History NightmareFuel / MassEffect1

* Fighting the Rachni on Noveria is scary enough by itself, but the tactics used to fight them make them even scarier. Since biotics such as "Throw" and Lift" are the only ways to effectively fight the Rachni without them trampling you, you're not just fighting poison-shooting spiders the size of tanks, you're fighting ''flying'' poison-shooting spiders the size of tanks.

** The [[GhostShip derelict freighter]] ''Cornucopia''. Your first clue something is wrong is when the Star Map description says that it's obviously adrift, but not broadcasting any distress signal. When you get on board, you find that it's been overrun by [[ArtificialZombie Husks]] who will rush you and try to overwhelm you in the claustrophobic crate maze of the cargo hold. Fighting your way to the cockpit, you discover the crew compartments are filled with [[ImpaledWithExtremePrejudice Dragon Teeths]]. The ship's main computer reveals that the crew encountered an alien artifact, and then made a mad dash to Geth Space, where they presumably were turned into husks and sent back into the galaxy proper as a warning or trap for organics.

* Oh God, the '''Rachni Song'''! It can be observed on various planets and moons, up to and including [[https://www.youtube.com/watch?v=NRmR0258vQ0 Luna]] where no Rachni could possibly exist! Creepy.

* The sidequest "I Remember Me", available to Colonist background players where Shepard must talk down a deranged former slave woman. To make it doubly so, the horrors Talitha describes? What she went through to drive her to the brink of suicide? Shepard was on the same colony the Batarians raided and about the only one to escape, and that's only because they were buried in rubble and left for dead after witnessing their parents [[ThereIsNoKillLikeOverkill get killed by an artillery strike]].

* Husks are the reanimated corpses of human beings with their nervous systems replaced with technology. The process is done by ''[[ImpaledWithExtremePrejudice impaling them on a spike]]''. In fact, ''they don't even have to be dead'' to be converted into Husks. The Geth (killer robots) don't ''look'' creepy (they have flashlights for heads), but the noise they make when they spot your squad ('''HRAAAAAAAAAAAAAAGH''') is horrific.

* The corpse puppet Asari commando jerking about like a marionette as the Rachni Queen talks through her.
** Speaking of the Rachni, there is also the part on Illium in VideoGame/MassEffect2 where you're greeted by an asari acting as a messenger for the Rachni Queen if you set her free back on Noveria.

* Also, Han Olar telling the story of how he escaped the Rachni. The scariest part is hearing how the Rachni in the labs are beyond saving. Essentially, the gist is that the Rachni are a telepathic sentient species. As long as the smaller ones are within telepathic range of the queen, they become intelligent and sentient. If they're outside the queen's range of influence, they go permanently feral. Just thinking about what that must be like, feeling your connection to the queen go, and then your mind following it, is chilling. Humans need contact with others to stay sane and so do the Rachni. Imagine a human child that has never had anyone hold it, comfort it or even ''talk to it.'' That's the Rachni you now face.

* The Hot Labs. Once you trigger the [[NeutronBomb neutron purge]], the main part of the chamber is instantly filled with Rachni. Dozens of them, and they don't stop. Your radar screen is ''full'' of red dots.

* Ilos. Think about it, and take the music out. A massive, abandoned city, overgrown with the vegetation of 50,000 years. Completely silent. The only thing you can here is the sound of your own squad's breathing, the sound of wind, and the electronic squawks and clanking of the Geth moving around the ruins. Then add horrific statues of Cthulhu that silently watch you, put in malfunctioning computers that scream "Can not be stopped! CAN NOT BE STOPPED!!!" at you and tell you about the creatures currently eating the brains of the now-dead inhabitants of the planet, and [[SerialEscalation THEN]] fill it with unspeaking, homicidal robots with plasma weapons who, once they've beaten you down, will stab you onto a ten-foot-tall pole and wait for your organs to dry out in order to turn you into a cyborg zombie.

--->'''Tali:''' We don't belong here. Not us, not Saren, not the Geth.
--->'''Ashley:''' Feels like something's watching us, and I don't mean the Geth... Let's just find the Conduit and get off this damn planet.

* Dr. Saleon's experiments. This was Garrus' ThatOneCase that severely traumatized him. To elaborate, Saleon grew artificial limbs and organs inside of his employees and surgically [[OrganTheft removed them]] when they were done growing. To make matters worse, if the organ wasn't good, [[BodyHorror he would just leave it inside]]. When C-SEC tried to apprehend him, he fled the Citadel with some employees. Garrus tried to have the Citadel's defense shoot him down, but they refused because of the hostages on-board. Garrus mentioned those hostages were [[FateWorseThanDeath good as dead]] anyway. What do you run into when you find him again? They are simply re-labeled Thorian Creepers. These are the end result of Saleon's medical experiments. These are one of only three "zombie" enemies you run into. The first are made with Reaper technology, the second by a 50,000+ year old sentient plant. These? Victims of a fucked-up Salarian organ thief. And when you find the man, there is absolutely ''no'' explanation given as to what he did or what reason he was doing it for. And there are well over a dozen of these victims. Is it any wonder Garrus is itching to rid the galaxy of this scumbag?

** In the same dialogue string where Garrus mentions Dr. Saleon, he also mentions an Elcor diplomat and SerialKiller on the Citadel who dismembered his victims.

