Someone or something is tormenting our heroes in their sleep, be it one of their regular menaces or something new. At best, the recurring nightmares are causing them sleepless nights and impairing their performance in the real world. At worst, they find that any injuries in the dream world carry over to the real world and their lives are in serious danger. Either way, the protagonists must find out how to stop their night-time tormentors. Subtrope of Talking in Your Dreams. May be mistaken for Bad Dreams, Anxiety Dreams, Dreaming of Things to Come, Dream Spying, or Dreaming of Times Gone By. Indeed, those tropes can be used by the attackers. See also Primal Fear, Nightmare Dreams. Not to be mistaken for Your Favorite, unless you are a Nightmare Fetishist. Not to be confused with I'm Your Worst Nightmare (which is just the phrase).
open/close all folders
Anime and Manga
- This is the ability of the Death 13 Stand in JoJo's Bizarre Adventure, made worse by the fact that they forget the experience upon waking up. Your Mind Makes It Real is in effect, which Kakyoin exploits by using a pocketknife to carve the Stand user's identity (the baby that's traveling with them) into his arm with a pocketknife, which transfers to his arm in the real world.
- In part of Nightmare Inspector, Tsukishiro, Hiruko's rival baku, alters people's dreams to make them more terrifying, and tastier to eat. Mind you, most of them were already having nightmares already, but Tsukishiro made them much worse.
- In a side comic to Space Battleship Yamato, Desslok's exiled wife and daughter have the power to psychically torment people, which they usually do when their victims are asleep. Their usual modus operandi is to make them hallucinate family members begging for help and warning the Star Force of danger, though Nova saw three-fingered hands grabbing her.
- Ashley gets up to a lot of this in his first appearance in Hack/Slash. Unfortunately for him, he isn't tough enough to survive Cassie's mental landscape.
- Batman villain Scarecrow has used every possible variation of this trope in his lengthy career. Sometimes his involvement is left as a surprise, and his motives vary from revenge to simply studying the effects of fear.
- When Scarecrow uses his fear toxin on The Joker, though, he accomplishes nothing at all. The Joker just finds fear (even his own) to be funny.
- The Monkey King, a demonic entity from Saga Of The Swamp Thing, fed off the terror of children by assuming the form of their deepest fears.
- Sinestro Corps members are initiated by experiencing their worst fears so that their rings can absorb their fear energies. After this, they have the ability to weaponize the fears of others.
- The second story arc of IDW's My Little Pony Friendship Is Magic comic sees the Mane Six being tormented by evil spirits with nightmares revolving around their worst fears, like Twilight's fear of disappointing her mentor Princess Celestia, or Applejack being afraid of letting down her family.
- In Avengers: The Initiative, Terrance "Trauma" Ward's powers enable him to transform into the object of someone else's deepest fears. He hates this ability and has very little control over it. He has this power because he is the son of the Dream Demon Nightmare.
- In Project Superpowers, Mr. Face gains the ability to manifest everyone else's greatest fears. After coming back from the Urn, he tries to avoid being around other people.
- Warlord of Mars had a one-shot comic where John Carter suffered a vision where he is back on Earth and placed into a nuthouse, believing that all his adventures in Mars were all mad delusions, spending years trying to find a way back, losing some of his limbs in the process and nearly going insane. The whole thing was a nightmare caused by a rare Martian monster known as "balor", that puts its victims through their worst fears.
- Paperinik New Adventures:
- Paperinik's Extransformer Shield is equipped with a holografic psyco-captor, a device that reads an enemy's worst fear and then projects a hologram of it. For whatever reason, Paperinik never uses it.
- Evronian Super Soldier Trauma has psychic powers that make you relive your worst fears and nightmares until you are about to break... At which point, being an Emotion Eater like all the Evronians but far more powerful, drains all the fear and turns the victim into a Coolflame. The only thing capable of opposing this power is genuine courage, as in overcoming fear, that will short out his powers.
- In the relaunch story "Might And Power" the Evronians fielded a whole army of mutants with a weaker version of this ability, using them as slave drivers for prisoners they needed not Coolflamized yet.
- Korinna Ducklair has a very similar ability to Trauma, only far more powerful. She uses it both to defend herself and effectively brainwash people or implanting psychic suggestions.
