History NightmareFuel / Left4Dead

** If the transformation of Lt Mora was any indication, all of the infected see normal humans as "monsters", thinking they're still normal while everyone else has turned into zombies. Now think how they see you, the player, wielding a shotgun can completely dismember them in a few shots, coming straight at you, almost unstoppable...

*** The Hunter, an almost human-like zombie but with abnormal leaping distances and inhuman aggression should he be able to catch a survivor. What makes it worse? The Hunter has no eyes. If you look underneath his hood, you can see two empty eyes sockets with dissolved skin around them. This means the Hunter tracks you by sound and scent alone, meaning you can't hide from him.
*** The Smoker, a horribly boil-covered emaciated man that can strangle you with a 50-foot-long tongue;
*** The Boomer, a horribly bloated (and also boil-covered) man (and sometimes woman in the sequel) whose attack obscures your vision with green vomit while triggering a wave of infected that will target you specifically;
*** The Witch, a crying girl with very long claws that can knock you down in one hit and kill you in two more;

** The Dark Carnival menu theme has a JumpScare too, the one that is [[FreezeFrameBonus hard to spot at first]]. If you look at the left ticket toll, sometimes a zombie with [[GlowingEyelightsOfUndeath white glowing eyes]] will show up in a distance before leaning back out of the view. Quite a nasty surprise for many players, especially since no other Infected has their eyes shine so ''bright''.

** No Mercy: The AbandonedHospital in the last two stages is rather chilling. You'll see that the entire staff failed to find a cure for the infection and became infected themselves.
*** A rather chilling case of realism is at work here. Hospitals are the places sick people often congregate in, so an infection like this will spread like a wildfire among those with already weakened immune systems.

** Death Toll: This campaign features the infamous "Church Guy". A survivor who was bitten by an infected and [[ParanoiaFuel has gone mad]]. Hearing him repeatedly say [[MadnessMantra "Better safe than sorry"]] like a deranged psycho is horrifying. He even scribbled those words on the wall more than a hundred times.

** Blood Harvest: What's worse than going through the woods at night? Going through the woods with zombies at night. The dead cows near the farmhouse are also rather scary.

* Until around 2004 there were in the entire recorded history of the Rabies virus (which the infection is a strain of) exactly TWO survivors, one of which was a Greek man several thousand years ago. Now thanks to modern medical science (and a quick google search) the number has increased to a whopping SIX with there being no verification for all but one of the latest batch of survivors actually having the virus in the first place.
* Rabies can take up to 2 years before it progresses to the first stage despite it normally taking 2~12 weeks? To top all of it off, the symptoms listed for rabies include anxiety, insomnia, confusion, agitation, abnormal behavior, paranoia, terror, hallucinations, progressing to delirium, etc. So the infected are probably fully aware of what's going on with the virus actively amping their emotional state up to eleven which (judging from the descriptions I've been seeing of the Special Infected) correlates to the behavior. Witch is Anxiety and possibly terror. Hunter is paranoia so it's trying to get you first possibly because it thinks YOU are the infected one. Tanks are obviously aggression. Jockeys are hallucinations and general delirium. So on and so forth with the rest being a mixture.

** What happened to the possibly hundreds of children that [[{{FridgeHorror}} were there at the time]]?

** The Dark Carnival menu theme has a JumpScare too, the one that is [[FreezeFrameBonus hard to spot at first]]. If you look at the left ticket toll, sometimes a zombie with [[GlowingEyelightsOfUndeath white glowing eyes]] will show up in a distance before leaning back out of the view. Quite a nasty surprise for many players.

** The sequences at Millhaven are pretty terrifying. Soldiers witness the infected for the first time and are rapidly overrun, with their defensive positions being silenced one by one on the radio. With the last survivors becoming more and more panicked.

** The Sacrifice: This is it. You've made it past a hospital full of infected patients, crashing your helicopter, met an infected psycho, went through a bombed airport and got through the zombie-filled woods, surely this will not be difficult. It won't be. The wrecked boats near the starting point are bad, but the end has you [[HeroicSacrifice sacrifice one of your teammates]] to restart the generator. What's worse, [[spoiler: the sacrifice is considered canon, as shown by Bill's dead corpse in The Passing]]

** Dead Center: From the moment you walk out of the safe area and begin making your way down a burning building filled with fireproof zombies you know that this game is gonna be a lot more intense than the last one. If you're lucky you may even run into [[spoiler:Ellis's hero turned zombie, Jimmy Gibbs Jr.]] in the abandoned mall at the end.
** The Passing: A new DLC campaign. Pairs you up with the original survivors from the first game at the beginning and end. That doesn't stop this campaign from being freaky! From along stormy streets above and to the extremely dark sewers below you'll encounter some really creepy stuff. Survivors that went out into the world fully armed... but not immune! The Witch's wedding which even the survivors agree is frighteningly weird and when you've met up with the survivors and been given your task you may decide to that room just to the right of the lift when you exit. What's Inside? [[spoiler:The dead body of Bill!]] Making this campaign not only horrifying but a TearJerker as well!

* Because some people have talked about mods... "One 4 Nine" takes place in the Nevada Desert, in and around Area 51. What's disturbing about it is that multiple saferooms are destroyed, however, one specific one in the first chapter has a blood pool with bones and human body parts surrounding it. Later on, you find almost the same thing, but with one difference. It has parts of human faces in it. Also, the finale has you activate a huge black monolith to get out. However, after you activate it, it causes the screen to switch colors, albeit very slowly. [[spoiler: What happens after the "rescue" is coming, is both hilarious and terrifying: The survivors are apparently transported into an alien spaceship.]]

