Undertale / Tropes G to N

You can view the main article here.

Tropes A here.

Tropes B here.

Tropes C-F here.

Tropes G-N here

Tropes O-Z here.

Note: "No Mercy" and "Genocide" are two names for the same, officially unnamed, route of the game.

---

Trope G

• Game-Breaking Bug:
  • Well, diminishing the experience of one small part of the game, at least — Muffet's "pet" attack causes severe slowdown on some systems, and nobody is quite sure why.
  • Entering "Gaster" as your name in the PS4 and Vita versions will crash the game, rather than restarting it like in the PC versions. Given the nature of W.D. Gaster, it's quite likely this is intentional.
• Game-Over Man:
  • Under most circumstances, the text on the Game Over screen is accompanied by Asgore's voice grunting. The dialogue is eventually revealed to have been said to the Fallen Child on their deathbed.
  • Being defeated by the Neutral Final Boss causes him to taunt you during the Game Over screen after Asgore says his usual line impersonating Asgore to rub it in further.
  • During the final boss of the No Mercy route, trying to spare the boss at a specific point will cause him to kill you with an unavoidable attack. The resulting game over screen will have Dogsong play instead of the regular Game Over music while the boss will assert that, after all of your genocidal actions, he refuses to allow the battle to resolve peacefully.
• Gameplay and Story Integration:
  • Getting a combination of endings affects the outcome of another. In the Genocide ending, the Fallen Child kills everything and decides to move on to another world… the reset world of Undertale, which would only reset if you took a Deal with the Devil with them. Doing a Pacifist run afterwards heavily implies the Fallen Child's still in control, has taken down every main character, and is moving on to the surface world… and other worlds.
  • On the route for the Golden Ending, killing any monsters from the True Lab onwards, including the True Final Boss, will ruin the point of it being a Pacifist run. The game still lets you try, however. Attacks will just miss, partially because you wouldn't have the will to kill anybody at this point, partially because said monsters are either phantom-like in nature or a physical god.
  • To a smaller extent, conversing with Undyne on her date reveals that she'll probably never let Papyrus into the Royal Guard, but she assures it's not because he's physically incapable, in fact, he's "actually pretty freaking tough!" It happens to be true; by checking their stats in-game prior to patch 1.001, it shows that Papyrus has 8 ATK and 2 DEF, while Undyne has 7 ATK and 0 DEF. Following patch 1.001, Papyrus's ATK and DEF are both 20. Undyne's stats by comparison are now 50 ATK and 20 DEF, but still read 7 ATK and 0 DEF in the code.
  • If you chose to kill Undyne during a non-Genocide run, she will continue attacking for a few rounds after her HP runs out, but her attacks will get progressively slower, while sad music begins to play in the background.
• Gameplay and Story Segregation:
  • The boss fight against Mettaton EX has an alternate Guide Dang It! pacifist win condition which involves very quickly getting the ratings above 12000. Even if you managed to win the fight fast enough so that Mettaton EX's limbs are still on his body, his overworld sprite still portrays him without limbs during the cutscene that follows.
  • At various points throughout the game, the player is given the option to FIGHT a given character during a cutscene. If the player chooses that option, the basic slashing animation will be used for the attack regardless of whatever weapon you actually equipped. At the very end of a No Mercy run, the Fallen Child will also make the decision for you.
  • There's one point where Flowey doesn't react the way you would expect him to after a reset, which makes meeting him after the reset make less sense. If you abandon a Genocide run (by resetting, since you can't get back onto the Neutral path by that point) after he realizes you're going to kill him, or even moreso if you take the absolute last chance and exit the game before you cut him down in the ending, he doesn't have any unique dialogue about his brush with death, instead recycling his generic dialogue for abandoning the Genocide route where he's angry at you for stopping. On its own, this isn't that bad, but given the heavy Gameplay and Story Integration and massive amount of Developer's Foresight, the absence of a response to that scenario is very noticeable.
• Gameplay Roulette: While the game is mostly presented as a JRPG, each enemy you battle in Undertale has at least one unique bullet hell-style attack that you must defend against, and each one has a unique text-based "puzzle" you must solve in order to spare them. In addition to this, the Underground itself is absolutely covered in puzzles that must be solved in order to get from place to place, and the game tends to take on horror-like undertones at the end of each route. There are also short mock-dating sim segments that the player can do with a few of the characters.
• Gender-Inclusive Writing: The main character, Napstablook, Monster Kid, and the Fallen Child are only ever referred to using gender-neutral pronouns.^note It also makes translations to other languages outside English, Japanese, Korean, and Chinese next to impossible, since most languages don't have this.
• Genre Deconstruction: Although the game serves as a deconstruction of choice-driven video games as a whole, it puts specific scrutiny on RPGs, breaking down and shedding new light on some of the most fundamental mechanics in the genre.
• Genre Roulette: Most routes of the game are primarily an adventure/comedy, but with more than their fair share of tragedy and horror thrown in, often with very little warning. Take the genocide route, however, and the game becomes so relentless and unapologetic in these latter elements that it's barely recognizable as the same game anymore.
• The Ghost: A recurring Easter Egg in certain routes (depending on the game's internal "Fun" value) has the Clam Girl NPC repeatedly reference someone named Suzy, who is allegedly her neighbor's daughter; however, said character never actually appears in-game. If the Nintendo Switch version of the Easter Egg is any indication, that may well be for good reason.
• Gilded Cage:
  • Toriel's home is a lovely place to live in, but due to her extremely protective nature, she doesn't want you to leave, opting for dodging the topic, excusing herself to leave, and pleading with you. When all else fails, she physically stands between you and the only passage out of the Ruins.
  • The Underground in general is a slightly larger cage. The monsters seem to have little to no trouble with infighting or providing for themselves, but they're still living in a fairly small area with no view of the sun or stars. The populace has a widespread sense of hopelessness, both for living meaningful lives underground or ever reaching the surface.