- Ultimate Sleepwalker: The New Dreams has a rather gruesome variant with Psyko, whose madness beams force anyone affected by them to constantly relive their worst nightmares over and over again. What makes this stand out is that Psyko not only commits Mind Rape on his victims, but he can also use their bodies as People Puppets in making them do his bidding even while they're hallucinating. Oh, and he can also do all this when you're wide awake.
- Deadlock does this to Spyro and Cynder in The Legend of Spyro: A New Dawn during the "Restless Night" chapter. She makes them both experience rather frightening nightmares, Cynder reliving killing her mother as Dark Cynder and Spyro dreaming he turned into Malefor. Cynder's is worse because she sees the blood of the dragons she killed as Dark Cynder dripping from her claws.
- Getting Back on Your Hooves: Checker Monarch repeatedly does this to Trixie and her friends throughout the story as a form of Mind Rape. Following her Engineered Public Confession, she snaps completely and casts a spell to force them all asleep so she can do this again and break them completely. Thanks to a Lucid Dreaming trick Trixie taught them all earlier in the story, they're all not only able to fight back, but they kick Checker's ass.
- Jewel Of Darkness: There's one chapter during the Jump City Arc where Mumbo releases an Eldritch Abomination that attacks the Titans by attaching to them in their sleep and making them live out their worst fears — Jinx relieves her Dark and Troubled Past and near-suicide (with the strong implication of making her go through with it), Beast Boy becomes a horrible monster and kills his friends, Cyborg is turned into a full machine and is used as a weapon, Starfire relives her own Dark and Troubled Past, and Robin's is not shown (but makes him nearly strangle Jinx when he wakes up).
- In the My Little Pony: Friendship Is Magic Fanfic Moonlight, this is what every pony affected by the mysterious being that is putting ponies to sleep has happen to them, from things that are affecting them recently to nightmares in their past.
- In the RWBY fic Various Vytal Ventures chapter "Hide and Seek", a demonic being called Nightmare attacks several characters in their dreams. Ruby is forced to watch everyone else's nightmares, unable to help them. Weiss is trapped in a Hall of Mirrors that repair themselves when smashed, and her reflections come to life, saying she's a failure and will always be alone. Blake turns into a sort of werecat and attacks her friends, while she's still conscious but unable to control her body. Yang suffers a broken leg and loses her powers, leaving her helpless when she's attacked by a swarm of rapier wasps. Jaune turns into a helpless baby and his friends cruelly abandon him. Pyrrha is attacked by a swarm of snakes and bitten several times, paralyzing her just as a Taijitu Grimm arrives and prepares to eat her. Ren is attacked by his own mother, who calls him a disappointment and tries to kill him. Nora becomes invisible, inaudible, and intangible, and nobody seems to remember her. Velvet is beaten up by Team CRDL, who then prepare to gang rape her. Sun is forced to wear a clown outfit and perform in a circus, where the audience jeers and subjects him to Produce Pelting. Penny is strapped to a chair and a Mad Scientist starts to disassemble her robotic body. Fortunately, Ruby finds the strength to reject her fear of being unable to help her friends, which pulls everyone out of their nightmares and into her dreamworld. Everybody then kicks Nightmare's ass.
- The fanfic Time Fixers Nicktoons Of The Future has Darry getting possessed by Nightmare Juju, who has the ability to make people live out their worst fear, and can absorb dreams from those who are asleep, turning them into nightmares.
- The A Nightmare on Elm Street movies are probably the best example of this trope, with hapless teenagers being tormented and slaughtered by the dream-walking, One-Liner-spouting psycho-killer Freddy Krueger.
- In Dreamscape (1984), psychic Tommy Ray Glatman can kill people by inserting himself into their dreams and scaring them to death. Eventually the Hero learns how to do it too and kills Glatman and his boss the same way.
- In Embrace Of The Vampire, the vampire visits a college freshman in her dreams as a way to seduce her.
- In Animorphs book 6, Jake had an unexplained vision of a thing with a Big Red Eye. In the much-anticipated book 26, it was revealed that since then, he'd been having nightmares that replicated the experience perfectly, except that at the end, the BRE said "Soon." And then, the BRE was finally identified as being that universe's closest analogue to Satan.