* [[DepopulationBomb For every thousand Krogan women, one is capable of bearing children.]] Roll that one around in your head a bit. As of this writing, approximately 7 billion humans are alive, which would translate into only 3.5 million fertile women -- less than are currently living in New York City right now. The remaining billions of women wouldn't even know they're sterile until [[TragicStillbirth their children are stillborn.]] How long before even the barest pretenses of civilization collapse, with the handful of fertile women being little more than chattel for over half the world to fight over? Worse, the condition perpetuates even among the surviving children of fertile women -- how long before the population lacks enough genetic diversity to survive?
** It's worse than that. According to Mordin, the genophage is not a sterility plague, and all Krogan women can conceive children successfully. No, that one in a thousand statistic is the number of children who ''survive.'' The vast, vast majority of Krogan children are born dead - so, to have any chance at success, a Krogan mother must have hundreds, if not thousands of stillborn children in order to have ''one'' success.
** What makes the genophage even scarier? The fact that, according to Mordin and other salarians, even despite that horrific birthing rate, the Krogan would actually be having ''positive population growth'' if they weren't all rushing off to get killed as mercs and thugs. The Krogan breed so much that, even if only one in a thousand children survive, their population would still ''rise'' rather than decrease over time. Gives you some horrifying idea as to just how easily Krogan can strip a world bare, and why the other races decided that the genophage was their only option besides genocide. This is also why Mordin specifically mentions his work in modifying the genophage and releasing said modifications on Tuchanka, just to make sure that the Krogan weren't adapting to the original strain.
** After the release of the genophage and the de facto end of the Krogan rebellions, Urdnot Wrex wanted the clans to stop fighting and focus on breeding, if only for one generation (exactly what the Turians and Salarians intended the genophage to do to Krogan population). In response, Wrex's father tried to have Wrex and the Krogan loyal to him killed, during a truce at sacred grounds where violence is forbidden. Even when faced with extinction from warfare and irrecoverable losses, some Krogan wanted to ''keep fighting anyway''.
** It also puts into perspective just how much of a horrific DeathWorld Tuchanka is if ''this'' rate of reproduction was necessary to allow the Krogan to survive. [[spoiler:And Mass Effect 3 shows that Krogan aren't even at the top of Tuchanka's food chain. The top predators there are the Thresher Maws, including the [[{{Kaiju}} biggest Maw ever]], Kalros. Outside Tuchanka the Krogan are a deadly enemy, but in their planet's own ecosystem they're basically reduced to rabbits.]]
* Somewhere between actual nightmare fuel and fridge horror lies the situation that the scientists on Noveria find themselves in as the Rachni break free. Just imagine: you are in your lab, doing your everyday job, getting those last few tests done before you go on vacation. Then, out of the blue, alarms flare up, landlines (and thus communications) are disconnected, leaving you isolated in your lab. Then the power goes out, emergency generators kick in so lights and environmental controls work, but everything else is dead. No VI, no communications, no equipment, nothing. Then you hear those screeching and scurrying sounds coming from the pipes and ducts, screams and gunshots in the distance. You run for your life, trying to regroup when the co-worker you had breakfast with this morning gets cut in half by some alien creature from hell. If you happen to work in a different team, you will not even know what that thing is. So you regroup and wait for help. And you wait and wait, but nobody comes, and you know that if the situation is not controlled within a certain time frame, the managers back in Hanshan will order the place nuked from orbit. The screeching and crawling continues and every time a security team goes to deal with the situation, they come back with fewer people. Hours pass, nobody sleeps. You know the guards are overworked and on stims and then you see their fingers twitching...
** [[RussianGuySuffersMost Yaroslav Tartarovsky]], he's been stranded in the Hot Labs and was unable to flee due to the Rachni causing a lockdown of elevators. He'll give you some exposition on the Rachni, how Binary Helix found an egg in cryo on a derelict ship, that there's a [[NeutronBomb neutron purge]] that could wipe out the loose Rachni, etc... [[JumpScare Then out of nowhere]] a Rachni sneaks up on him and '''[[ImpaledWithExtremePrejudice impales]]''' him through the chest with one of its tentacles. That's not all. The poor bastard is still alive for a few seconds and gazes down in horror at the tentacle piercing his chest, before the Rachni just tosses him across the room violently like it was nothing.

* [[SandWorm Thresher Maws]]. These particular crawling nightmares suddenly sprout out from the ground, are about as high as a two storied building, and attack with a combination of acid spit and infrasound. These worms are the apex predators on the Krogan homeworld and even the Krogan fear them. And they spread via spores. So you could be a colonist just going about your daily life farming, tilling the soil, mining, building, hunting or foraging, and unbeknownst to you, a thresher maw is growing underneath you - conceived by spores that landed there probably a millennium ago. You remain blissfully unaware of it growing - and growing - until one day the earth shakes and it bursts forth to feed. They're not just [[NonMaliciousMonster incredibly dangerous animals]], they're [[TimeAbyss incredibly old]] animals that are [[CosmicHorrorStory virtually impossible to ever truly get rid off]].

* Shepard's [[https://www.youtube.com/watch?v=As0F9Bq2kGk nightmarish visions]] of the Prothean war with the Reapers, which mainly consists of the Protheans getting torn limb from limb by evil cyborgs or [[UnwillingRoboticisation forcibly fused with machinery]]. Further consider this: What you are actually watching in those visions is not the destruction of the Protheans per se, but their conversion into the Collectors. There's one side mission in which out of the blue you stumble across another Prothean artifact, which gives you the vision you know inside and out: except this time you are hit with the horrible realisation that one of the figure who is vainly trying to flee has four horizontally arranged eyes which are instantly recognisable. Believe it or not, there is a [[FateWorseThanDeath fate worse than extinction]]. And you're not just watching the Protheans' conversion, either. [[NothingIsScarier You don't even see all that much]], but whatever you see is enough to know it's not pretty. [[BodyHorror And you hear mechanical sawing noises]]. And screaming. [[HellIsThatNoise Lots of screaming]].

* It's bad enough when soldiers and police abuse their power and hide behind their respective agencies to avoid justice. But just imagine a rogue Spectre like Saren. Spectres can break almost any law to complete their mission. A good Spectre does his best to minimize collateral damage and innocent deaths, Saren not so much. If he doesn't like you, he will kill you and you don't even get the satisfaction of knowing that he will get in trouble, at least until Shepherd kicked his ass. Reading ''Literature/MassEffectRevelation'' will add to your nightmares as you understand just how much of a dick Saren was in making sure that Anderson wouldn't get a chance to become a Spectre.

** To makes matter worse, this was taken from Illos where the Prothean scientist was desperate trying to find out what the race before them was trying to learn what happened to them and that the vision they saw was in fact a second hand memory. As we learned the physiology of the actual Protheans themselves.

