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[[quoteright:350:[[VideoGame/MarioKart8 http://static.tvtropes.org/pmwiki/pub/images/demonbowser.png]]]]
[[caption-width-right:350: [[VideoGame/SuperPaperMario Your face is about to feel the burn!]]]]

Even Mario has run into his share of frights, as these examples will attest to.

The following examples have their own pages:

[[AC:Main series]]
* ''NightmareFuel/NewSuperMarioBros2''
* ''NightmareFuel/NewSuperMarioBrosU''
* ''NightmareFuel/SuperMario64''
* ''NightmareFuel/SuperMarioSunshine''
* ''NightmareFuel/SuperMarioGalaxy''
* ''NightmareFuel/SuperMarioMaker''
* ''NightmareFuel/SuperMarioOdyssey''

* ''NightmareFuel/CaptainToadTreasureTracker''
* ''NightmareFuel/DonkeyKongCountry'' series
* ''NightmareFuel/LuigisMansion''
* ''NightmareFuel/LuigisMansionDarkMoon''
* ''NightmareFuel/MarioAndLuigi''
** ''NightmareFuel/MarioAndLuigiPartnersInTime''
** ''NightmareFuel/MarioAndLuigiDreamTeam''
** ''NightmareFuel/MarioAndLuigiPaperJam''
* ''NightmareFuel/MarioKart8''
* ''NightmareFuel/MarioParty''
* ''NightmareFuel/PaperMario''
* ''NightmareFuel/SuperPaperMario''
* ''NightmareFuel/WarioLand'' series
* ''NightmareFuel/WarioWare'' series
* ''NightmareFuel/WarioWorld''
* ''NightmareFuel/YoshisIsland''
* ''NightmareFuel/YoshisStory''
* ''NightmareFuel/YoshisWoollyWorld''

[[AC:Other media]]
* ''NightmareFuel/TheAdventuresOfSuperMarioBros3''

!! ''General''
* While most platform video games have this as a feature, Goombas can cause damage and instant death just by walking into you.
* Several people are terrified by Boos. It pretty much all boils down to the fact that they [[ParanoiaFuel only chase you when you're not looking]]. It only leaves the door open to FridgeHorror.
* This series introduced the concept of spikes = instant death in video games. Good thing everything causes Mario to go into DeathThrows. Doesn't stop some kids from being scared by the thought of falling and getting impaled on spikes, and the resultant saturation of spikes in video games as a whole causes nightmare fuel filled scenes in video games where they DO impale you.
* The [[https://www.mariowiki.com/Skewer_(obstacle) Skewers]]. They debuted in Super Mario World, and have increasingly become even more terrifying due to graphical improvements. Especially when there are some that are ''incredibly large'' and/or ''incredibly fast''.
* The Thwomps. Their faces, especially in 3D games like ''Galaxy'', look extremely terrifying. Doesn't help that some of them are sentient in that they know you're coming and know when to drop down to try and crush you.


[[folder:Main Series]]

!! ''Super Mario Bros.''
* The first ''Super Mario Bros.'' gave us the MinusWorld, a world no man is intended to go to and has no escape, unless you count drowning to death or the reset button as a method of escape.
* If you let a Hammer Brother stay onscreen too long without killing him, he will [[https://www.youtube.com/watch?v=nih0xD0ZtTs chase Mario]].
* The castles in the first ''Super Mario Bros.'' game for the NES are really, really terrifying. There's just something about them; the [[NothingIsScarier lifeless]] [[DarknessEqualsDeath black background,]] the pointy-looking lava that doesn't move, the revolving sticks of fire, the fireballs that come as you approach Bowser's lair, Bowser himself (especially later on when he learns how to throw hammers)... and that music. [[http://www.youtube.com/watch?v=In8WfBgBEis THAT MUSIC.]] Some of the castle levels are [[GuideDangIt mazes]] that will repeat endlessly until [[TimedMission TIME RUNS OUT]] [[CriticalExistenceFailure AND YOU DIE.]] (or until you find the correct path)
** The famous [[http://www.youtube.com/watch?v=ox2Fjp9oeAI cave music]] probably creeped out more than a few kids.
* Good lord, the story behind this game. Bowser invades the kingdom and kidnaps Peach. That's all you get from the game itself. [[AllThereInTheManual In the instructions book,]] however, it's revealed that Bowser laid waste to the Mushroom Kingdom and turned the Mushroom Retainers that weren't kidnapped alongside their ruler [[TakenForGranite into bricks.]] The same bricks that Mario hits for powerups. And the reason why he kidnapped Peach was that she's the only one that can break the curse! These poor Toads [[AndIMustScream are probably aware of their position]], and would have likely stayed like that forever if they hadn't been separated by Mario.

!! ''Super Mario Bros.: The Lost Levels'' (Japanese ''Super Mario Bros. 2'')
* The firebar in C-4 that practically requires you to take a hit. If you're Small Mario, it's almost impossible to pass.
* 8-4 and D-4 both have two Bowsers in one castle (one of them is fake).
* The Hammer Bros from the original game? The ones that chase you if you wait? They don't wait this time around. They come after you IMMEDIATELY.