- In the Discworld novel Hogfather, a band of intruders in the home of the Tooth Fairy are menaced (and in many cases, killed) by a number of scary things from their childhood. One is literally swallowed up by darkness, another is devoured by a wardrobe with a creepy face in the woodwork, a third is chased off (and presumably killed) by a "Scissor Man" (read: a man made of scissors who threatens children that suck their thumbs), a fourth is attacked by an exaggerated version of a bully they knew in school, and one dies of a heart attack after being menaced by a giant version of his domineering, abusive mother.
- The Chronicles of Narnia: The Voyage of the Dawn Treader included an area of ocean known as the Dark Island "where dreams come true". In this case, "dreams" meant dreams; not "wishes" or "daydreams". And "dreams" includes "nightmares".
- It was so awful that the lord who had spent several years there begged King Caspian to swear that he would never permit anybody to ask him about his experiences.
- That was retconned in recent editions claiming to restore the "original text" intended by C.S. Lewis. That lord now asks to never be returned to the island (the point being that in this text, unlike the other, it's clear that the island still exists).
- In the movie, the Dark Island terrorizes the people of the ocean and is apparently pure evil. It tempts and creates the fears of those who want to destroy it.
- In Grave Peril, book three of the Dresden Files, a ghost torments (and occasionally drives insane) its victims in their sleep. It eats Harry alive.
- Harry Potter:
- This is the power of the boggart species. The fears seen range from mundane (Hermione being told off by a phantom teacher for failing a test, while Ron's six-foot-tall spider causes quite a few screams) to poignant (Molly Weasley seeing a vision of her dead children, plus Harry). Harry's worst nightmare, interestingly, is the Dementor - a creature that spreads fear by its very presence, meaning his worst fear is fear itself (when Lupin thought it'd be Voldemort, whose boggart is apparently his own corpse, so terrified is he of death).
- Boggarts are defeated by laughter: boggart!Snape ends up dressed like Neville's grandmother, while Seamus' banshee loses her voice.
- H.P. Lovecraft set a whole series of stories (tied to the Cthulhu Mythos) in the Dreamlands, or some such name. It's no surprise he used this trope, in one story where a tale is transmitted — somehow — to the narrator concerning a man who cannot wake up, and is chased through his dreams by Eldritch Abominations. The narrator concludes by stating that he is afraid of what he might find if he visits the address mentioned in the story.
- In Through the Ice by Piers Anthony and Robert Kornwise, the heroes were magically attacked with dreams of their respective worst fears. After several failed attempts to defend themselves, the only successful method was to "yield to it," make the nightmares worse, and then (with the help of their telepathic team-member) hurl them back at the sender.
- In the Wheel of Time series, this is the effect of dreams that touch Tel'aran'rhiod. Just brushing against it while dreaming of a dangerous experience can result in bruises or scrapes; actually being inside it when you dream of dying will kill you. Fortunately, few people are ever fully inside without a special power, but sometimes you can be sucked in by someone who has the ability to do so. One poor fellow is made to simply fade away into nothing.
- Occurs in the original Dragonlance Chronicles series when the Heroes of the Lance penetrate the Nightmare of Silvanesti. Most of the heroes perish in ways that would arguably reflect their worst fears—Sturm dies a coward, Flint dies when his old age catches up to him, Tika dies after her own ineptitude gets her killed, Goldmoon dies when Mishakal seems to desert her after she loses her faith, and so on. They get better after Raistlin defeats Cyan Bloodbane, the dragon who was causing the Nightmare.
- There is a short story which deals with a young boy being brought to see a psychiatrist for some sleep-related problem. During a hypnotism session, the boy explains that there are some sort of aliens that commit Mind Rape on him while he sleeps and leave him a horrible wreck afraid to fall asleep. The psychiatrist gives him the drive to order them away and the next morning, he's able to sleep peacefully. Then we find out that the aliens have moved on to feeding on the psychiatrist. While he prepares to get rid of them, the story ends with the implication that they'll just move on to someone else.
- In Robert E. Howard's Conan the Barbarian story "Black Colossus", Yasmela denies this trope, knowing that her lady in waiting will assume it's true; she really was awake when the apparition—an Eldritch Abomination Stalker with a Crush—menaced her.
- In Shadows of the Apt, Ucteberi does this to the Bee-Queen.
