History YMMV / Undertale

* CommonKnowledge:
** 'Determination' is often cited with full confidence as the 'trait' for the red SOUL; however, in-game, the red SOUL's trait is never stated, and furthermore, it's mentioned several times over that ''all'' humans have Determination. Also, in-game, the only color Determination is assigned is yellow [[spoiler:in Alphys' True Labs entries]]; every other time it's mentioned, it gets plain white text, and it isn't listed with the other traits during the Ball Game, although, curiously enough, 'Ball Game' ''is'' written in red text should you beat it with every other color.
** The Human Child[[spoiler:/Frisk]] is often drawn wearing shorts due to the limited pixel art of the game, but a simple look on [[https://ksr-ugc.imgix.net/assets/011/533/904/f58978f175eba8065d1b5afe4545876d_original.png?ixlib=rb-4.0.2&crop=faces&w=1552&h=873&fit=crop&v=1463684109&auto=format&frame=1&q=92&s=e3cc8b22a13b5f5efcf34ad2793dac51 the official art]] shows that they're wearing pants [[spoiler:(the same applies for the Fallen Human/Chara)]]. However, this example is less true with time, considering [[https://pbs.twimg.com/media/EtueUT9XIAMu_I1.jpg more official art]] shows them wearing shorts.
** It's very common for fans to assert that [[spoiler:the Fallen Human/Chara deliberately jumped into the underground in a failed suicide attempt, especially as an arguing point for viewing them sympathetically]]. While Asriel does state that they climbed Mt. Ebott for, quote, [[spoiler:'not a happy reason', we clearly see in the intro that Chara accidentally fell into the hole leading underground by tripping on a root (and, no, Flowey's not responsible because he didn't exist yet)]].
** A tremendous amount of fanart exists out there depicting Sans with the ability to [[spoiler:[[RippleEffectProofMemory fully remember previous game sessions]], particularly ones where either his loved ones are killed or the happy ending is stolen away from him]], leading to many a great TearJerker. Because of this, it comes as a surprise to some to find that he in fact ''does not'' have this ability in the same way your character or Flowey does; if anything, [[spoiler:he only has the same vague, subconscious memories about them that every main character does and that's it. What sets Sans apart is the fact that he knows the previous timelines ''exist'', and uses this information to make [[HyperAwareness very specific (and uncannily accurate) guesses]] based on your body language and behavior as to what you've been doing in previous game sessions. Likely due to how specific (and frequently accurate) these guesses are, many people mistakenly got the impression that he actually has RippleEffectProofMemory like Flowey or the player, and it's difficult to discern the fans who genuinely believe it and those who just see it as a compelling "What if?" scenario. It's implied that he ''might'' have the ability to save physical objects from timelines that have been lost, judging by the contents of his secret room, but that's less definitive.]]
** Speaking of Sans, you'd be forgiven for thinking that when his eye glows, it only glows blue, given how often it's depicted as such in fanworks. In fact, anytime his eye glows, it always flashes blue and yellow. There are zero instances in the game where it is only blue (or only yellow).
*** Similarly, you'd be forgiven for thinking that the glow manifests as an emitted flame, when in-game it's depicted as [[GlowingEyesOfDoom a flashing pupil]] and the color never leaves the socket.
** Many people believe that buttercups and golden flowers are the same species. They can't actually be because, if they were, [[spoiler:Chara's fake request to see the golden flowers would have been easily fulfilled as buttercups already grew in the Underground as evidenced by them and Asriel putting them into a pie once. Alphys's True Lab entries state that the golden flower that would become Flowey was the first one to grow in the Underground and that it did so not long before Toriel left.]]
** A surprisingly common belief in gaming circles is that the game was made with MediaNotes/RPGMaker. It was actually made entirely in [[https://en.wikipedia.org/wiki/GameMaker_Studio Game Maker Studio]]. While it is true that RPG Maker has been purpose-built for creating the sort of Platform/{{SNES}}-era JRPG ''Undertale'' has clearly been InspiredBy, it doesn't handle real-time action well: though there are some ActionRPG games made with it like ''VideoGame/{{Avarice}}'' (or even a straight-up ShootEmUp like ''VideoGame/SkyE''), its turn-based battle interface is quite rigid, and interspersing it with the real-time dodging segments that became ''Undertale's'' calling card would have been too complicated to bother with.
** Many think that due to being soulless, Flowey doesn't feel ''anything''. In reality, however, a monster's SOUL is made out of love, compassion and empathy - And due to being soulless, Flowey can feel everything ''except'' those three things. He's actually shown to be scared, sad and even happy (although through sadistic means) throughout the game.
** On the musical front, a search of the game's music and its many, ''many'' covers might give you the impression that Asgore's battle theme is titled "Bergentrückung". It's not; "Bergentrückung" is the name of the song that plays ''before'' the battle, during the cutscene where [[spoiler:he destroys the MERCY button]]. His actual theme is just called "ASGORE".
** It's widely believed in the ''Undertale'' fandom that Papyrus hates puns to the point of them being his BerserkButton. The truth is that Papyrus ''can'' enjoy puns and he even makes some himself in the game. Papyrus only specifically dislikes ''Sans's'' jokes, but since Sans is constantly annoying Papyrus with his jokes, it looks like Papyrus has a problem with jokes, especially puns.
** It's very common for critics of the game to accuse it of BlamedForBeingRailroaded for the Genocide Route, ignoring the fact that the player can terminate the Genocide Route at any time (with much of it being a slog that the player needs extreme determination to overcome), and much of the YouBastard moments from that route being entirely in-universe from the monsters having [[SurprisinglyRealisticOutcome surprisingly realistic reactions]] to the player's rampage (as opposed to the game itself accusing the player of being a psychopath, as they often imply). Sans and Flowey do both accuse the player of only massacring everyone because they were bored and wanting to see every possible route (with Flowey also even calling out people who watch gameplay footage of the Genocide Route but are too afraid to play it themselves), but both of these are more just incredibly dark LampshadeHanging than actual judges of the player's character.