!! ''Super Mario Bros. 2 (USA)''
* The Hawkmouth in ''Super Mario Bros. 2'' (the one that acts as an end of level gate) scared the crap out of some in the end of World 7-2 when it ''flew off the wall and tried to chase them!''
** It was even creepier in the original ''Doki Doki Panic'', where it was some sort of tribal mask. [[http://www.nesmaps.com/maps/DokiDokiPanic/sprites/DokiDokiPanicSprites.html Look for it here, labeled (rather accurately) as "Evil Door."]]
* And then you get past the door to confront Wart -- and the music changes to this creepy, disturbing horror/techno mix that just messes with your concentration while you have to catch vegetables in midair and throw them into Wart's open mouth (as opposed to the other bosses where you just had to hit them with weapons).
* [[http://www.mariowiki.com/Phanto Phanto]]. Creepy pumpkin masks that guard keys; when you pick up a key, they come to live and move really fast and chase you.
** In remakes, World 1-3 in particular has a chamber with a key, a squad of phantos, and a giant Phanto face in the background. When you pick up the key, the background Phanto face's eyes light up {{red|EyesTakeWarning}}.
* Corrupting SMB 2 leads to some [[http://www.youtube.com/watch?v=OV-D1ggFUj8 horrifying results.]]
** Not to mention literally invoking this trope by [[NightmareSequence corrupting a game that's set in a dream.]]
** There are even some demonic symbols and evil nuances within the video, like a [[NumberOfTheBeast bunch of 6's]], and even images of a ''demon''.
* In some versions of the game, after Wart dies, there's some red under his eyes, almost like he's [[EyeScream bleeding from them.]]
* In the SNES and GBA remake, they made warping much, ''much'' eerier. When you enter the Warp Vase, a creepy tune plays in the background while [[InterfaceScrew the screen becomes distorted and fades to black.]] [[http://www.youtube.com/watch?v=2peaeVGjQ4E See the warps in the SNES remake here.]]

!! ''Super Mario Bros. 3''

* The [[https://www.youtube.com/watch?v=49A63nJiYsI mini-fortress music]]. It's quieter than the fortress music of ''SMB 1'', which gives it [[NothingIsScarier another brand of eeriness]].
* World 8 of ''Super Mario Bros 3''. Apparently, Bowser's home base is [[http://www.youtube.com/watch?v=lQCjaXRKoZQ Hell itself]]. The [[http://www.youtube.com/watch?v=DRMbsScm91Q gigantic, discolored hands]] that drag you down on certain tiles are especially creepy to a small kid. And if that doesn't scare you, the levels will because you are forced to play the levels without fail or you are sent back to the beginning of the tile section.
** The color limitations on the NES ended up making Bowser's castle look like (unintentionally?) some flash-tint structure with teeth at the front gate, like the castle is an organism. Compare this with the SNES version of SMB 3 where the details have been improved and the castle is less jarring, looking more like a regular castle-château with the top of the castle emulating the form of Bowser's upper-skull.
* The [[http://www.mariowiki.com/Angry_Sun Angry Sun]] made some too scared to play past World 2.
* Some were also afraid of the Podoboos in the World 1 mini-fortress.
* Chain Chomps debut in this game, and there's a quirk to their behavior that not many know about. If it [[https://www.youtube.com/watch?v=_4THDnt3wSA pulls on its chain]] 50 times or if the timer hits 160 seconds, it ''escapes''.
** Notably, Chain Chomps are inspired by an incident in which Miyamoto was nearly attacked by a dog.
* The Giant Fish that constantly chase you as you race against time to get to high-ground as the water level rises.... if you DON'T make it to high ground in time, or worse, '''fall''' in the water, these bastards will ''swallow Mario in one gulp'', no matter how big you are and, insta-kiling you. No chewing, no biting, just '''gulp''' and you're gone. Shiver.
* There were also some terrified by the Hot Foot in the first fortress of World 4.
* The laser-shooting Bowser statues in his castle.
* World 6's [[https://www.youtube.com/watch?v=c8LnHIODRMM map theme]] is pretty ominous and chilling compared to the other world map themes (save for World 8) in which gives off a feeling that something's bad is going to happen
* The first fortress in World 7, since the entire place is empty. No enemies whatsoever (barring the boss). Even worse is that one can see where the enemies would be, giving the feel that it was just suddenly abandoned.
* In the ''Super Mario All-Stars'' remake of ''VideoGame/SuperMarioBros3'', World 5's blue mini-fortress has both a lava floor ''and'' a ceiling. It's even more unsettling considering that in ''[=SMB=] 3'', lava isn't merely a harmless curtain for the top of a BottomlessPit; rather, touching it ''kills you instantly'', even if you're Super Mario. Or powered-up with the ''[[NotSoInvincibleAfterAll invincibility star]]'' for that matter.
* Boss Bass from ''VideoGame/SuperMarioBros3'' and ''VideoGame/SuperMario64''. ''Super Mario 3''[='=]s Boss Bass in particular has this habit of jumping right out of the water, ''snatching you right off the surface and swallowing you whole in one gulp''.
** And what makes it even more nerve-racking that by ''swallowing you whole in one gulp'', means that no matter what power-up form you're in, being swallowed and gulped is an instant death regardless.
* [=SMB3=] can be [[https://www.youtube.com/watch?v=2CIBrncUxwg corrupted too]], as LetsPlay/ProtonJon found out. The video is called "Super Mario Bros. 3: Nightmare Edition."
* In Worlds 1 through 6, each time you transform a king back to normal, he gives you a letter featuring some advice from Peach. Come World 7, however, and the letter instead comes from Bowser, who has informed you that he has kidnapped Peach (again), with his portrait on the letter and a ScareChord taunting you. Those who expect Peach's usual advice letters are in for a [[JumpScare nasty]] [[PlayerPunch surprise]] [[WhamLine out of nowhere]].