- In Jasper Fforde's ''Well of Lost Plots'', Thursday Next is tormented by dreams of wartime in the Crimea that are being inflicted by Aornis, a "mindworm" that is acting through Thursday's memories of the physical person. She didn't think that maybe Thursday had worse nightmaries.
- Cas from Anna Dressed in Blood unknowingly has these. He initially thinks that they're from the stress of being a ghosthunter, but then he realizes that the ghost that killed his father has been causing them.
- Subverted in the Coldfire Trilogy. Damien Vryce willingly asks for Gerald Tarrant to cause these so that the vampiric Emotion Eater can feed off the fear. Of course, it makes for poor feeding since Vryce wisens up to the artificial nightmares easily enough.
- Hester is terrified of Palimpsest and takes a number of pills to keep from seeing it.
- Buffy the Vampire Slayer: In "Restless" all of the Scoobies are almost killed in dream sequences by the First Slayer. Buffy defeats her by ignoring her.
- An episode of Charmed pits the Power Trio protagonists against their worst nightmares come to life after the Demon Of The Week gets his hands on some Sandman sand.
- A first season episode featured a serial killer who developed a way to enter the dreams of women who rejected him. Killing them there meant they died in real life.
- In season 2 of Heroes, Molly Walker is tormented by what she calls "the nightmare man," but she refuses to talk to anyone about it. The nightmare man is later revealed to be Matt Parkman's father, who locks her down until Matt beats him in a mental battle.
- In Kamen Rider Double, the Nightmare Dopant torments people in their dreams, putting them into comas. In order to battle him, the protagonists transform into Double and then go to sleep, since the transformation places one person's consciousness in another's body. This creates an interesting fake-out moment, as a dream version of the character appears in addition to the real one, something the Dopant didn't anticipate.
- In Lost Girl, a dark fae Mare who is a Dream Weaver infects people and fae with these in order to feed off their fear. Bo, the protagonist, has nightmares revolving around being abandoned and alone which is not a surprise given her background.
- In the Stargate Atlantis episode "Doppelganger", an entity jumps from an alien crystal to Sheppard, then from him through various cast members, causing vivid nightmares starring a sociopathic Sheppard. The entity only scares people at first, until killing the psychiatrist Dr. Heightmeyer in a falling dream where she hit the bottom. The sociopathic Sheppard which only acted on everyone else's worst fears (Heightmeyer's fear of heights, Keller's fear of Alien etc.) eventually re-entered his own consciousness and its revealed his worst fear is himself which proceeds to taunt him about his failures, self-loathing and beat him to a pulp.
- In a similar episode Sheppard hallucinates his arch enemy Kolya kidnapping and torturing him for hours. Again it turns out his worst nightmare isn't Kolya but his own inadequecies and that he believes he deserves to suffer. There's a reason Sheppard is the Broken Ace.
- In the Star Trek: The Original Series pilot episode "The Cage" (later recalled by Spock in "The Menagerie"), the illusion-casting Talosians attempts to bring the captured Capt. Pike to heel by momentarily creating the agonizing illusion that he is in Hell. Furthermore, they warn him that he if doesn't behave, then they'll dig deeper into his mind for the really nasty stuff!
- In Superhuman Samurai Syber-Squad episode "To Sleep, Perchance to Scream," a series of Dream Within a Dream situations is eventually revealed to be the Monster of the Week tormenting him via his alarm clock (talk about Everything Is Online!) once we get down to reality. Then, it turns out the whole thing was All Just a Dream. Or Was it a Dream?.
- The Eyesac monster in Power Rangers Ninja Storm has the ability to put collars around peoples' necks that forces them to experience their greatest fear.
- The Sabrina the Teenage Witch episode "Fear Strikes up a Conversation" played with this trope. Sabrina, nervous about giving a speech in front of all of Westbridge High, uses a spell to remove her fear—only for it to become a living shadow that followed her everywhere. While she was immune to its effects, it caused everyone around her to become overly paranoid: Libby, terrified of never winning another beauty pageant, constantly applied makeup; Harvey, worried about being injured, clung to walls rather than walking normally. To defeat her fear, Sabrina's Quizmaster leads her on a kind of Journey to the Center of the Mind, where she encounters her worst hidden fears, including being take advantage of for being too nice, not getting into a good college, and being outed as a witch. She conquers them all and goes through a door to discover her deepest fear...delivering her speech. She does so successfully, and overcomes her fear—who turns out to be Steve Allen. And once having overcome her fear, she then transforms herself into her Quizmaster's worst fear a clown to torment him in a bit of well-earned payback.