** The [[GhostShip derelict freighter]] ''Cornucopia''. Your first clue something is wrong is when the Star Map description says that it's obviously adrift, but not broadcasting any distress signal. When you get on board, you find that it's been overrun by [[ArtificialZombie Husks]] who will rush you and try to overwhelm you in the claustrophobic crate maze of the cargo hold. Fighting your way to the cockpit, you discover the crew compartments are filled with [[ImpaledWithExtremePrejudice Dragon Teeths]]. The ship's main computer reveals that the crew encountered an alien artefact, and then made a mad dash to Geth Space, where they presumably were turned into husks and sent back into the galaxy proper as a warning or trap for organics.

* Fighting the rachni on Noveria is scary enough by itself, but the tactics used to fight them make them even scarier. Since biotics such as "Throw" and Lift" are the only ways to effectively fight the rachni without them trampling you, you're not just fighting poison-shooting spiders the size of tanks, you're fighting ''flying'' poison-shooting spiders the size of tanks.

* Oh God, the '''Rachni Song'''! It can be observed on various planets and moons, up to and including [[https://www.youtube.com/watch?v=NRmR0258vQ0 Luna]] where no rachni could possibly exist! Creepy.
* The appearance of the Protheans themselves, in both visions and their statuary on Ilos, shows that they have ''tentacles'' coming from where you would expect eyes, and a head spookily reminiscent of Cthulu.

* The sidequest "I Remember Me", available to Colonist background players where Shepard must talk down a deranged former slave woman. To make it doubly so, the horrors Talitha describes? What she went through to drive her to the brink of suicide? Shepard was on the same colony the batarians raided and about the only one to escape, and that's only because they were buried in rubble and left for dead after witnessing their parents [[ThereIsNoKillLikeOverkill get killed by an artillery strike]].

* Husks are the reanimated corpses of human beings with their nervous systems replaced with technology. The process is done by ''[[ImpaledWithExtremePrejudice impaling them on a spike]]''. In fact, ''they don't even have to be dead'' to be converted into Husks. The geth (killer robots) don't ''look'' creepy (they have flashlights for heads), but the noise they make when they spot your squad ('''HRAAAAAAAAAAAAAAGH''') is horrific.

* The corpse puppet asari commando jerking about like a marionette as the Rachni Queen talks through her.
** Speaking of the rachni, there is also the part on Illium in VideoGame/MassEffect2 where you're greeted by an asari acting as a messenger for the Rachni Queen if you set her free back on Noveria.
* On Noveria, Matriarch Benezia's dying words. To make it more nightmarish: after being significantly weakened in attempting to stop Shepard and their squad, she manages to break free of indoctrination long enough to explain Saren's plans involving the rachni queen, and, if Liara is with Shepard, to say her final goodbyes to her daughter. Beforehand, according to her, her true self was locked in a dark corner of her mind as Saren imposed his will upon her through Sovereign. And she just manages to overcome the indoctrination just so that she could die as herself. And then the very last comforting thought she clung to as her life slipped away turned out to be nothing but an empty void.

* Also, Han Olar telling the story of how he escaped the rachni. The scariest part is hearing how the rachni in the labs are beyond saving. Essentially, the gist is that the rachni are a telepathic sentient species. As long as the smaller ones are within telepathic range of the queen, they become intelligent and sentient. If they're outside the queen's range of influence, they go permanently feral. Just thinking about what that must be like, feeling your connection to the queen go, and then your mind following it, is chilling. Humans need contact with others to stay sane and so do the rachni. Imagine a human child that has never had anyone hold it, comfort it or even ''talk to it.'' That's the rachni you now face.

* The Hot Labs. Once you trigger the [[NeutronBomb neutron purge]], the main part of the chamber is instantly filled with rachni. Dozens of them, and they don't stop. Your radar screen is ''full'' of red dots.

* Ilos. Think about it, and take the music out. A massive, abandoned city, overgrown with the vegetation of 50,000 years. Completely silent. The only thing you can here is the sound of your own squad's breathing, the sound of wind, and the electronic squawks and clanking of the geth moving around the ruins. Then add horrific statues of Cthulhu that silently watch you, put in malfunctioning computers that scream "Can not be stopped! CAN NOT BE STOPPED!!!" at you and tell you about the creatures currently eating the brains of the now-dead inhabitants of the planet, and [[SerialEscalation THEN]] fill it with unspeaking, homicidal robots with plasma weapons who, once they've beaten you down, will stab you onto a ten-foot-tall pole and wait for your organs to dry out in order to turn you into a cyborg zombie.

--->'''Tali:''' We don't belong here. Not us, not Saren, not the geth.
--->'''Ashley:''' Feels like something's watching us, and I don't mean the geth... Let's just find the Conduit and get off this damn planet.

* Dr. Saleon's experiments. This was Garrus' ThatOneCase that severely traumatized him. To elaborate, Saleon grew artificial limbs and organs inside of his employees and surgically [[OrganTheft removed them]] when they were done growing. To make matters worse, if the organ wasn't good, [[BodyHorror he would just leave it inside]]. When C-SEC tried to apprehend him, he fled the Citadel with some employees. Garrus tried to have the Citadel's defense shoot him down, but they refused because of the hostages on-board. Garrus mentioned those hostages were [[FateWorseThanDeath good as dead]] anyway. What do you run into when you find him again? They are simply re-labled Thorian Creepers. These are the end result of Saleon's medical experiments. These are one of only three "zombie" enemies you run into. The first are made with Reaper technology, the second by a 50,000+ year old sentient plant. These? Victims of a fucked-up salarian organ thief. And when you find the man, there is absolutely ''no'' explanation given as to what he did or what reason he was doing it for. And there are well over a dozen of these victims. Is it any wonder Garrus is itching to rid the galaxy of this scumbag?