* {{Squick}}: During the hangout at Undyne's house, if Frisk flirts with her[[note]]point to her after she instructs the player to point to what they want[[/note]], Undyne asks incredulously if they're flirting with her and has a disturbed look on her face. If you do it again, she just continues to look disturbed until you point to something else.

** Red, an additional humanoid member of the Royal Guard from the fangame ''VideoGame/UndertaleRed'', is perhaps one of the most well known [=OCs=] in the entire fandom. She frequently appears in fancomics, and the devteam of another well-known fangame, ''VideoGame/UndertaleYellow'', hinted she'll have a cameo in the complete version of the game.

** After the Version 1.01 patch released in January of 2016, modified content in the game added stronger implications that Sans [[spoiler:is related to Gaster in some way, possibly as family]]. This has caused a lot of people to jump off the Sans/Gaster ship.

** A surprisingly common belief in gaming circles is that the game was made with UsefulNotes/RPGMaker. It was actually made entirely in [[https://en.wikipedia.org/wiki/GameMaker_Studio Game Maker Studio]]. While it is true that RPG Maker has been purpose-built for creating the sort of UsefulNotes/{{SNES}}-era JRPG ''Undertale'' has clearly been InspiredBy, it doesn't handle real-time action well: though there are some ActionRPG games made with it like ''VideoGame/{{Avarice}}'' (or even a straight-up ShootEmUp like ''VideoGame/SkyE''), its turn-based battle interface is quite rigid, and interspersing it with the real-time dodging segments that became ''Undertale's'' calling card would have been too complicated to bother with.