!! ''Super Mario World''

* In the final battle, Bowser is seated in a [[ClownCar hovercraft]] which is [[MonsterClown painted like a clown's face]]. After Bowser is hit a number of times, he flies forward, so that the screen zooms in on the hovercraft. Push the pause button at the right time, and there is a screen full of clown face.
** Then said [[ClownCar Clown-faced hovercraft]] in its ''final phase'' with its eyes being butch and angry while still [[PerpetualSmiler smiling]] as small veins pop out at the side of its head, all the while trying to pound and crush you.
* Mario/Luigi's death sprite. Maybe they went [[BlueWithShock red/]][[PaletteSwap green with shock,]] but to some, they just looked... odd.
* The Koopalings' defeat scenes vary. Morton, Ludwig and Roy fly around the screen and disappear but the rest meet a [[LavaPit lava-induced fate.]] While Iggy and Larry [[NothingIsScarier vanish]] [[KilledOffScreen off-screen,]] Lemmy and Wendy ''[[KillItWithFire sink into the lava]] [[FamilyUnfriendlyDeath and are burned alive!]]'' Youch!
** If that's not bad enough, [[spoiler: the epilogues of Morton, Ludwig, Roy and Wendy imply that [[HaveANiceDeath you killed them.]] On the other hand, they did return in later games, so the descriptions were probably added for shock value.]]
** Lemmy and Wendy's deaths are even worse in the GBA port of the game. Apparently someone thought it was a good idea to add a sound effect that sounds like a ''shriek of agony'' to them (along with Iggy and Larry).
* The big green bubbles in the Vanilla Ghost House freaked many out a bit. They were large, invincible, and always got in the way, and if even two closed in on you, you were screwed.
* The way secret keyholes grow so huge and then swallow up Mario is just plain freaky. The accompanying music only makes this worse. The GBA port makes it ''even worse'', because the music in that one has a louder bass line at the end that acts as sort of a LastNoteNightmare.
* The Big Boos from ''Super Mario World'' gave some fright as a kid, but the Monty Moles just continuously pop out and attack.
* The ''graphics'' in ''Super Mario World''. Most of the time, they were gorgeous. But many of the enemy sprites were just ''wrong''. The weird, hunched-over shell-less Koopas, the odd posing and so-smooth-it's-creepy animation of the Charging Chuck, the weird stick legs on the Koopa Kids... not to mention the fact the player's death sprite, it looks like Mario is ''[[EyeScream bleeding from his eyes]]!'' Accompanied by a ScareChord, no less!
* The [[UpdatedRerelease GBA version]] starts with a {{Nightmare Fuel}}-ish intro that ends with a LastNoteNightmare, as seen [[http://www.youtube.com/watch?v=LGUjSFSgv3M here]]; however, if you beat the game, [[http://www.youtube.com/watch?v=nQDKJu71pMY the result]] [[SugarWiki/HeartwarmingMoments makes up for it]].
* Those creepy looking Bowser statues in Bowser's Castle if you took one of the rooms, only to encounter a golden, animated one.
* Lava appears in some athletic/overworld levels. Except, due to palette differences, it's colored brown. Functions exactly the same, except, well, what is it? Mud? Melted piece of the ground? So bacteria-filled and acidic that bubbles come out?
** It's molten chocolate. That the stuff is only encountered on [[LevelAte Chocolate Island]] is something of a giveaway.
*** That may make it NightmareRetardant, but the fact that it still kills you raises a few questions. Like.. [[FridgeHorror what is in it?]]
* Big Boo in ''Super Mario World'' has a placeholder sprite for use before the final sprite is loaded. If seen at all, it's likely for a split second. However, it's an [[http://i.imgur.com/T7NFVzI.png empty, soulless emotionless face]] that for some falls right into the UncannyValley.
** Which technically, [[spoiler: just happens to be the same face Big Boo makes when facing it, just without being covered by the sprite's arms]].
* Sunken Ghost Ship, specifically, [[https://www.youtube.com/watch?v=ZgNdL3ffMOU&t=1m24s the loooooong drop that occurs at the end of the level.]] What makes it freaky is that the background is pitch black, meaning you have no frame of reference aside from the coins that you drop past. Then suddenly, after the super long drop, you either land on a small platform with the goal orb, or you land in the nearby water and have to jump out before the mines above fall onto you. The fact that this level reuses the dissonant, creepy music from the various Ghost Houses doesn't help. Finally, when you complete the level and uncover Bowser's domain, there is [[NothingIsScarier no music]] when you regain control on the world map. The lack of music also happens on subsequent clears of the stage.
* Wigglers, anyone? It's just so startling to see [[http://www.mariowiki.com/images/8/89/WigglerSMW.gif this adorable thing]] to turn into ''[[http://tinyurl.com/p4kzty8 this.]]'' The fact that Wigglers had no mouths in the game makes it even worse.

!! ''New Super Mario Bros.''