* [[DepopulationBomb For every thousand krogan women, one is capable of bearing children.]] Roll that one around in your head a bit. As of this writing, approximately 7 billion humans are alive, which would translate into only 3.5 million fertile women -- less than are currently living in New York City right now. The remaining billions of women wouldn't even know they're sterile until [[TragicStillbirth their children are stillborn.]] How long before even the barest pretenses of civilization collapse, with the handful of fertile women being little more than chattel for over half the world to fight over? Worse, the condition perpetuates even among the surviving children of fertile women -- how long before the population lacks enough genetic diversity to survive?
** It's worse than that. According to Mordin, the genophage is not a sterility plague, and all krogan women can conceive children successfully. No, that one in a thousand statistic is the number of children who ''survive.'' The vast, vast majority of krogan children are born dead - so, to have any chance at success, a krogan mother must have hundreds, if not thousands of stillborn children in order to have ''one'' success.
** What makes the genophage even scarier? The fact that, according to Mordin and other salarians, even despite that horrific birthing rate, the krogan would actually be having ''positive population growth'' if they weren't all rushing off to get killed as mercs and thugs. The krogan breed so much that, even if only one in a thousand children survive, their population would still ''rise'' rather than decrease over time. Gives you some horrifying idea as to just how easily krogan can strip a world bare, and why the other races decided that the genophage was their only option besides genocide. This is also why Mordin specifically mentions his work in modifying the genophage and releasing said modifications on Tuchanka, just to make sure that the krogan weren't adapting to the original strain.

** It also puts into perspective just how much of a horrific DeathWorld Tuchanka is if ''this'' rate of reproduction was necessary to allow the Krogan to survive. [[spoiler:And Mass Effect 3 shows that Krogan aren't even at the top of Tuchanka's food chain. The top predators there are the Thresher Maws, including the [[{{Kaiju}} biggest Maw ever]], Kalros. Outside Tuchanka the krogan are a deadly enemy, but in their planet's own ecosystem they're basically reduced to rabbits.]]

* [[SandWorm Thresher Maws]]. These particular crawling nightmares suddenly sprout out from the ground, are about as high as a two storied building, and attack with a combination of acid spit and infrasound. These worms are the apex predators on the krogan homeworld and even the krogan fear them. And they spread via spores. So you could be a colonist just going about your daily life farming, tilling the soil, mining, building, hunting or foraging, and unbeknownst to you, a thresher maw is growing underneath you - conceived by spores that landed there probably a millennium ago. You remain blissfully unaware of it growing - and growing - until one day the earth shakes and it bursts forth to feed. They're not just [[NonMaliciousMonster incredibly dangerous animals]], they're [[TimeAbyss incredibly old]] animals that are [[CosmicHorrorStory virtually impossible to ever truly get rid off]].

** ''MSV Worthington''. A drifting, abandoned ship in space housing a brain-dead man by the name of Jacob, on life support systems. Turns out the crew planned on pulling the plug - the only problem being that it did not go that well with Jacob's [[TheForce biotic]], PTSD girlfriend. The part where upon hearing the last entry in the Captain's log, which ends in his bloodcurdling scream, Julia suddenly appears and rabidly attacks you made it even more disturbing. And you can search every corner of the entire ship prior to hearing the logs and find nothing, not even a trace of where Julia might be. This means that she must've been hiding very well, [[ParanoiaFuel watching your every move the moment you entered the ship]], and trying to anticipate how much of a threat you were to Jacob before madly rushing in and attempting to kill you.

* On Noveria, Matriarch Benezia's dying words. To make it more nightmarish: after being significantly weakened in attempting to stop Shepard and his squad, she manages to break free of indoctrination long enough to explain Saren's plans involving the rachni queen, and, if Liara is with Shepard, to say her final goodbyes to her daughter. Beforehand, according to her, her true self was locked in a dark corner of her mind as Saren imposed his will upon her through Sovereign. And she just manages to overcome the indoctrination just so that she could die as herself. And then the very last comforting thought she clung to as her life slipped away turned out to be nothing but an empty void.

** Some of these bullet mods are explicitly mentioned to be made of Polonium, or covered in toxic chemicals, and they're a favorite of criminals. Something that would be a clear violation of UsefulNotes/TheLawsAndCustomsOfWar in real life is apparently normal in the Mass Effect galaxy, and you can use these mods with no consequences.

** It also puts into perspective just how much of a horrific DeathWorld Tuchanka is if ''this'' rate of reproduction was necessary to allow the Krogan to survive.

*** Your party members even mention once you set off the first bomb that it feels like someone's watching you.

* [[DepopulationBomb For every thousand krogan women, one is capable of bearing children.]] Roll that one around in your head a bit. As of this writing, approximately 7 billion humans are alive, which would translate into only 3.5 million fertile women -- less than are currently living in New York City right now. The remaining billions of women wouldn't even know they're sterile until [[AdultFear their children are stillborn.]] How long before even the barest pretenses of civilization collapse, with the handful of fertile women being little more than chattel for over half the world to fight over? Worse, the condition perpetuates even among the surviving children of fertile women -- how long before the population lacks enough genetic diversity to survive?

** [[RussianGuySuffersMost Yaroslav Tartarovsky]], he's been stranded in the Hot Labs and was unable to flee due to the Rachni causing a lockdown of elevators. He'll give you some exposition on the Rachni, how Binary Helix found an egg in cryo on a derelict ship, that there's a [[NeutronBomb neutron purge]] that could wipe out the loose Rachni, etc... [[JumpScare Then out of nowhere]] a Rachni sneaks up on him and '''[[ImpaledWithExtremePrejudice impales]]''' him through the chest with one of its tentacles. That's not all. The poor bastard is still alive for a few seconds and gaze down in horror and the tentacle piercing his chest, before the Rachni just tosses him across the room violently.

* ''MSV Worthington''. A drifting, abandoned ship in space housing a brain-dead man by the name of Jacob, on life support systems. Turns out the crew planned on pulling the plug - the only problem being that it did not go that well with Jacob's [[TheForce biotic]], PTSD girlfriend. The part where upon hearing the last entry in the Captain's log, which ends in his bloodcurdling scream, Julia suddenly appears and rabidly attacks you made it even more disturbing. And you can search every corner of the entire ship prior to hearing the logs and find nothing, not even a trace of where Julia might be. This means that she must've been hiding very well, [[ParanoiaFuel watching your every move the moment you entered the ship]], and trying to anticipate how much of a threat you were to Jacob before madly rushing in and attempting to kill you.
** Your party members even mention once you set off the first bomb that it feels like someone's watching you.
** Audio logs claim that Julia's insanity is at least partly due to her biotic implant. It's not stated what configuration she uses, but the mention that her stress-induced implant flareups are causing intense migraines indicates that she's an L2. There's a reason Kaidan repeatedly states that he's one of the lucky [=L2s=].