** ''Undertale'' was a well-received game internationally, but it has especially huge followings in South Korea and Japan, gaining a large amount of support from those in the latter country's gaming industry. This led to an official Japanese translation and a Korean fan translation, as well as ports for UsefulNotes/PlayStation4, UsefulNotes/PlayStationVita, and UsefulNotes/NintendoSwitch, further boosting the game's popularity there. It also received detailed entries in the ''Website/{{Pixiv}}'' dictionary. And [[https://www.youtube.com/watch?v=srZdDAJbHfc a full orchestral concert]] in Tokyo.

** The UsefulNotes/PlayStation4 and UsefulNotes/PlayStationVita versions had to make many technical changes to account for both the differing hardware and Sony's guidelines. And yet, for the most part, they managed to maintain the overall experience of the PC original. These two versions were also released on physical media, a contrast to the digital-only PC version.
** The UsefulNotes/NintendoSwitch and UsefulNotes/XboxOne[=/=]UsefulNotes/XboxSeriesXAndS versions are similarly polished and even add new content in the form of their unique Dog Shrines. The Switch version adds an ''entire optional boss'' in the form of Mad Mew Mew (which unlocks after beating Mettaton EX), while the Xbox versions have a [[BettingMiniGame casino slot machine minigame]] in its place.

** [[https://www.youtube.com/watch?v=P0PpyUsvT9w "Metal Crusher"]] bears a resemblance to the [[https://www.youtube.com/watch?v=z3ZiVn5L9vM&t=3s "A-Type" theme]] from the UsefulNotes/GameBoy version of ''VideoGame/{{Tetris}}'', which is itself [[PublicDomainSoundtrack a rendition of the Russian folk song "Korobeiniki"]]. Mettaton's other theme, [[https://www.youtube.com/watch?v=2TgO-tN5wAM "Death by Glamour"]], sounds a lot like [[https://www.youtube.com/watch?v=FT6PZUTdd04 the Waluigi Pinball theme]] from ''VideoGame/MarioKartDS'', and like the songs above, [[https://soundcloud.com/theniftytable/death-by-pinball-waluigi-pinball-undertale-style-v20 they combine together quite well.]]

* WhatDoYouMeanItsForKids: ''Undertale'' is intended to be a family-friendly game (and really, even such notoriously nightmarish sequences as [[spoiler:Photoshop Flowey and the True Lab]] aren't that much worse than what's seen in, say, ''VideoGame/{{Kirby}}''), to the point that Toby Fox encourages using an alternate tag on Rule 34 posts to hide explicit content from younger players. However, many who have embarked on a No Mercy route will say that it pushes the boundaries of "family-friendly" to their limits. [[spoiler:The game fully allows you to murder every last member of the game's lovable cast if you want to, ultimately enabling an EldritchAbomination in the form of a cute child to break free and destroy everything in the game world.]] The game also touches on extremely dark themes to varying degrees of subtlety - multiple characters are suggested to be suffering from depression and other serious mental illnesses, and the specific act of suicide is touched upon no less than four times[[note]]Five depending on how you interpret [[spoiler:Asriel's comment about why Chara climbed Mt. Ebott]][[/note]], with the two most explicit and unambiguous examples [[spoiler:involving characters who are ''children''.]] What's the ESRB rating for the [[UsefulNotes/PlayStation4 PS4]] and [[UsefulNotes/PlayStationVita PS Vita]] versions? [=E10+=]! Possibly FridgeBrilliance, since the two bosses exclusive to this route are NintendoHard enough to test the patience of many ''adult'' players, it's unlikely a little kid would actually see them through to the end until they're older. A parent could also make a point that even if it does offer such family unfriendly options, [[WhatTheHellPlayer the game condemns such actions harshly]]. Unlike, say, ''VideoGame/GrandTheftAuto'', the game itself scolds you as early as the Ruins for acting violent.