* In ''VideoGame/NewSuperMarioBros'', Bowser falls into lava in the first world. Not much different from what happened at the end of every single castle in the original ''Super Mario Bros''... until the game proceeds to show him ''desperately flailing in the lava, and emerging with all of his flesh melted off''. Totally unexpected and freaky as all get-out.
** Mario's next line, immediately after the whole debacle? "That's-a so nice!"
** This is actually a major plot point of the whole game, since it requires Bowser Jr. to take command of the entire Koopa Troop in place of Bowser's death.
** Later on in the game, [[spoiler:it turns out that he's ''still alive and continues to live on as a skeleton''. Which meant he actually got to ''feel'' his flesh burn off.]] Wow, Nintendo.
** In the final level, [[spoiler: Bowser Jr. uses a magic cauldron to restore his father to normal]].
* Hey, remember Unagi the Eel from ''Super Mario 64''? They made it into a regular type of enemy in this game. And also made a ''giant'', unkillable [[http://www.mariowiki.com/images/3/3f/NSMB_World_8-3.png version]] of it, which is easily the most terrifying enemy in the game.

!! ''New Super Mario Bros Wii''

* ''The final boss. Big time.'' It first starts off with a regular Bowser-on-the-bridge boss fight. Mario looks up to what appears to be Peach, a remix of [=SMB 1=]'s ending music playing... [[spoiler:before it starts LettingTheAirOutOfTheBand, unveiling Kamek in a Peach disguise. He gets on his broomstick and gives Bowser some magic...the ground starts shaking. Kamek looks down, wondering what's happening...and then, '''''WHAM!''''' Bowser ''springs up'', looking tremendously huge, his eyes ''glowing'' [[RedEyesTakeWarning a blood red]], and worst of all? Bowser is ''pissed. '''[[PunctuatedForEmphasis VERY. Pissed.]]''''' He starts chasing Mario down relentlessly in a mindless rage, with intense orchestral music playing and only becoming even more intense in the second phase...and just like Bouldergeist, it's his roar that really sells it. Like...''[[HellIsThatNoise holy hell.]]'']]

!! ''Super Mario Galaxy 2''

* Sorbetti, a giant rolling spiked snowball monster with a disturbing clown-like face and a really creepy high-pitched laugh. Because the fight planet is designed to look like the body to his head, it's even creepier.
* Cosmic clones in ''VideoGame/{{Super Mario Galaxy 2}}''. The ones in the previous game were simple Mario and Luigi clones that served as racing opponents. In this game, they follow your every action with a delay of a second or two. If one catches up to you or you bump into one, it hurts. You can't stop for even a quick breather or you'll get hit. And they keep coming. More and more of them get spawned every few seconds, leading to a seemingly endless chain of them. Even the nearby signs are afraid of what they can do. And worst of all, their corruption extends as far as ''[[spoiler:[[ThatOneLevel Luigi's Purple Coins]]]]''...
** They mimic their movements perfectly, a few seconds after they do. You touch someone on the shoulder, they touch them seconds later. You pick something up, they mime picking it up themselves. And if you stand still, they collide with you, exploding into dark energy at point-blank range. And until you, or possibly somebody else the comet is focusing on, finishes an arbitrary task, they spawn forever. Following you everywhere. And when you think about it, aren't the other comets also FridgeHorror? Just think of what happens when, say, the Red Comet gives one arbitrary person a time limit to do one task before dying.
* In several late levels, giant lava monsters suddenly rise up from out of nowhere and engulf your platform in their mouths. The last one is particularly memorable.
* In one galaxy, a group of penguins are out swimming, watched over by a couple of larger penguins. To get the non-secret star in that stage, you must hit a switch that causes the entire area to freeze solid. It's not just the surface; you can see them under the ice, frozen in midstroke. Congrats, you just caused the Ice Age.
** The penguins above the surface don't even seem to know, and the small penguin in particular is even ''happy'' that ice coated the land. [[NightmareRetardant But]] look even more closely and you can see the water still rippling and fish still swimming. And in the second main star mission the penguins are perfectly fine.
* In the Shiverburn Galaxy, if you change the camera to first-person mode and look toward the cliffs above you, there seems to be three mysterious shadowy figures on the cliff, watching you, and following you. You can read about it [[http://gonintendo.com/viewstory.php?id=126769 here]].
** [[http://www.youtube.com/watch?v=xu0vtkU02uM This shit. This shit right here.]]
** They're supposed to be trees. It doesn't help though, because they don't look at all like trees. And they have glowing eyes. Brrr.
** The file names? ''[=BeyondHellValleySky=]'' is where they reside, and ''[=HellValleySkyTree=]'' is the names; the ominousness of the trees were enough, but ''those names'' make them worse.
** The skybox implies that the cliff background is very far away, suggesting that these figures are somewhere between the size of a large hill to mountain-sized.
** They have since appeared in ''3D Land'' and ''3D World''. It seems they've taken an interest in the heroes... and the first trailer for Odyssey may imply that we may see these things again, this time up close and personal... [[spoiler: the tentacle.]]
*** The "tentacle" thankfully turned out to be a dinosaur tail.
* The swirling spirits in the background in the ghost levels.
* How about that black hole that spawns at certain places, waiting to suck Mario in if he falls off within range? the [[HellIsThatNoise sound too doesn't help matters at all]].
* Magmaarghs (a much larger version of Blarggs from ''VideoGame/SuperMarioWorld''). They're huge, hideous creatures made of lava who look incredibly deranged, with strange eyes and huge mouths, and when they try to collapse into Mario or Luigi, they make a very disturbing roar until they lose their form in the lava.
* Bowser himself, as he's immensely powerful and gigantic in this game. He nearly devours Rosalina and her starship, and creates a black hole that he's in complete control of.