* Shepard's [[https://www.youtube.com/watch?v=As0F9Bq2kGk nightmarish visions]] of the Prothean war with the Reapers, which mainly consists of the Protheans getting torn limb from limb by evil cyborgs. Further consider this: What you are actually watching in those visions is not the destruction of the Protheans per se, but their conversion into the Collectors. There's one side mission in which out of the blue you stumble across another Prothean artifact, which gives you the vision you know inside and out: except this time you are hit with the horrible realisation that one of the figure who is vainly trying to flee has four horizontally arranged eyes which are instantly recognisable. Believe it or not, there is a fate worse than extinction. And you're not just watching the Protheans' conversion, either. [[NothingIsScarier You don't even see all that much, but whatever you see is enough to know it's not pretty]]. [[BodyHorror And you hear mechanical sawing noises.]] [[FateWorseThanDeath And screaming]]. [[HellIsThatNoise Lots of screaming]].

-->"No light? They said there would be a... ah..."

* Ammo that goes under the category of 'fire', 'ice', or 'poison' in the game will ''disintegrate'' enemies upon killing them. and it ''can'' happen to you.

* The Hot Labs. Once you trigger the neuron purge, the main part of the chamber is instantly filled with rachni. Dozens of them, and they don't stop. Your radar screen is ''full'' of red dots.

* The [[GhostShip derelict freighter]] ''Cornucopia''. You're slowly making your way through the labyrinthine cargo hold and then a herd of husks suddenly attacks you.

* Dr. Saleon's experiments. To elaborate he grew artificial limbs and organs inside of his employees and surgically removed them when they were done growing. To make matters worse, if the organ wasn't good, he would just leave it inside. Not to mention what you run into when you find him again. They are simply re-labled Thorian Creepers. These are the end result of Saleon's medical experiments. These are one of only three "zombie" enemies you run into. The first are made with Reaper technology, the second by a 50,000+ year old sentient plant. These? Victims of a fucked-up salarian organ thief. And when you find the man, there is absolutely ''no'' explanation given as to what he did or what reason he was doing it for. And there are well over a dozen of these victims. Is it any wonder Garrus is itching to rid the galaxy of this scumbag?

* Husks are the reanimated corpses of human beings with their nervous systems replaced with technology. The process is done by ''[[ImpaledWithExtremePrejudice impaling them on a spike]]''. In fact, ''they don't even have to be dead'' to be converted into Husks. The geth (killer robots) don't ''look'' creepy (they have flashlights for heads), but the noise they make when they spot your squad ('''HRAAAAAAAAAAAAAAGH''') is horrific. And then there's Shepard's nightmarish visions of the Prothean war with the Reapers, which mainly consists of the Protheans getting torn limb from limb by evil cyborgs. Further consider this: What you are actually watching in those visions is not the destruction of the Protheans per se, but their conversion into the Collectors. There's one side mission in which out of the blue you stumble across another Prothean artifact, which gives you the vision you know inside and out: except this time you are hit with the horrible realisation that one of the figure who is vainly trying to flee has four horizontally arranged eyes which are instantly recognisable. Believe it or not, there is a fate worse than extinction. And you're not just watching the Protheans' conversion, either. [[NothingIsScarier You don't even see all that much, but whatever you see is enough to know it's not pretty]]. [[BodyHorror And you hear mechanical sawing noises.]] [[FateWorseThanDeath And screaming]]. [[HellIsThatNoise Lots of screaming.]]

* Species 37. The Thorian is a sentient plant that controls minds through Pavlovian MindRape. Then you find out that it produces hideous zombie-like humanoids called [[http://masseffect.wikia.com/wiki/Thorian_Creeper Thorian Creepers]], and promptly lose your lunch. The horror might be somewhat alleviated by the fact that the [[OneGenderRace asari clones]] it spits out are somehow [[GreenSkinnedSpaceBabe still quite lithe]], but [[FridgeLogic then you realize that]] the fact that this thing can spit out powerful [[MindOverMatter biotics]] at will might not be a good thing.

** Speaking of MindRape, that mind control! The Thorian causes debilitating pain at even the ''thought'' of resistance. Ian Newstead tries to drop hints and seems to take a perverse joy in "invoking the master's whip", but even he can't do anything. If you save the colonists one describes the control as making any pure thought into agony. Another says it was like being slapped every time she started to raise her eyes.
** And this is something that the company funding the colony just ''let happen'' so they could study it!

* [[SandWorm Thresher Maws]]. These particular crawling nightmares suddenly sprout out from the ground, are about as high as a two storied building, and attack with a combination of acid spit and infrasound. These worms are the apex predators on the krogan homeworld and even the krogan fear them. And they spread via spores. So you could be a colonist just going about your daily life f farming, tilling the soil, mining, building, hunting or foraging, and unbeknownst to you, a thresher maw is growing underneath you - conceived by spores that landed there probably a millennium ago. You remain blissfully unaware of it growing - and growing - until one day the earth shakes and it bursts forth to feed.

-->'''Sovereign''': '''[[AC:Your words are as empty as your future. I am the vanguard of your destruction. This exchange is over.]]'''

** The literal swarms of Thorian Creepers crouched fetal position on the floor, just ''waiting'' for you to walk closer, before jumping up, '''skipping''' at you, and then just standing in front of you for a moment, swaying slightly, then ''vomiting acid all over you''. The fact that they look like [=ReDeads=] don't help at all. Remember too that they don't all get up when you get close: they're invulnerable while they're inert, but you could be fending off a wave that's swarming from the next room only to realize that you're surrounded by inert creepers...and they're waking up.

