the way he moves. The way they animated him makes him looks just like an UncannyValley reanimated corpse (not helping matters was that as opposed to the 2D animated characters, he's animated in CGI). And he just stood out in front of their house the whole time, never moving from that spot, but always watching them.
** In the beginning of "King Ramses' Curse", a [[TheSwarm giant black swarm]] chases the thieves who stole the slab. They bury it just in time for the cloud of doom to reach them. The camera pans to the side as they scream, and when it pans back, [[DeaderThanDead there's nothing left of the thieves or their car]].
* The episode [[http://courage.wikia.com/wiki/Perfect "Perfect"]] had the [[FanNickname Perfect Trumpet]] [[UncannyValley Thingy]], pictured above. This is most definitely the scariest thing to ever appear on the show.
** It's even better when you see it in motion. There are two reasons behind its "being creepier in motion": the vaguely off-key (or distorted, take your pick) background music, and the way the creature's eyes seem to imply that [[HypocriticalHumor it is somewhat of an incomplete experiment]], waiting for someone to put it out of its misery.
** The Perfect Trumpet Thingy was only the first in five nightmares Courage had to endure, the other four ranging from being genuinely creepy to [[TearJerker saddening]].
*** The second nightmare was essentially a DownerEnding parody of ''Film/TheWizardOfOz'', with the three main Oz inhabitants --the Tin Man, the Cowardly Lion, and the Scarecrow, all portrayed by Courage-- not getting either of the things they desired --to have a heart, to be brave, and to have a brain, respectively--, while The Wicked Witch of the West (also played by Courage) [[TheBadGuyWins watches them from her crystal ball, cackling at them]].
*** The third nightmare was [[NothingIsScarier a bunch of childish drawings rendered in CG, fluttering around a blue abstract space, while an ominous wind chime plays]].
*** The fourth nightmare (animated in stop-motion) was Courage on stage juggling bowls of soup in front of a audience. The audiences begins to laugh at him, upon which Courage realizes [[NotWearingPantsDream the bottom half of his body has been shaved]]. In embarrassment, he tries to cover himself, breaking his concentration and causing the bowls of soup to fall down and spill all over him.
*** The fifth and final dream, depicted in a crudely drawn, cut-out cartoon, is Muriel handing Courage a giant vase. Courage accidentally drops it...which causes Muriel to then ''shatter like glass''. Courage utters a anguishing "NO!" in horror as the entire dream similarly shatters into nothingness.
** Since "Perfect" is the series finale, you could say they saved the scariest thing for last.
** [[TheWikiRule The CTCD wiki]]'s name for the "character" in question is ''Eustace's Trumpet''[[note]](because of the saxon genetive in the URL, linking to the article is impossible, but you can look for it [[http://courage.wikia.com/wiki/Perfect in the already mentioned article for the episode)]][[/note]], that is, a nightmarish hallucination about the titular trumpet broken at the beginning of the episode. The trumpet's NightmareFuel potential is acknowledged in the article itself. Another creepy factor about the episode is the recurring theme of imperfection, [[AdultFear as it is]] - especially counting the "it's your fault"-ish way the line is delivered by the trumpet - [[FamilyUnfriendlyAesop likely to induce slight cases of inferiority complex among the more literal-minded viewers.]]
** [[SadistTeacher The Perfectionist]], not only does she torment Courage and give him the aforementioned sequences of nightmares, but when Courage finally accepts himself for who he his, ''she melts''.
* There's also a nightmare factory of an episode that is "Courage in the Big Stinkin' City". The whole episode is creepy, but it really cranks it UpToEleven when Courage enters the condemned apartment building to retrieve a package. The first two doors are rather silly (like an oncoming shark, or [[Franchise/{{Godzilla}} King Ghidorah]]), but when he opens the third door, he sees [[http://courage.wikia.com/wiki/The_Violin_Girl a girl (possibly 12 years old) playing the violin.]] She soon turns around revealing a freaky demon face and ''screams''!
** The FridgeHorror that is the monster behind the door from the same episode. Complete with skeletons around the room and a "help me" message written on the window. [[NothingIsScarier Even worse,]] ''[[NothingIsScarier we never find out what the monster is]].'' Also, the whole entire reason Schwick sent Courage to get the package with a squeegee inside was only because he needed to remove the "help me" message. Possibly to lure more victims without suspicion.
--> '''Schwick''': You wanna know what made these bones? [[YouDoNotWantToKnow You don't wanna know what made these bones.]]
** the fact that Schick is a giant cockroach is really nightmare fuel, cockroaches are scary looking to begin with and Schwick being a 5 foot tall cockroach is really nightmare fuel.
* "The House Of Discontent" is about as intentionally scary as the above examples. The premise involves an UncannyValley spirit harvest moon with a [[http://farm5.static.flickr.com/4027/4660441418_443e5147d4_m.jpg creepy white human face and dark soulless eyes]] trying to entrap and ''melt'' the Bagge family because Eustace failed to grow a plant to ensure his farmer status. Again, like Ramses, [[http://courage.wikia.com/wiki/The_Spirit_Of_The_Harvest_Moon the Spirit Harvest Moon]]'s {{Leitmotif}} is quite creepy.