** When you first fight Mettaton, one of his questions is [[MakesJustAsMuchSenseInContext "Would you smooch a ghost?" and all the answers are "Heck yes!"]] Thanks to that, Mettaton/Napstablook have a fair amount of followers on Tumblr. Some even draw Napstablook as a robot called "Napstabot", with a similar style to Mettaton. [[spoiler:The real reason is probably that Mettaton was created by merging the soul of a ghost with a robot body, something not revealed in most endings. Ditto for why Napstablook's call-in in the bloodless conclusion to his boss battle starts to sway him. Of course, [[RelativeError the fact that they're cousins]] has [[AbandonShipping deterred quite a few people]].]]
** Mettaton/Papyrus is also quite popular, due to [[LargeHam their]] [[{{Camp}} similar]] [[AwesomeEgo personalities]] and because of a ''single'' line where Papyrus mentions that Mettaton is his "[[OverlyNarrowSuperlative favorite sexy rectangle]]".

* UnintentionallySympathetic: In a Neutral run, the human child can come off as this. The first monster they encountered was [[FoulFlower Flowey]]. He gave the impression the underground is a dangerous “kill or be killed” place with monsters popping out of nowhere to attack the child, and the talk of collecting human souls does not help disprove the monstrous flower’s words. They do not harm monsters on the map, showing they do have a distinction of combatants and non-combatants. Also, while they can resurrect from death, this would not undo any mental trauma that would happen from the event, especially considering the child’s young age. While they do leave the Underground a worse place [[spoiler:and become a bit more sociopathic at the end of their journey]], the violent actions the child takes to escape the underground can come off as not as unjustified as the game tries to paint. Not only this, but the player character is stalked around the underground by Undyne, who thinks of herself as a hero despite trying to kill a child (and everyone else praises her as a hero, too). Nearly everyone you meet, barring Papyrus and Undyne's fan, engage in morally dubious acts towards the child, from death threats to attempted murder to threatened abduction.

** Although she's by no means a hated character, some people view Toriel as such. While Asgore has a complex sense of morality in that he doesn't want to bring anyone to harm, but feels he has to do so for the sake of his people, as well as trying to delay the inevitable, Toriel's sense of morality is much more [[BlackAndWhiteMorality simple and closed-minded]], thinking that Asgore is an irredeemable monster for doing something he didn't even want to do in the first place. Even her compromise of Asgore crossing the barrier and taking six other souls is flawed, as while Asgore ''did'' take the longer, more arduous route, Toriel is [[FailedASpotCheck completely forgetting about what happened to her son after he crossed the barrier with innocent intentions]]. It also doesn't help that once you fall into the Underground, Toriel's first instinct is to take you in, presumably for the rest of your life.

* HardToAdaptWork: Despite a devoted fanbase, resonant themes, and the potential for gorgeous visuals, a faithful adaptation of ''Undertale'' to a non-interactive medium would be exceedingly difficult. The story is intimately tied to video game mechanics as SaveScumming is a recognized in-universe phenomenon. The StoryBranching also poses a problem since an adaptation would necessarily excise important material included in the branches that aren't adapted. Most pointedly though, much of the emotional torque of the original game relies on the PlayerPunch to end all player punches, which would be difficult to pull off in a non-interactive medium where the audience is not responsible for the actions of the characters: [[spoiler: the entire game is a Deconstruction of the SociopathicHero tendencies of many [[RolePlayingGame Role-Playing Games]], a genre in which executing enemies in combat is expected and unremarkable, while in [[StealthPun another medium]] it would be harder for the audience to sympathize with Frisk slaughtering RandomEncounters, if the creators wanted to adapt the Genocide Route]].

** A tag glitch on [[Website/FanFictionDotNet FanFiction.net]] once resulted in "Sans" being listed as a pairing for one story. Just Sans, by himself. This became a fandom in-joke, and Toby Fox even once joked that it was his favorite ship.

** It's very common for critics of the game to accuse it of BlamedForBeingRailroaded for the Genocide Route, ignoring the fact that the player can terminate the Genocide Route at any time (with much of it being a slog that the player needs extreme determination to overcome), and much of the YouBastard moments from that route being entirely in-universe from the monsters having [[SurprisinglyRealisticOutcome surprisingly realistic reactions]] to the player's rampage (as opposed to the game itself accusing the player of being a psychopath, as they often imply).