* ''MSV Worthington''. A drifting, abandoned ship in space housing a brain-dead man by the name of Jacob, on life support systems. Turns out the crew planned on pulling the plug - the only problem being that it did not go that well with Jacob's [[TheForce biotic]], PTSD girlfriend. The part where upon hearing the last entry in the Captain's log, which ended in his bloodcurdling scream, Julia suddenly appears and rabidly attacks you made it even more disturbing. And you can search every corner of the entire ship prior to hearing the logs and find nothing, not even a trace of where Julia might be. This means that she must've been hiding very well, [[ParanoiaFuel watching your every move the moment you entered the ship]], and trying to anticipate how much of a threat you were to Jacob before madly rushing in and attempting to kill you.

* [[SandWorm Thresher Maws]]. These particular crawling nightmares suddenly sprout out from the ground, are about as high as a two storied building, and attack with a combination of acid spit and infrasound. These worms are the apex predators on the Krogan homeworld and even the Krogan fear them. And they spread via spores. So you could be a colonist just going about your daily life f farming, tilling the soil, mining, building, hunting or foraging, and unbeknownst to you, a thresher maw is growing underneath you - conceived by spores that landed there probably a millennium ago. You remain blissfully unaware of it growing - and growing - until one day the earth shakes and it bursts forth to feed.

** There were [[WildMassGuessing theories]] that this was the genesis of the [[MechanicalAbomination Reapers]], but this was {{Jossed}} by the time of ''VideoGame/MassEffect3''. Still, ''[[NothingIsScarier what the hell happened there]]''?

* [[SandWorm Thresher Maws]]. These particular crawling nightmares suddenly sprout out from the ground, are about as high as a two storied building, and attack with a combination of acid spit and infrasound. These worms are the apex predators on the Krogan homeworld and even the Krogan fear them. And they spread via spores. So you could be a colonist just going about your daily life f farming, tilling the soil, mining, building, hunting or foraging, and unbeknownst to you, a thresher maw is growing underneath you - conceived by spores that landed there probably a millennium ago. You remain blissfully unaware of it growing - and growing - until one day the earth shakes and it bursts forth to feed.

* It's bad enough when soldiers and police abuse their power and hide behind their respective agencies to avoid justice. But just imagine a rogue Spectre like Saren. Spectres can break almost any law to complete their mission. A good Spectre does his best to minimize collateral damage and innocent deaths, Saren not so much. If he doesn't like you, he will kill you and you don't even get the satisfaction of knowing that he will get in trouble, at least until Shepherd kicked his ass. Reading ''Literature/MassEffectRevelation'' will add to your nightmares as you understand just how much of a dick Saren was in making sure that Anderson wouldn't get a chance to become a Spectre.

* Fighting the rachni on Noveria is scary enough by itself, but the tactics used to fight them makes them even scarier. Since biotics such as "Throw" and Lift" are the only ways to effectively fight the rachni without them trampling you, you're not just fighting poison-shooting spiders the size of tanks, you're fighting ''flying'' poison-shooting spiders the size of tanks.

* ''MSV Worthington''. A [[spoiler:drifting, abandoned ship in space housing a brain-dead man by the name of Jacob, on life support systems. Turns out the crew planned on pulling the plug - the only problem being that it did not go that well with Jacob's [[TheForce biotic]], PTSD girlfriend.]] The part where [[spoiler:upon hearing the last entry in the Captain's log, which ended in his bloodcurdling scream, Julia suddenly appears and rabidly attacks you]] made it even more disturbing. And you can search every corner of the entire ship prior to hearing the logs and find nothing, not even a trace of where Julia might be. This means that she must've been hiding very well, [[ParanoiaFuel watching your every move the moment you entered the ship]], and trying to anticipate how much of a threat you were to Jacob before madly rushing in and attempting to kill you.
* The [[spoiler:VI on Luna instantly putting up barriers in all doorways after trashing the second processor cluster.]] Even more creepy: The binary code it sends just before it dies? It means "HELP!". ''VideoGame/MassEffect2'' reveals that [[spoiler: the VI was actually a sentient Artificial Intelligence. So, you basically killed a sapient being that was just trying to defend itself once the Alliance realised it had become self-aware. Humanity [[HistoryRepeats started their very own Morning War in miniature]] and you, ''personally,'' had a hand in it.]] What's more, in-game information you discover makes you realize that [[spoiler: Cerberus, those goons you're working for, were responsible for hacking the VI and giving it sentience]]. VideoGame/MassEffect3 reveals that [[spoiler: EDI used to be that AI, ''and'' she remembers what happened. Good thing she doesn't hold a grudge.]]
* Oh God, the [[spoiler:'''Rachni Song''']]! It can be observed on various planets and moons, up to and including [[https://www.youtube.com/watch?v=NRmR0258vQ0 Luna]] where no [[spoiler:rachni could possibly exist]]! Creepy.

** [[spoiler:Those aren't actually the Protheans- Javik reveals in [=ME3=] that they are an extinct race called the Inusannon who came before the Protheans. Still doesn't make them less horrifying, though.]]
* The scene before the final fight with [[spoiler: Saren twitching in the air, screaming as his flesh sloughs off, revealing the metallic skeleton beneath.]] BodyHorror at its finest.

** If you had enough Charm or Intimidate points, you get to see Saren [[spoiler:blow his own brains out. As in, you can watch the side of his head explode as he pulls the trigger]].
* The sidequest "I Remember Me", available to Colonist background players [[spoiler:where Shepard must talk down a deranged former slave woman.]] To make it doubly so, the horrors Talitha describes? What she went through to drive her to the brink of suicide? Shepard was on the same colony the batarians raided and about the only one to escape, and that's only because they were buried in rubble and left for dead after witnessing their parents [[ThereIsNoKillLikeOverkill get killed by an artillery strike]].