- In an episode of The Troop, "Wrath of the Wraith", the team hunts a wraith in an abandoned hospital, and learn the hard way that wraiths can create paralyzing visions of their victims' worst fears. Felix's is an evil clown, Hayley is shown thousands of unfinished, overdue assignments, and Jake sees his friends in mortal peril and him not being able to save them.
- Our Miss Brooks: In "Friendship", Miss Brooks suffers from a referring dream where she's being attacked with a knife.
- In the Dungeons & Dragons universe, there is an epic monster known as a dream larva, a major threat usually sealed away in some other dimension. It is either a literal child of a god of dreams or a god's nightmare that has been so powerful that it absorbed a spark of his power and become sentient. In either case, its essentially Freddy Krueger on steroids, capable of messing up dreams of entire worlds at once. It also has a reality-warping power to assume the shape of everyone's worst nightmares simultaneously, so most mortals get heart attacks just seeing it.
- Guess what? The only spell that can summon this abomination is an Epic spell, thus (almost) on par with spells that can, say, rains apocalypse from the heavens to an area as large as a city. Yeah, this creature is this trope, Exaggerated.
- In 3.5's Monster Manual II we get the Nightmare Beast which, surprise, can induce horrific nightmares to any intelligent creature from a distance. Add Its immense size, the ability to trample smaller creatures and some pretty frightening spells and you have a monster made for inducing nightmares regardless of whether you are awake or asleep.
- In several game editions, the spell Phantasmal Killer creates a mental illusion of its target's worst fear, which has the potential to strike them dead with terror. Weird is a high-level variant that affects multiple targets.
- More simply and literally, there's also the Nightmare spell (in some editions the reversed version of Dream), which lets its caster play this trope straight against a sleeping target at a distance.
- A known symptom of latent psychic abilities in Warhammer 40,000. If it doesn't result in an unbelievably horrible death from the creatures of the Warp, it usually results in an unbelievably horrible death at the hands of the Inquisition.
- This is the main source of action in Catherine. The hero, Vincent, as well as a number of other men in his town are plagued by nightmares where they have to navigate up massive, constantly-disintegrating block towers while being chased by enormous monsters which are tailored to their own psychological traumas. And if you fail, you die in real life. Matters are further complicated by the fact that none of the men can remember their dreams when they wake up.
- In Pokémon, Darkrai can trap its victims in a neverending nightmare. Whether or not there is malicious intent depends on the game.
- There's also the move Nightmare, which inflicts significant damage on sleeping opponents. Darkrai's ability, Bad Dreams, is simply a less powerful version that automatically activates.
- In several routes of Tsukihime the protagonist has dreams of himself attacking and killing people, only to see the victims being reported in the news the next day. He actually ends up going temporarily insane from it, as he is convinced that he is the killer, although it's actually the Big Bad's doing, as the protagonist's consciousness is only drawn into his mind when sleeping due to the connection that runs between them.
- The exception to this is Kohaku's route, in which it isn't a dream — nor was the pavement discussion you had with Roa/SHIKI that led to them leaving town.
- In the side-story/sequel, Kagetsu Tohya, the protagonist is actually stuck in a recurring dream of repeating days in which he periodically has run-ins with his worst nightmare (his amoral sociopathic killer split personality) and later his interpretation of Death (a hybrid demon from his traumatic early childhood).
- World of Warcraft has Potions of Nightmares, which "puts the imbiber into a slumber where they face and defeat their darkest fears." Doing so regenerates the character's HP and mana.
- In the Vanessa Vancleef encounter, Vancleef poisons you with the Nightmare Elixir, causing you to experience the worst nightmares of the instance's previous bosses; Glubtok and Fire, Helix Gearbreaker and spiders, Foe Reaper 5000 and electrical shocks and Admiral Ripsnarl's memories of when the worgen curse made him kill his family.
- Gauntlet: Dark Legacy has this as a name of a level in the Jester's realm.
- The Eater-of-Chains from Fallen London does this. If it bites you in the real world, it will attack you in your dreams from then on.