!! ''Super Mario 3D Land''

* An EasterEgg: In the yard at the end of any ghost house, waiting long enough causes a ghostly figure to appear in the background just behind the fence and will vanish after a few seconds. This figure doesn't actually do anything and cannot be interacted with, but what makes it creepy is that the thing resembles the Shiverburn Galaxy figures. They're not trees. They're still watching. And they're getting closer.
** Even worse, it could be [[WebVideo/MarbleHornets Slenderman]], in a frigging Mario game. And as a bonus, it opens its mouth before disappearing, as if trying to scream at you... brrr.
*** The connection between the spirit and the ''[[=HellValleySkyTree=]]''... there's also a UFO visible if you wait a minute at 1-3. What other freaky stuff has Nintendo put in these games? Are they... are they trying a secret subplot told through weird Easter eggs?
*** Come to think of it, that UFO...we've seen a UFO like that before. Specifically, one that helped Bowser to airlift Peach's Castle in the first Galaxy game... Yes, others appear in later levels, but that first one that helped kick everything off--Bowser did ''not'' just happen across it on his own...
* The cosmic clones. They mimic Mario's quotes, but in a higher pitch with added distortion. When they say "Let's-a go!", it sounds like they're saying "[[CannibalismSuperpower Time to chow!"]]. Yikes.

!! ''New Super Mario Bros. 2''

* The Boohemoth, a massive Boo enemy, is bigger, chubbier, and his eyes don't look at all like the charming dot eyes that normal Boos have, but more into the UncannyValley. Although he only shows up in two Ghost Houses, he'll appear without warning with a ScareChord and chase you. He too stops and hides his face when Mario or Luigi looks at him, but every so often he'll peek and approach anyway. Thankfully, he only appears in two levels.
* In World 6-Castle and World Star-Castle, Mario has to make his way across a lava-filled platforming level. The kicker? He has to avoid the Koopalings' special [[{{TakenForGranite}} petrifying gaze]]. If he's not hiding behind a wall, one wrong step and he'll most likely freeze, and fall into lava.

!!''Super Mario 3D World''

* As cited from a Miiverse post, the Shiverburn figures are ''back.'' They can be seen through a reflection on a Clear Pipe Cannon on the last main level, [[spoiler:The Great Tower of Bowser Land]].
** The post? ''"Anyone remember those mysterious faces on the top of the cliffs in [[VideoGame/SuperMarioGalaxy SMG2]]? Or the mysterious face in the ghost house in [[VideoGame/SuperMario3DLand SM3DL]]? Look closely at the reflection in this photo. Tell me what you see."''
** It seems Nintendo is slowly trying to implement their own darker version of ''Literature/WheresWaldo''.
* There's also Motley Bossblob: a Koopa jester who summons BlobMonster creatures to transform into an enormous gelatinous AsteroidsMonster MonsterClown, complete with GlowingEyesOfDoom and a SlasherSmile. And it chases you around the stage, hopping around erratically in an attempt to crush you. Hope you aren't afraid of clowns.
* [[spoiler:Bowser re-kidnapping the Sprixie Princesses and using them to power Bowser Land.]]
* The [[AdvancingWallOfDoom advancing wall]] of Fuzzies in [[http://www.youtube.com/watch?v=cpeqzW6ltLQ Fuzzy Time Mine]]. Resembling a fuzzy black void with faces randomly and chaotically popping in and out, it consumes everything in its path.
* The [[https://www.youtube.com/watch?v=viYE2i4XZX8#t=58 music]] that plays in the final Captain Toad level sounds very chilling, especially in contrast with the more happy-go-lucky tracks in these stages.