* When [[spoiler:[[EldritchAbomination Sovereign]]]] reveals itself. Even better if you'd managed to not spoil yourself before then. The music, [[EvilSoundsDeep the voice]], and the slowly building sensation of dread you feel as you realise just what it is you're up against.
-->'''[[spoiler:Sovereign]]''': [[spoiler:'''[[AC:Your words are as empty as your future. I am the vanguard of your destruction. This exchange is over.]]''']]
* Husks are the reanimated corpses of human beings with their nervous systems replaced with technology. The process is done by ''[[ImpaledWithExtremePrejudice impaling them on a spike]]''. In fact, ''they don't even have to be dead'' to be converted into Husks. The geth (killer robots) don't ''look'' creepy (they have flashlights for heads), but the noise they make when they spot your squad ('''HRAAAAAAAAAAAAAAGH''') is horrific. And then there's Shepard's nightmarish visions of [[spoiler:the Prothean war with the Reapers, which mainly consists of the Protheans getting torn limb from limb by evil cyborgs]]. Further consider this: [[spoiler:What you are actually watching in those visions is not the destruction of the Protheans per se, but their conversion into the Collectors. There's one side mission in which out of the blue you stumble across another Prothean artifact, which gives you the vision you know inside and out: except this time you are hit with the horrible realisation that one of the figure who is vainly trying to flee has four horizontally arranged eyes which are instantly recognisable. Believe it or not, there is a fate worse than extinction.]] And you're not just watching [[spoiler:the Protheans' conversion, either. [[NothingIsScarier You don't even see all that much, but whatever you see is enough to know it's not pretty]]. [[BodyHorror And you hear mechanical sawing noises.]] [[FateWorseThanDeath And screaming]]. [[HellIsThatNoise Lots of screaming.]]]]
* Imagine it. You're peacefully going about your business in the wards of the Citadel when suddenly sirens begin to wail. Completely out of nowhere, unknown, gargantuan starships of unfathomable power emerge and exterminate everything, spreading out across your empire and slaughtering, subjugating or [[spoiler:genetically modifying]] everything you hold dear, then using [[spoiler:the liquefied slurry that used to be your bodies to produce and power more of themselves.]] This is the fate of the Protheans, and innumerable species before them. And it's going to happen again, and again, and again... Seriously, the Reapers themselves are the scariest thing in the game. Made even worse by several of [[spoiler:Harbinger]]'s lines in ''Mass Effect 2'': [[spoiler:"Sentient beings need never fear me." "We are your salvation through destruction." The Reapers believe that they are doing these species a FAVOR.]] The ending of the first Prothean message on Ilos springs to mind. [[spoiler:'''''"Cannot be stopped... cannot be STOPPED..."''''']] And turned into diesel was the ''lucky'' fate for most of them. The rest [[spoiler: were forcibly mutated into the Collectors.]]
* [[spoiler: The corpse puppet asari commando jerking about like a marionette as the Rachni Queen talks through her.]]
** Speaking of [[spoiler:the rachni]], there is also the part on Illium in VideoGame/MassEffect2 where [[spoiler:you're greeted by an asari acting as a messenger for the Rachni Queen if you set her free back on Noveria.]]
* On Noveria, [[spoiler:Matriarch Benezia's dying words]]. To make it more nightmarish: [[spoiler:after being significantly weakened in attempting to stop Shepard and his squad, she manages to break free of indoctrination long enough to explain Saren's plans involving the rachni queen, and, if Liara is with Shepard, to say her final goodbyes to her daughter. Beforehand, according to her, her true self was locked in a dark corner of her mind as Saren imposed his will upon her through Sovereign. And she just manages to overcome the indoctrination just so that she could die as herself. And then the very last comforting thought she clung to as her life slipped away turned out to be nothing but an empty void]].

* Species 37. The Thorian is a [[spoiler: sentient plant that controls minds through Pavlovian MindRape]]. Then you find out that [[spoiler:it produces hideous zombie-like humanoids called]] [[http://masseffect.wikia.com/wiki/Thorian_Creeper Thorian Creepers]], and promptly lose your lunch. The horror might be somewhat alleviated by the fact that [[spoiler:the [[OneGenderRace asari clones]] it spits out are somehow [[GreenSkinnedSpaceBabe still quite lithe]],]] but [[FridgeLogic then you realize that]] [[spoiler:the fact that this thing can spit out powerful [[MindOverMatter biotics]] at will]] might not be a good thing.

** Speaking of [[spoiler: MindRape, that mind control!]] The Thorian causes debilitating pain [[spoiler: at even the ''thought'' of resistance. Ian Newstead tries to drop hints and seems to take a perverse joy in "invoking the master's whip", but even he can't do anything. If you save the colonists one describes the control as making any pure thought into agony. Another says it was like being slapped every time she started to raise her eyes.]]

* Also, Han Olar telling the story of [[spoiler:how he escaped the rachni.]] The scariest part is hearing how the rachni in the labs are beyond saving. Essentially, the gist is that [[spoiler:the rachni are a telepathic sentient species. As long as the smaller ones are within telepathic range of the queen, they become intelligent and sentient. If they're outside the queen's range of influence, they go permanently feral. Just thinking about what that must be like, feeling your connection to the queen go, and then your mind following it, is chilling.]] Humans need contact with others to stay sane [[spoiler:and so do the rachni. Imagine a human child that has never had anyone hold it, comfort it or even ''talk to it.'' That's the rachni you now face.]]
-->[[spoiler: '''Rachni Queen:''' Fear has shattered their minds.]]