- Fall in Parallel Dementia has dreams where multiple supernatural entities (called "Nightmares") try to influence her and each other. Once she was convinced to sleepwalk to the edge of a second story balcony and climb on the railing before she was woken up.
- When Torg, Bun-Bun, and Kiki went on the Wayang Kulit vision arc in Sluggy Freelance, they each had to face their worst fears manifested. Torg saw himself bring death to all the women in his life and gradually become a demon. Bun-Bun relived his mother's murder, unable to intervene. And Kiki was given a PB&J sandwich that she couldn't cut the crust off of.
- Subverted by Bun-Bun not running away or cowering in fear, but instead getting pissed off like usual and beating the crap out of the Shadow trying to scare him.
- In Arthur, King of Time and Space, Arthur's reaction to his worst nightmare is "Still, things could be a lot worse".
- Whateley Universe example: Bladedancer, the Handmaid of the Tao, was attacked through her dreams by mages of The Black Tong (who are on another continent and are performing dark necromantic rituals to power this attack). Too bad for them that Whateley Academy has its own patrol for the astral realms.
- SCP Foundation: SCP-959 has this as his main effect. He's actually a nice guy.
- American Dragon: Jake Long had this as an episode, the nightmare was only released because Jake tried to cheat on a test.
- In The Powerpuff Girls episode "Power-noia", Him visited the girls in their sleep and tormented them with the aforementioned worst nightmares.
- This is inversely done to the Sand Man via the girls when he gets fed up with constantly having to put people to sleep and get no sleep for himself, thus leaving him to decide to just force everyone to sleep at once. The girls find out that they have the power to communicate through dreams and use this to give the Sand Man so many nightmares that he never wants to sleep again. Yeah...
- Batman: The Animated Series:
- Zigzagged in "Perchance to Dream". The Mad Hatter's dream machine traps Batman in an inescapable Dream, but it's actually what he would consider a perfect life. His parents are alive, he's engaged to Selina Kyle - who isn't Catwoman - and someone else is Batman. However, when he realizes that it's all a farce, he refuses to live a lie, and leaps off a building, causing himself to wake up, as his mind cannot perceive a scenario where he is killed. When he confronts the Hatter and demands to know why, the villain breaks down in tears and admits that he wanted to give Batman his own dream life just so that he never appears in his own life ever again.
- Played straight in "Over the Edge"; after being doused with the Scarecrow's toxin in a fight, Batgirl fell into a deep slumber, and in her dreams, believed her own death occurred in the battle, and then was forced to watch her greatest fear played before her eyes, a war between Batman and her father as a result of it, all because she had kept her heroic identity secret from him until that point.
- In the Justice League episode "Only A Dream", the Justice League faces John Dee, AKA Doctor Destiny, a criminal accidentally given Psychic Powers by an experiment, who uses his new abilities to torture and kill his ex-wife in her dreams, then goes on to torment our heroes. He bites off a bit more than he can chew, though, when he taunts Batman, who's powering through with willpower and coffee.
Doctor Destiny: Coming here was the mistake of your life. See, the closer I am to someone, the stronger I get. I'll be able to enter your brain, even if you're wide awake.
Batman: My brain's not a nice place to be.
- Doctor Destiny also existed in the comics, with much the same MO—however, here, it's notable that he gained his powers from a device which was retconned to be powered by a special ruby... that originally belonged to Dream of Neil Gaiman's The Sandman, before it was officially split off from the main DCU.
- Lilo & Stitch: The Series:
- One of the experiments (Experiment 300/Spooky) could turn into the thing a person feared the most. It even got to Nani by disguising itself as Scary Black Man social worker Cobra Bubbles and threatening to take Lilo away from her.
- A later episode has an experiment (Experiment 276/Remmy) that can invade dreams and turn them into nothing but nightmares. It nearly does this to Lilo, but Stitch, Pleakley and Jumba intervened.
- The DuckTales episode "Nothing to Fear" saw Magica DeSpell threatening Scrooge and company with a magic raincloud that caused a person's worst fears to manifest. At first, the trope was Played for Laughs; thus, goofy neighbor kid Doofus was threatened by a school bully, the nephews had to deal with a video game villain and their overbearing math teacher, while Scrooge was threatened by bill collectors who wanted to take away everything he had, including Huey, Dewey, and Louie. Then, the story became Darker and Edgier, as the characters experienced more serious fears of rejection and abandonment.