[[folder:Misc. Games]]
* ''VideoGame/SuperMarioLand'':
** The way the enemies die is actually kind of creepy. Unlike the NES Mario games, where enemies generally flip upside-down and fall off the screen when you jump on them, here they lay on the ground, flattened and dead for a few seconds, before flopping off the screen. It gets worse with the Koopa Troopa analogues, which ''explode'' when they die.
** [[spoiler:The "Daisy"s]] at the ends of Worlds 1 through 3 of ''Super Mario Land'' [[spoiler:that are actually monsters]] can make the player jump a bit.
** There are bonus rooms with SpikesOfDoom. Coupled with the quiet bonus room music, Mario accidentally jumping onto the spikes and dying is pretty frightening.
* The [[https://www.youtube.com/watch?v=DhB8XG9_5Rc U.S. commercial]] for ''VideoGame/SuperMarioLand2SixGoldenCoins''. To some it may be Narm but before Wario was portrayed as the greedy character he is today, the U.S. portrayed him in a way that made most young gamers rather afraid of him. The commercials for Virtual Boy Wario Land and Wario Blast didn't help matters.
** The [[https://www.youtube.com/watch?v=qVeE9FhafaA&t=1m27s ending sequence]] to ''Super Mario Land 2''. Wario shrinks into a pointy-eared midget, [[BigLippedAlligatorMoment punts his shoe at Mario]], and runs off the castle balcony bawling. It became a bit more bearable in ''Wario Land: Super Mario Land 3'', when it was revealed that Wario has a "powered down" form a la Small Mario which looks very much like his diminutive appearance in the ending, but to a young child who doesn't know any better, it's easy to wonder: just what did Mario ''do'' to Wario to turn him into that strange little mutant? And [[FridgeLogic what happened to Wario after he seemingly jumped off a balcony on the highest floor of Mario's castle?]]
* The Thwomps from Bowser's Castle in ''VideoGame/MarioKart64''; it's that disturbing EvilLaugh. The green one in the cell is scarier for some reason. Luckily, they aren't scary in the Wii version's remake.
* The final stage of ''[[VideoGame/PanelDePon Tetris Attack]]'' for the SNES, where a Godzilla-sized Bowser rises out of a chasm at the end of a mountainside cave. [[OminousPipeOrgan Cue the sinister organ music]].
* The infamous ''VideoGame/HotelMario'' had some rather [[http://www.youtube.com/watch?v=PQoFaU2iqxY unnerving music.]]
** Also in Hotel Mario, you must never hide in doors during boss battles. While this does work for regular enemies in normal levels because they can't enter the door and hurt you, the Koopa Kids (except Wendy) or Bowser himself will enter the door you're in, come back out, and burp out Mario's hat, strongly implying that they ate him. The silence before the "lose a life" music does not help.
* ''Mario Teaches Typing 2'', like ''Mario 64'', featured the floating disembodied head of Mario. Unlike the ''Mario 64'' version, this one goes back and forth between cracking jokes and being amusing, to being just plain unsettling at times.
* The GBA puzzle game ''Mario vs. Donkey Kong'' features a relatively realistic 3D rendering of Mario facing off against cartoony Thwomps and Shy Guys, and is brought up at this point in the page due to its ''Galaxy''-like series of disturbing death animations. The default animation (for example, stepping on spikes or touching a Shy Guy from the side) has Mario tilt briefly before he falls face-first into the floor ([[EyeScream or spikes!]]) and stops moving. Then there's the specialty animations for dying to a fiery or electrical attack, which don't pull any punches about how terrifyingly painful it must be for poor Mario.
** There are [[http://www.youtube.com/watch?v=cAfOX4Jv9xw three different "death" tracks]] in the game's BGM. While the first two apply for "standard" deaths (the second is used for getting burnt by lava), the third is used for the most horrifyingly painful and gruesome (for Mario standards, that is) death animations, such as getting squished by a Thwomp, falling from a high place (with Mario falling ''on his head'' as a result) and, last but not least, getting ''electrocuted to death''. In fact, you can tell the various deaths apart by listening to the different pitches of Mario's variants of his classic "Mamma mia!". The first is "standard", the second is "exhausted", and the third is "a mixture of pain and horror".
* ''Mario Tennis'' was the game that debuted Waluigi. In his debut, Waluigi, not only was pretty creepy looking, but made extremely weird noses all of the time, almost like a psychopath groaning in pain or delight. Whenever he scored, his celebration would have him [[GlowingEyesOfDoom making his eyes glow and flash purple]], all while bearing the [[SlasherSmile demented grin]] frozen into his face. The glowing eyes, to this day, remain unexplained.
* In ''Mario Power Tennis'', when Yoshi wins a trophy, there's an animation in which Luigi brings it to him. [[MeatOVision Things go awry]], and in the end Yoshi has swallowed Luigi. He doesn't get spit out. There isn't even an egg. [[OffscreenInertia He never escapes.]]
** Another one involving Luigi, Luigi delivers a trophy to Shy Guy. While walking toward Luigi, Shy Guy suddenly trips and his mask falls off. Only Luigi sees what's under his mask, and he is terrified. What ''is'' under a Shy Guy's mask!?
*** Actually, Luigi already knew before then. In Luigi's Mansion [[spoiler: you can remove the masks from Shy Guy ghosts revealing their heads to be completely hollow]]
* The end of ''VideoGame/{{Mario Is Missing}}'', when Bowser is defeated, may scare some young children. You don't fight him, he comes out of nowhere and is shot out of a cannon, innocent enough. It's cartoony. Then he falls into the ice, freezes up, is covered in snow, then shatters.
** Also one of the versions you have to rescue Film/KingKong. The image you get of him is his fist wrapped around the entire EmpireStateBuilding. Something that big is too terrifying for words.
* In [[VideoGame/MarioStrikers Super Mario Strikers]], we have Bowser, who is portrayed as a giant [[ImplacableMan implacable koopa]] who wreaks major havoc on the field with shells and bombs whenever the "Bowser Attack" options is on instead of comic relief. When that occurs, his entrance would be accompanied with a short, gritty rock n' roll riff or a ScareChord. Worse is that [[ParanoiaFuel you don't know whether when or if he will ambush anybody in his way.]] Even when he becomes playable in Charged, it does little to dampen the terror, considering not only does he often turn on his own teammates if he's on a winning streak, his gloves have ''blades longer than his own claws'' attached to them. Perhaps even worse is [[http://www.youtube.com/watch?v=_un7fv8JW04&t=29s the silhouette he gains when using his Mega Strike.]]
** Also, one of Peach's screams when she is electrocuted sounds like a realistic interpretation (i.e. screaming bloody murder) of feeling that type of excruciating pain in contrast to some of the other screams. Think about how she and the others feel in a more realistic way after that.
** The Mega Strikes can be this. Almost ''everyone'' gains an unsettling silhouette, and there's a look of utmost fury on (most of) their faces. Makes you wonder: ''what the hell is going on to cause this?!?''
* [[http://www.youtube.com/watch?v=VSN6KS-z3p8 The Game Over theme]] from ''VideoGame/SuperMarioKart''. What's scary is that if you lose all your lives, the screen darkens, your character vanishes, then "GAME OVER" drops in ghostly-like letters, with that nightmarish music playing in the background.
* A meta-example, but ''Mario Kart Arcade GP'' holds a dark secret; [[http://tcrf.net/Mario_Kart_Arcade_GP three test images, two of them are innocent stuff, but the third one is a photograph taken from the September 2004 Beslan school hostage crisis of all things!]]
* ''VideoGame/SuperMarioRPG'':
** There's a room in the Sunken Ship with a Mario clone that seems pretty harmless, like any other NPC. Except that said Mario clone TURNS INTO A GREAPER out of nowhere, and you enter battle.
** When you initially arrive at Seaside Town in ''Super Mario RPG'', there is definitely something off about the place. The townspeople all look identical, and display disturbing behavior, like stopping mid-sentence to quietly converse with each other, and watching you sleep. It eventually turns out that a Smithy Gang member named Yaridovich took over and impersonated the entire town.
** Smithy, himself. Imagine a cyborg-bearded-giant-king-mechanical being, with [[MoreTeethThanTheOsmondFamily More teeth than the Osmond Family]], and a couple of replaceable heads, each just as creepy as the original.
** The factory's basement where the final battle takes place, the floor is made of nothing but several Smithy's heads, and some particularly interesting ones seems to be looking at the player. It would be harder to beat him if those [[http://vinesauce.booru.org/index.php?page=post&s=view&id=7112 eyes were glowing]]...