* The Hot Labs. [[spoiler: Once you trigger the neuron purge, the main part of the chamber is instantly filled with rachni. Dozens of them, and they don't stop. Your radar screen is ''full'' of red dots.]]
* It gets worse in a similar side mission in ''Mass Effect 2''. [[spoiler:While you're out scanning planets for minerals or side missions, you receive an anomalous distress beacon. EDI tells you there's signs of movement, but no organic life, so you assume either rogue robots or geth, so you create your team appropriately to deal with that. WRONG. The landing cinematic shows a "Blink and You'll Miss It" moment of a husk wandering past the entrance, ignoring you. You decide to go back to the Normandy to reform your team appropriately, but the auto-nav makes it fly away, giving you no choice but to press onwards. Once inside, you find a Franchise/ResidentEvil style file telling you to get the hell out of there, ASAP. That's when the fun begins. Heading deeper into the mines, you find more Husks than the first Mass Effect ever had, and their [[IncendiaryExponent exploding cousins the Abominations]]. Deeper in, you find more files telling of the miners' fates, along with some Husks dropping down from the ceiling, before going through one more mass of Husks to destroy the mines and complete the mission. ]]
* The [[GhostShip derelict freighter]] ''Cornucopia''. You're slowly making your way through the labyrinthine cargo hold and then [[spoiler: a herd of husks suddenly attacks you.]]
* Indoctrination is the worst thing to happen to anyone. Let's take a situation like Benezia's example, assuming the Reaper has an organic commander like Saren. You initially despise him, can't believe you have to put up with him. And as time goes on, you start agreeing with his commands. You sit at his feet, and smile and nod, while he details all his plans of torture and galactic annihilation. Now, imagine after a while, you are now in a glass box hovering above the world, your arms bound but you are still able to move. It hovers over a man or a woman who looks just like you, as they walk through a town, slaughtering innocents. Men, women, children, he kills all of them because the man in the angry mechanical cuttlefish says to. And you try so desperately to stop it, to break the glass by throwing yourself into it, but not even a crack appears. You just keep making yourself weaker, the wo/man quickens their step. And then, when you've finally exhausted yourself, they stop, and stand. Just stands, and does nothing else. Maybe mumbles some nonsense. And you lie there, bruised and broken, sobbing until the wo/man dies, and you're finally released. ''That'' is the true definition of Hell. Worse if you consider that, if you aren't like Benezia, you will feel your mind crumbling bit by bit, until you're just a zombie. Imagine every memory, dream, feeling and desire, being slowly erased, while you're unable to do anything except waiting for your mind to be consumed by the void, leaving [[FateWorseThanDeath no]][[AndIMustScream thing]]... Remember that hanging around a Reaper is not the only way to get indoctrinated: [[spoiler:Shepard's "paperweight"]] can do it as well.

** The countless cryo pods... [[spoiler: all of them filled with 50,000 year-old-corpses.]]

* Dr. Saleon's experiments. To elaborate he [[spoiler: grew artificial limbs and organs inside of his employees and surgically removed them when they were done growing. To make matters worse, if the organ wasn't good, he would just leave it inside]]. Not to mention [[spoiler: what you run into when you find him again. They are simply re-labled Thorian Creepers. These are the end result of Saleon's medical experiments. These are one of only three "zombie" enemies you run into. The first are made with Reaper technology, the second by a 50,000+ year old sentient plant. These? Victims of a fucked-up salarian organ thief. And when you find the man, there is absolutely ''no'' explanation given as to what he did or what reason he was doing it for. And there are well over a dozen of these victims]]. Is it any wonder Garrus is itching to rid the galaxy of this scumbag?
--> '''Garrus:''' [[spoiler:I'd harvest his organs]], but we don't have enough time.

* Somewhere between actual nightmare fuel and fridge horror lies the situation that the scientists on Noveria find themselves in as the [[spoiler:Rachni]] break free. Just imagine: you are in your lab, doing your everyday job, getting those last few tests done before you go on vacation. Then, out of the blue, alarms flare up, landlines (and thus communications) are disconnected, leaving you isolated in your lab. Then the power goes out, emergency generators kick in so lights and environmental controls work, but everything else is dead. No VI, no communications, no equipment, nothing. Then you hear those screeching and scurrying sounds coming from the pipes and ducts, screams and gunshots in the distance. You run for your life, trying to regroup when the co-worker you had breakfast with this morning gets cut in half by some alien creature from hell. If you happen to work in a different team, you will not even know what that thing is. So you regroup and wait for help. And you wait and wait, but nobody comes, and you know that if the situation is not controlled within a certain time frame, the managers back in Hanshan will order the place nuked from orbit. The screeching and crawling continues and every time a security team goes to deal with the situation, they come back with fewer people. Hours pass, nobody sleeps. You know the guards are overworked and on stims and then you see their fingers twitching...

* There is a track that was never released on the official soundtrack called "[[https://www.youtube.com/watch?v=37WL8SdFYE4 Abandoned Facility]]". It plays in the prefab bunkers on uncharted worlds and in some parts of Noveria's Peak 15 facility and it's creepy to no end, NothingIsScarier in music form.

* The sidequest "I Remember Me", available to Colonist background players [[spoiler:where Shepard must talk down a deranged former slave woman.]] To make it doubly so, the horrors Talitha describes? What she went through to drive her to the brink of suicide? Shepard was on the same colony the batarians raided and about the only one to escape, and that's only because s/he was buried in rubble and left for dead after witnessing her/his parents [[ThereIsNoKillLikeOverkill get killed by an artillery strike]].

** Add to this her line about how they "did things to her in the dark". Oh, and Shepard was sixteen when s/he was left for dead. Talitha (the young woman in question) was [[WouldHurtAChild SIX]]. What did Slavers do to a six year old girl? Keep in mind Mindoir is also the event that caused Spacer Shepard's side mission NPC [[ShellShockedVeteran Zabaleta]] to suffer PTSD and hit rock bottom.

* Indoctrination is the worst thing to happen to anyone. Let's take a situation like Benezia's example, assuming the Reaper has an organic commander like Saren. You initially despise him, can't believe you have to put up with him. And as time goes on, you start agreeing with his commands. You sit at his feet, and smile and nod, while he details all his plans of torture and galactic annihilation. Now, imagine after a while, you are now in a glass box hovering above the world, your arms bound but you are still able to move. It hovers over a man or a woman who looks just like you, as s/he walks through a town, slaughtering innocents. Men, women, children, he kills all of them because the man in the angry mechanical cuttlefish says to. And you try so desperately to stop it, to break the glass by throwing yourself into it, but not even a crack appears. You just keep making yourself weaker, the wo/man quickens their step. And then, when you've finally exhausted yourself, s/he stops, and stands. Just stands, and does nothing else. Maybe mumbles some nonsense. And you lie there, bruised and broken, sobbing until the wo/man dies, and you're finally released. ''That'' is the true definition of Hell. Worse if you consider that, if you aren't like Benezia, you will feel your mind crumbling bit by bit, until you're just a zombie. Imagine every memory, dream, feeling and desire, being slowly erased, while you're unable to do anything except waiting for your mind to be consumed by the void, leaving [[FateWorseThanDeath no]][[AndIMustScream thing]]... Remember that hanging around a Reaper is not the only way to get indoctrinated: [[spoiler:Shepard's "paperweight"]] can do it as well.