- SpongeBob SquarePants:
- A whole episode was devoted to this. SpongeBob travels into other main characters' dreams and messing them up, making them become nightmares. Even Patrick is annoyed by his best friend's presence in his dreams.
- Well, he doesn't necessarily cause nightmares, but he certainly gets on everyone's nerves. Plankton and Sandy's certainly count as nightmares, while Squidward's is an arguable case. The rest are just really annoyed.
- And he wasn't really trying to cause problems. But he is SpongeBob...
- Patrick wasn't really annoyed either, he was just sitting there on the ride doing nothing.
- In The Tick, Mr. Mental controls Tick by submitting him to his worst nightmare: having a dayjob in an office.
- An episode of Hercules: The Animated Series had Phantasos using a shroud similar to his brother Morpheus to give people bad dreams.
- In the G.I. Joe episode "Nightmare Assault", Dr. Mindbender tortures the Joes with these. His scheme is foiled by Low-Light, who has had nightmares about his abusive father all his life and is pretty used to it by now.
- In the Jonny Quest: The Real Adventures episode "Thoughtscape," Jeremiah Surd tries to stop Jonny and Benton from saving Jessie by trapping them in their own worst fears: Jonny's is being a disappointment to his father, and Benton's is his family dying because of him.
- Extreme Ghostbusters had "Fear Itself", an episode devoted to a ghost that did this. Turned out it was a defense mechanism - the ghost was very small and very scared of everything. The crew don't bother to bust it, since they realize that it was only trying to defend itself, and could literally do nothing else to hurt anyone that could overcome its fear-constructs.
- From The Legend of Korra, Big Bad Amon is this to Korra.
- In an episode of Superfriends, a demon called Sleep does this to Superman and Batman. Superman was placed in a world where everything was made of kryptonite, and he collapses in agony. Batman was falling from a building into a monster's mouth, and every time he tried to grab something to break his fall, it would crumble to dust and he would continue falling. Wonder Woman enters the dream and saves them.
- In the season 3 premiere of My Little Pony: Friendship Is Magic, King Sombra turns out to have set a trap like this to prevent anypony else from getting to the Crystal Heart. Twilight Sparkle falls into it, and sees a vision where Princess Celestia angrily tells her she failed her test and she should just give up on her magical studies. Spike manages to free Twilight, only to fall into it himself and be treated to a vision where Twilight tells him he's not needed anymore as her assistant and tries to send him away.
- The Tantabus, which appears halfway through season 5, is a creature of dark magic that travels from dream to dream, turning each dream it invades into a nightmare and growing in power as it does. The true source of its strength is the guilt of its creator.
- The Simpsons parodied the A Nightmare on Elm Street series in a Halloween special episode in which the children of Springfield were terrorized in their nightmares by the deceased Groundskeeper Willie. After Bart, Lisa and (mainly) Maggie defeat him in a dream, they wake up and are confronted by a very much alive Willie, who makes scary faces for a few seconds, until he's forced to turn around and chase the bus he just arrived in, shouting "Wait! Wait! I left my gun on the seat!"
- Xiaolin Showdown had the Shadow of Fear. While the Wu initially was limited to dream invasion and hallucinations, it ultimately had the ability to give the fears physical form. While controlled by Jack Spicer, he brought the Dragon's worst fears to life: a Killer Doll for Kimiko, a jellyfish monster for Rai, Clay's Granny Lilly, and a giant, monstrous squirrel for Omi. At the end of the episode, Omi pays Spicer back by making him face his biggest fear: Getting trapped inside the toilet as a toddler.
- Ultimate Spider-Man featured an episode in which Spider-Man helps Dr. Strange and Iron Fist stop the demonic Nightmare, who has cast a sleep spell over the world and is feeding on everyone's worst fears. White Tiger's is failure, Luke Cage's is being unable to protect his friends, Nova's is bunnies, the Doctor's is his spells being useless, and Iron Fist's is being unworthy of his power. Nightmare thought that Spider-Man's was what happened to Uncle Ben, but failed to realize that, unlike Batman, Spidey is defined, rather than haunted, by his past.
- As shown in the Trollhunters episode "Where Is My Mind?", with the Pixies responsible for making the ordeal akin to a Mushroom Samba.