!! ''Super Princess Peach''

* In Bowser's Villa, there are a couple of segments that contain several faceless Peach statues and a HUMONGOUS Thwomp that takes up the entire background. Before it opens its eyes to scan the area, you have to copy the poses the statues are in. If you fail to do so, ''you'll be sucked into his gaping mouth.'' Of course, you'll only be sent to the beginning of the segment, but still...
* The wall of Langolier-like Boos that you can only escape from while crying because it makes you run faster.
* Perry devours baddies to recover the Vibe Gauge. If there are no enemies nearby, one can stand still for a few seconds, cuing an idle animation where Perry ''latches onto Peach's head'', to her vocal displeasure, regaining Vibe Gauge that way.
* The Mad Boos and Mad Big Boos, which look positively AxCrazy.
* In Bowser's Villa, there are several segments where you constantly need to avoid a pair of mechanical claw-like things flying in from the sides. Get caught, and you're treated to Peach being helplessly trapped in them [[StrappedToABomb while they begin a countdown to explode.]] There's nothing you can do if you get caught, unless you mash the buttons on the D-pad for dear life.

!! ''Mario and Sonic at the Olympic Games''

* During the Hammer Throw event in ''London 2012'', most of the characters will let out a [[ScreamingWarrior yell when preparing to toss the hammer]], but Daisy's yell in particular sounds more like a blood-curdling scream of pain. It sounds so eerily realistic!



!! ''Super Mario Bros. The Movie''
* Daniella and Daisy's kidnappings are played to scary effect, and as far as the residents of Brooklyn knew, they and the other girls were missing and probably dead.
* Koopa coming on to Daisy. With his face and tongue getting... [[UncannyValley less human]]. (Early drafts suggest he was attempting to ''rape'' her.)
* The Goombas and Koopa Troopas are huge behemoths with tiny heads and flamethrowers.
* Lena's head motions and hisses invoke the UncannyValley, and she's intensely jealous of Daisy.
* Koopa snapping and attacking Luigi after politely asking them for the rock. He looks like he's trying to crush Luigi's head or gouge his eyes out.
* The brothers dissolving between dimensions. Mario was conscious of the fact that he ''disintegrated''.
* Koopa's TransformationRay, especially in the deleted scene where a guy gets devolved into slime.
* According to Mojo Nixon, who played Toad, Dennis Hopper's performance as Koopa legitimately scared him during the scene where Toad de-evolves. Toad freaking out as he's strapped into the chair ''wasn't'' acting.
* [[GasMaskMooks The Snifits]], due to those weird noises they were constantly making.
* Lena [[spoiler:stabbing Yoshi]] after trying to kill Daisy.
* Goomba!Toad getting set on fire.
* Lena shoving a guy out of the way by grabbing his face, then getting electrocuted when she dives for the meteorite piece seconds later.
* Lena [[spoiler:being fossilized by the meteor energy]].
* When the two dimensions start to merge, Koopa's twin towers -- one of which looks half-destroyed (actually, it's not finished construction yet, but the visual effect is the same), and the other of which has a glowing stylized "K" on the side that looks like, depending on how you see it, either an explosion or a gaping hole -- replace the World Trade Center towers. This scene can be nightmare fuel to especially survivors and family members of the victims of the September 11th 2001 Terrorist Attacks.
* When the dimensions start to merge, what is the first thing Koopa does when he arrives in New York City (specifically, Brooklyn)? He unintentionally de-evolves [[spoiler: Scapelli]] (due to Mario, his intended target, jumping sideways out of the way to avoid it) into a monkey! Granted, [[KickTheSonOfABitch the son of a gun had it coming]], but still, it is kind of scary to be de-evolved into a monkey.
* The JumpScare of the Tyrannosaurus lunging out.
* Koopa devolving into slime.
* There's a short scene in the night club where a female Dinohattenite swallows a worm that she's using like a cocktail olive. Except that the worm ''pleads for mercy as she drinks and then lets out a dying scream when she swallows it''. It's a textbook BigLippedAlligatorMoment, coming out of nowhere and being ''seriously'' freaky. It's not made any better when you realise it's a ShoutOut to ''Film/TheFly1958''.
* Bob Hoskins had a '''''terrible''''' experience during filming, suffering numerous injuries from '''''being stabbed four times, being electrocuted, breaking a finger, and NEARLY DROWNING!''''' He and John Leguizamo would get drunk on set to try and forget how miserable the experience was.
* The city itself is pretty terrifying, especially for anyone expecting the bright, cheery Mushroom Kingdom of the games. It's dark, fungus-infected (and the fungus is ''sentient'', albeit helpful), and full off strange devices and hostile people. It also has more than a few things in common with a police state, given how Toad is arrested for singing an anti-Koopa song and prisoners are hung from the ceiling in cages. Oh, and at least one form of punishment is for prisoners to be de-evolved into hulking monsters to work for the very people who did this all to them.