** Despite being the most notable RPG to allow non-violent ways to deal with monsters, ''Undertale'' isn't the first RPG to do so. ''VideoGame/PhantasyStarI'' had the ability to talk to certain enemies and talk them out of fighting, though this mainly applied to [[WhatMeasureIsANonHuman humanoid enemies]]. ''VideoGame/UltimaVI'' had the ability to make it through the entire main quest without killing a single enemy through liberal abuse of invisibility rings and potions; similarly, ''VideoGame/QuestForGloryI'' lets you do the same via lots of sneaking.

* ItsEasySoItSucks:
** Some people think ''Undertale'' is a bit too easy on the Neutral and Pacifist routes. While the fact that you only have 20 HP on the latter makes things harder, some fights only amount to waiting out the enemy or performing relatively simple sequences of ACT commands, so there's less strategy involved in going on the offensive, and in the final boss on the latter route, [[spoiler:you're automatically revived if you die]]. The Genocide route has two of the hardest bosses in the game, especially the final boss, but as you can see elsewhere on this page, there are reasons why a lot of people don't want to play it.
** Likewise, other than the two [[NintendoHard impossibly difficult]] bosses on the Genocide route most of the enemies can be killed in one hit and most puzzles are already solved or deactivated, leading others to consider the Genocide route as being too easy and, unlike the Pacifist or Neutral routes, without any sort of feel-good reward for the hair-pullingly frustrating parts. To be fair, [[InvokedTrope this is completely intentional]], and important to the game's message - if the Genocide route was any fun, its meaning would be all but lost.

* ShipMates: [[OfficialCouple Alphyne]] generally goes well with any other ship, such as [[OddFriendship Soriel]] and [[ShipsThatPassInTheNight Papyton]]. Alternatively, those who prefer Toriel and Asgore getting back together either end up shipping Sans with a different character or have him be AloneAmongTheCouples (which is something that he probably wouldn't mind, see ShippingGoggles below).
* ShippingGoggles: Soriel (Sans/Toriel) is an immensely popular ship despite Toby saying that Sans is canonically too lazy for a romantic relationship of any kind. Therefore, the few interactions they have in canon would have to have some goggles applied to be shipped.

** In terms of individual characters, [[RidiculouslyHumanRobots Mettaton]] consistently ranks among Japanese fans' [[EnsembleDarkHorse top characters]], due to a combination of his AntiVillain nature, being the Underground's designated {{idol|singer}}, and his very [[InTouchWithHisFeminineSide effeminate nature]].

* GermansLoveDavidHasselhoff: ''Undertale'' was a well-received game internationally, but it has especially huge followings in South Korea and Japan, gaining a large amount of support from those in the latter country's gaming industry. This led to an official Japanese translation and a Korean fan translation, as well as ports for UsefulNotes/PlayStation4, UsefulNotes/PlayStationVita, and UsefulNotes/NintendoSwitch, further boosting the game's popularity there. It also received detailed entries in the ''Website/{{Pixiv}}'' dictionary. And [[https://www.youtube.com/watch?v=srZdDAJbHfc a full orchestral concert]] in Tokyo.

** Attempting a Pacifist run after finishing a No Mercy run elevates this to SpaceWhaleAesop: "If you have the power to rewind time and you abuse it too much, [[spoiler:an evil spirit will steal your SOUL and kill everyone you ever cared about]]." On the other hand, this could be interpreted as "Some mistakes are [[MoralEventHorizon too terrible to ever be undone]]. Sometimes things can't be completely fixed."

** On a No Mercy playthrough, most of the background music is slowed down drastically, becoming especially groaning and dirge-like when the player is about to commit a MoralEventHorizon of some kind. In most situations, this fits the atmosphere of the player indiscriminately slaughtering anything in their path... but it fails to make the Temmie themes any less goofy-sounding.