** The Charger, a man with an abnormally large right hand and abnormally thin left hand. Like the Hunter, it has inhuman aggression too, but instead of abnormal leaping distance, the Charger instead charge with his right hand striking toward a group of survivor, stunning non-targets and catching the target to be pounded into submission.

** The Spitter, a woman with horribly burned off and open jaw that able to somewhat spray corrosive goo at incredible distances.

** The Dark Carnival menu theme has a {{JumpScare}} too, the one that is [[FreezeFrameBonus hard to spot at first]]. If you look at the left ticket toll, sometimes a zombie with [[GlowingEyesOfUndeath white glowing eyes]] will show up in a distance before leaning back out of the view. Quite a nasty surprise for many players.

* In a (somewhat) meta example, the Survival gamemode descriptions for the different chapters on the Left 4 Dead Wiki, because of the fact that they all consist of “what if” scenarios that could realistically happen in real life.
** Dead Center: Atrium. Once the doors open, find some gas cans. Simple, right? What if there ''are'' no gas cans? Now you’re stuck in a mall filled with zombies with no way out.
** The Parish: Bridge. Get across a bridge to a helicopter extraction. All four of you have guns. Easy, right? What if you got there, only to find out the pilot died from the zombies? What are you gonna do now?

** Let's not forget [[https://www.youtube.com/watch?v=F_7C8oN2klY Hard Rain's]] theme, which uses a creepy, almost [[UncannyValley unnatural]] banjo along with a very faint kick beat. Truly, this is what you'd probably hear in literal hillbilly hell.

* A savvy player can predict where Tanks are likely to spawn and know when one will strike well before it does thanks to the music clues. So what happens when the music doesn't play and instead of coming after you, the Tank sits and waits quietly for you in a dark room? [[BringMyBrownPants New pants happen]], [[WrongGenreSavvy that's what.]]
** Also, sometimes when you don't get the music cue, you can still tell if there's one nearby... because you can hear them ''breathing''... Opening a door and finding a Tank there is bad enough, but standing in front of a closed door and hearing his panting clear as day is [[PunctuatedForEmphasis so. Much. Worse.]]
** Even worse when the breathing noise doesn't even show up in the subtitles. You hear the breathing, but since the subtitles don't say anything, it may be just paranoia. You walk on, hear it again... now you're almost pissing yourself every time you walk around a corner, but again, no Tank, no music, no subtitles, but you hear the freaking noise. Eventually, you decide that it was just paranoia and move on, and wham, there it is, right in front of you.
* Let's not forget about the campaigns themselves

* Rabies can take up to 2 years before it progresses to the first stage despite it normally taking 2~12 weeks? To top all of it off, the symptoms listed for rabies include anxiety, insomnia, confusion, agitation, abnormal behavior, paranoia, terror, hallucinations, progressing to delirium, etc. So the infected are probably fully aware of what's going on with the virus actively amping their emotional state UpToEleven which (judging from the descriptions I've been seeing of the Special Infected) correlates to the behavior. Witch is Anxiety and possibly terror. Hunter is paranoia so it's trying to get you first possibly because it thinks YOU are the infected one. Tanks are obviously aggression. Jockeys are hallucinations and general delirium. So on and so forth with the rest being a mixture.

* The 4th chapter of the custom campaign ''[[https://steamcommunity.com/workshop/filedetails/575682109 Dark Wood]]'', which takes place right after you blow up an underground lab and find yourself in a prison that's literally, ''literally'' straight out of ''Franchise/SilentHill'' (the textures on the walls are pretty much lifted from ''Silent Hill 3''). In a campaign that already was advertising itself on its creepy factor, the 4th chapter turns it UpToEleven by having the entire map be one dark, long, rusty labyrinth as you and your friends dread everything that might be coming around the corner, complete with the really unsettling ambience of ''screams'' in the background. It really feels like you've gone deep enough to be in Hell.

* The 4th chapter of the custom campaign ''[[https://steamcommunity.com/workshop/filedetails/575682109 Dark Wood]]'', which takes place right after you blow up an underground lab and find yourself in a prison that's literally, ''literally'' straight out of ''Franchise/SilentHill'' (the textures on the walls are pretty much lifted from Silent Hill 3). In a campaign that already was advertising itself on its creepy factor, the 4th chapter turns it UpToEleven by having the entire map be one dark, long, rusty labyrinth as you and your friends dread everything that might be coming around the corner, complete with the really unsettling ambience of ''screams'' in the background. It really feels like you've gone deep enough to be in Hell.

** [[AdultFear What happened to the possibly hundreds of children]] that [[{{FridgeHorror}} were there at the time]]?

*** The Spitter, a woman with horribly burned off and open jaw that able to somewhat spray corrosive goo at incredible distances.
*** The Charger, a man with an abnormally large right hand and abnormally thin left hand. Like the Hunter, it has inhuman aggression too, but instead of abnormal leaping distance, the Charger instead charge with his right hand striking toward a group of survivor, stunning non-targets and catching the target to be pounded into submission.
*** The Jockey, a skeletal hunched man with the posture of a monkey and the ability to painfully grab a survivor moving the victim around.

* "Questionable Ethics" is set in a test chamber of sorts. However, unlike the clean and pristine looking of an [[Videogame/{{Portal}} Aperture Science Test Chamber]], the test chamber is instead straight out of ''Franchise/{{SAW}}'', though with less rust and stain. Though it doesn't make it less dangerous as players are to be expected fighting hordes and special infected in cramped areas, with some parts being downright claustrophobic.

** A part of the fourth chapter of "Vienna Calling 1" has you navigating a river ''with toxic waste that can drain your health''. Good luck playing this potion with bots.