!! Animation

!!! ''The Super Mario Bros Super Show''

* "Love 'Em and Leave 'Em": Queen Rotunda, an {{Expy}} of [[Disney/AliceInWonderland the Queen of Hearts]], ordering the Marios to be executed, yelling "[[OffWithHisHead Off with their heads!]]". Then, Mario tries to intervene, causing the queen to ask ''why he still has his head!''
* "Count Koopula" has creepy looking and sounding GiantSpiders that wear [[GasMaskMooks Snifit]] masks.
** Many of the horror-themed mooks in that episode definitely qualify, including the Koopa Troopas changing into [[OurWerewolvesAreDifferent wereturtles.]]
** Koopa's vampire alter-ego, Count Koopula, is perhaps his most menacing and terrifying.
* Dr. Koopenstein's brain scanner in "Koopenstein" along with Koopa turning into the Koopenstein Monster when he gets too close.

!!! ''The Adventures Of Super Mario Bros 3''

Has [[NightmareFuel/TheAdventuresOfSuperMarioBros3 its own page.]]

!!! ''Super Mario World''

* The Koopas revealing their trap in "Send in the Clown". Several Thwomps block the exits as the cavepeople and the Marios try to escape before they are forced into a cage where some terrifying hungry dinosaurs await them.
* "Ghosts R Us", where Yoshi must save Mario, Luigi, Princess and later Oogtar from a haunted house. Their captor, Wizardheimer, isn't exactly Mr. Nice Guy. Probably because [[AccidentalMisnaming they keep screwing up his name]].
* Koopa threatening to feed Oogtar to a dinosaur in "The Night Before Cave Christmas".
* "King Scoopa Koopa": Luigi, Yoshi and the cavepeople turning into Chickadactyls was scary enough but the real nightmare fuel was when [[NightmareFuelStationAttendant King Koopa]] wanted to turn them into KFC-like food and ''eat them''! Neither Mario (who dislikes eggs, and was only eating the fries and coconut shakes) nor the princess (who doesn't trust any of the food that Koopa was making) ate the eggs, or otherwise [[TheBadGuyWins Koopa would have won!]] Koopa's line really seals the deal: "One more day and it will be too late. Your friends will go from the fried egg to the fryer. And the next stop is the frying pan!" If [[SpaceWhaleAesop this was meant to]] [[ScareEmStraight keep kids away from fast food,]] [[{{Anvilicious}} they did a good job of it!]]
* The monstrous Piranha Plant in "A Little Learning". First, it grows at an ''alarming'' rate when Oogtar feeds it fertilizer. Then, it leaps out a window and chases Koopa, snapping its jaws threateningly at him. Koopa, Hip and Hop hide behind a tree only for the Piranha Plant to find them and [[SwallowedWhole swallow them whole!]] Yoshi eating it immediately afterward doesn't exactly help matters.
** Hip's project causing the school to explode like an actual volcano.
* Luigi [[IFellForHours falling into the chasm]] in "Mama Luigi", all while [[SkywardScream screaming at Mario for help.]] Following that, his trip through the Lava Pits where two menacing-looking T-Rexes threaten to eat him and Baby Yoshi.

!! Other

* [[http://pixeloo.blogspot.com/2008/03/super-real-mario-world.html This "realistic" Mario image]] is UncannyValley personified.
* Everything has eyes. You can't go anywhere without being watched.
** ''[[http://brawlinthefamily.keenspot.com/comic/142-stumble/ Brawl In The Family]]'' noted this.
* A fear of heights as well as death by falling makes playing ''Mario Galaxy'' and ''Mario 64'' terrifying sometimes[[note]]since Galaxy had falling into an endless abyss/sucked into a black hole deaths and 64 had falling damage[[/note]].
* The German Club Nintendo comic ''Super Mario in Die Nacht des Grauens'' [[labelnote:(ENG)]]Super Mario in The Night of Horror[[/labelnote]] features a [[http://www.mariowiki.com/File:DNDG_CN4.jpg zombie Princess Peach]] with creepy black eyes and a pale, cracked face.
* [[http://web.archive.org/web/20150729082440/http://www.suppermariobroth.com/post/57227938568/creepy-nurse-peach-art-from-the-german-club This]] image of Nurse Toadstool from the German Club Nintendo magazine has ''horrifying'' SkintoneSclerae.
* [[https://www.youtube.com/watch?v=HPPLGfk6YdI The underratedly demonic You Lose theme]] from ''Mario Hoops 3-on-3''.