** If you're not doing a Genocide or a very violent Neutral run, there's the monsters who try to kill you. The story treats any killing of a monster as something [[MoralEventHorizon horrible]]... But plenty of these monsters are actively trying [[WouldHurtAChild to kill a child]] [[spoiler:to harness their SOUL to help Asgore commit genocide on the human race]]. While any YouBastard comments are accurate when it comes to the ''player'', InUniverse the vast majority of monsters don't know about the player nor do they know that you can reset, and yet they act like this moral DoubleStandard they're holding you to is an inherently obvious truth rather than something brought on by extreme and uncommon circumstances they don't know about. Even though BlueAndOrangeMorality is sometimes at work because some monsters don't realize their "attacks" are harmful, it's not the case for all of them; a few are explicitly stated to be hired mercenaries, meaning they're willing to kill a child ''for profit''!

** Although she's by no means a hated character, some people view Toriel as such. While Asgore has a complex sense of morality in that he doesn't want to bring anyone to harm, but feels he has to do so for the sake of his people, as well as trying to delay the inevitable, Toriel's sense of morality is much more [[BlackAndWhiteMorality simple and closed-minded]], thinking that Asgore is an irredeemable monster for doing something he didn't even want to do in the first place. Even her compromise of Asgore crossing the barrier and taking six other souls is flawed, as while Asgore ''did'' take the longer, more arduous route, Toriel is [[FailedASpotCheck completely forgetting about what happened to her son after he crossed the barrier with innocent intentions]]. It also doesn't help that once you fall into the Underground, Toriel's first instinct is to take you in, presumably [[StockholmSyndrome for the rest of your life]].

*** Released in December 2015, the fangame VideoGame/UndertaleRed revolved around a ghost possessing a humanoid doll.
*** Released the same month, in the cover album ''[[https://determination-ut.bandcamp.com/album/determination Determination]]'' he made alongside the electro artist Amie Waters, [=RichaadEB=] made a metal reprise of "Dummy!" called "[[https://determination-ut.bandcamp.com/track/electric-balboa Electric Balboa]]", which (before the transition to the next song) ends on... [[CatGirl meows]].

** In December 2015, [=RichaadEB=] and Amie Waters released a metal and electro [[https://determination-ut.bandcamp.com/album/determination cover album]] of the game's tracks. Near the end of "[[https://determination-ut.bandcamp.com/track/electric-balboa Electric Balboa]]" (Mad Dummy's battle theme metal reprise), you can hear meows. Guess [[CatGirl which body the ghost takes]] in the UsefulNotes/NintendoSwitch version?

** ''VideoGame/LiveALive'' has an entire chapter where your encouraged not to kill ([[WhatMeasureIsANonHuman human]]) enemies and instead find other ways to sneak around and avoid fighting them. Getting the best ending in the chapter requires not killing any of the humans in the castle, while going out of your to kill everyone nets you the worst ending. Considering Toby has cited ''Live-A-Live'' as an inspiration for ''Undertale'', this probably isn't a coincidence.

** Temmie is a cute cat-dog hybrid creature with long hair, who wears a striped shirt and who makes funny faces, but also a young woman who works as a shopkeeper to afford college studies. This plot point gives fanartists the ideas of drawing her as a more conventional dog and CatGirl (either UsefulNotes/{{Furry}} or LittleBitBeastly), transforming her funny clothing as a [[SexyShirtSwitch more skimpy one]], and suggesting [[SexualEuphemism faster ways she could pay her tuition fees]].

*** LetsPlay/{{Markiplier}} had an equally controversial first run on the game, as when he got to his second video, people slammed him for not using the accepted {{fanon}} voices, going so far as to [[DisproportionateRetribution give him, his mother, and his dog death threats]]. This convinced him to stop playing the game for over a year, only to return in October 2016, but doing it in one go on a livestream and without listening to the fans.