** The voice was surprisingly deep and ominous as well, but the real thing that made this terrifying was that this was an eerily-out-of-place live-action black-and-white disembodied head, interacting onscreen with Courage and his owners. The fact that they were shown onscreen at the same time just seemed to add to the guy being convincingly scary, and the different styles were even more dissonant than the UncannyValley-CGI Ramses, who never shared the screen with any other characters.
* Any episode featuring [[CatsAreMean Katz]]. Katz has no qualms about killing Courage or anyone, and he seems to have no traces of comedy whatsoever. His {{Leitmotif}} might be as equally creepy accompanying his appearances.
** "A Night at the Katz Motel" is arguably his worst appearance, as his monstrous schemes at its worst take place in the middle of the night in a rundown motel. This episode is definitely not for arachnophobes.
** He's a SerialKiller and most of his episodes imply the family are only the latest in a long line of victims to fall into his traps...and the only ones to leave.
** He only targeted Muriel in one episode for the fact that her pies won first ribbon over his.
* The zombie director episode "Everyone Wants To Direct". This episode had a dark atmosphere with barely any humor, and the plot involving killing someone in a movie for real is all too real. Also, said zombies turned out to be past serial killers who managed to slay a dozen people ''[[WhatDoYouMeanItsforKids on a kid's show]]''.
* Some of [[http://www.youtube.com/watch?v=kusyDPg-wGY Courage's screams]] can be very terrifying for kids, especially when some body parts are deformed or organs come outside. Watch it, if you dare. By far the scariest is the scream from "Car Broke, Phone Yes".
* "Cabaret Courage". Getting dropped into [[WombLevel a room which looks like (is?) the inside of a human body]], talking to a guy that ''looks like'' an ulcer, then performing for that guy, getting dropped into some kind of green digestive-acid if you fail...
* "The Mask", which features a girl in a flowing white dress wearing a giant creepy doll mask (and a terrible, raspy voice) who beats the shit out of Courage due to a hatred of dogs and spies on them to look for any sign of hypocrisy. The back story about her friend's abuse by a pack of dogs is a (not even thinly) veiled depiction of domestic abuse and forced prostitution. ''Courage The Cowardly Dog'', a children's cartoon series with an episode revolving around an inner-city gangland drama.
* "Curtain of Cruelty" is definitely scary. The town turning from kind into rude and hateful. Forcing Murial to be bad bad by showing a video and having a mallet to hit a chained who was shivering. Then at the end of the episode, the gerbil is now smiling, and Eustace having seems milder in comparision, with the hamster even rubbing his head against him. It's not too scary until the gerbil has a angry face and pulls out a hammer, with the screen fading to black before you hear a thud sound.
* Eustace being consumed by foot fungus in "The Clutching Foot".
* It's Doc Gerbils World, It's Doc Gerbils World.
* ''The Great Fusili''. Specifically [[DownerEnding the ending]]. In it, Courage fails to stop Muriel and Eustace from being turned into puppets. Well, thank God that this show has a NegativeContinuity. However, this was originally going to be the last episode... There's also the nonexistent crowd, Fusili being turned into a puppet as well and the countless victims beforehand
** Courage reenacts his usual situation with them, implying that he had gone through some serious SanitySlippage by the episodes' end.
* The Evil Vet from the episode "Remembrance of Courage Past". At least Katz in some episodes, had reason to try commit atrocities, but the vet [[ForTheEvulz just seems to enjoy being evil]]. He's the one who not only directly traumatized Courage as a child, but was also responsible for [[ParentalAbandonment the disappearance of his parents]] and Courage ending up as an orphan until Muriel rescued him. Any villain from the cartoon pales in comparison to the evil vet.
* The episode 'Bad Hair Day' has a sequence where Courage goes into a building that farms humans for hair, and he sees dozens of humans hanging from rope on the ceiling... Most of whom have their eyes closed and are not moving.
* In "The Tower of Dr. Zalost," the titular doctor (who has, at this point, forcefully [[HatePlague made all of Nowhere depressed]]) chokes Courage onscreen. Later, after Courage creates an antidote for Zalost's cannon balls and destroys the fortress, a scorched, seething Zalost chases Courage back into the house, forcing Courage and a newly cured Muriel to hide in the kitchen. [[spoiler: Thankfully, Zalost [[TookALevelInKindness gets better]] immediately afterward.]]
* Though all of these can be nightmare retardant, due to a popular theory that everything happening in the show, due to courage's paranoia, massive fear of everything, doggy instinct to protect his family and possible psychotic neurosis and/or Schizophrenia. It may all be just in Courage's head. [[note]] One example, is when Muriel was kidnapped by giant vultures. But when he goes to save her, it turned out she was just babysitting the chicks. Muriel likely just went to a normal human neighbour to babysit, but Courage sees everything as monstrous. And being incredibly sheltered may be the reason why he doesn't take notice of any other houses in the neighbourhood... it wouldn't be totally out there for real-life dogs to not take much notice of homes that aren't theirs, if any notice at all.
* While not as iconic as a lot of scares and villains on the show (heck, the antagonists were just [[WellIntentionedExtremist Well Intentioned Extremists]]), the episode ''Courageous Cure'' is outright disturbing in its handling of body horror and InvoluntaryShapeshifting.
[[/note]]