• Given Name Reveal:
  • The player character's name is actually Frisk, and the character you named at the beginning is really the Fallen Child.
  • Flowey's true name is Asriel Dreemurr, making it clear he's Asgore's lost son and that he Came Back Wrong after his death.
• The Gloves Come Off: The final battle against Sans at the end of a Genocide run. The game makes it pretty clear that it is done fucking around.
• Glowing Flora: A lot of places in Waterfall (and a secret location in Snowdin) contain bioluminescent mushrooms that emanate a light blue glow. They can be turned off and on when interacted with.
• A God Am I:
  • When you initially defeat Photoshop Flowey in the Neutral run, he declares he is the God of this world. Of course, this is right before the Human SOULs he stole rebel against him.
  • The final boss of the True Pacifist run proclaims himself to be "The Absolute God of Hyperdeath" after gaining nigh-omnipotent power from absorbing the six human souls as well as the soul of nearly every monster in the Underground.
• Golden Ending:
  • The Pacifist route ends with everyone down to the last random battle alive and happy, all the bosses becoming friends with each other, and the villains (such as they are) acknowledging their mistakes and prepared to seek redemption if they didn't earn it already. And the Playable Epilogue shows how happy all the monsters are with their new lives. The only dark patches are that Asriel is ultimately resigned to the fate of turning into Flowey once more, and nothing prevents you from resetting the save file and erasing all that happiness, though the game actively discourages you from doing so (ironically via Flowey himself begging you not to do it)^note If you really, really want to, you can make a copy of the Pacifist route save files and keep them around!.
  • Somewhat interestingly, there's a Golden Ending within the Golden Ending. If you ACT with monsters in such a way that they're happy with you when you spare them (and monsters you never encounter aren't shown at all), the text in the credits roll will show how successful they were at integrating into human society, with white text being "doing alright" and yellow meaning "found a perfect calling".
  • This is parodied with one of the neutral endings. Sure, you killed everybody who was important in the underground, but having a lazy dog as a president has led to the best life possible for everybody. Thanks.
• Good Feels Good: Whenever the game isn't judging and/or guilt-tripping you for being a jerk, it's instead encouraging, supporting, and appreciating you for being good, or even just not being bad, and it's very good at making you care about your choices.
• Go Out with a Smile:
  • If you resolve the Boss Battle with Toriel by killing her, she'll acknowledge your strength. Whether that smile is sincere depends on the circumstances when you strike the lethal blow.
  • Mettaton, if you get the Ratings past 10,000. It's only temporary, though… he's just out of battery life.
  • Mettaton also does this if you kill him for real on the neutral run, because even if he didn't get to be a star on the surface, at least he got to perform for one human.
  • Mettaton does this a lot. If you play a No Mercy route up until him, but flub the requirements on his boss battle (because you didn't kill everything in his zone before encountering him), he'll say that he can tell that you struck him with less than absolute hatred, and that he can therefore die peacefully knowing that while you might kill Asgore, humanity and Alphys are safe.
  • Both Papyrus and Sans keep their permanent skeletal grins as you kill them in the genocide route; Papyrus because he still believes you can be a better person, and Sans because he doesn't want to give you the satisfaction of seeing how much pain he's in.
• Gray-and-Gray Morality: The Neutral routes. On one hand, the Player Character is trapped in a fairly hostile world where most monsters are out for their blood, even if the monsters themselves are well intentioned extremists trying to secure their own freedom from the Underground, or attack due to animal instincts. On the other hand, you yourself can choose to respond to this hostility in a ruthless manner by using lethal force. At best, this only results in you causing the death of the Monster King Asgore, as he must be fought in order to finish the game, and possibly Flowey too, after you fight him. At worst, you've left a massive trail of bodies behind you and thrown the kingdom of monsters into despair and disarray. Most new players will likely end somewhere in-between on their first run, making them Anti Heroes in a world where Everything Is Trying To Kill Them.
• Great Offscreen War: The backstory of the game had a war between monsters and humans that resulted in the monsters being sealed away in the underground. Even though monsters are said to be almost helpless in the face of a sufficiently powerful Killing Intent, humans feared monster-kind's ability to absorb the power of human souls and grow stronger.
• Green Gators: Bratty is a bluish-green alligator monster.
• Grief-Induced Split: Asgore and Toriel lost both their children in one night—their adoptive child to illness, and their son who was killed by humans when he tried to take his sibling's body back to their village to fulfill their Last Request to see the flowers there again. Asgore, beside himself with grief, declared war on humanity on behalf of his kingdom and made it law that any human who came there would be killed. Toriel, disgusted and horrified by this (especially since their adoptive child had been human), left him.
• "Groundhog Day" Loop:
  • Flowey mentions at several points that before you showed up, he used his ability to SAVE to toy with all the characters this way, altering reality so that all of them are technically in one without even knowing it. Assuming that it worked the same way it does when you SAVE, none of them have any direct memories of previous versions of the timeline, but do have foggy recollections of them similar to deja vu or half-forgotten dreams.
  • On a more meta level, because every subsequent playthrough on the same save file canonically takes place in the same in-game universe, you can perpetuate this cycle yourself by playing the game and then resetting. Once again, with the exception of Flowey, none of the characters remember this directly, but do have enough awareness of it to alter their dialogue in several places.
  • Both these examples have a significant curveball thrown into them: Sans. Sans is aware of the fact that he exists in a universe that can be altered and reset at any given moment, and how significantly it affects his character seems to vary based on player actions and Alternate Character Interpretation. At the height of his despair at the end of a Genocide route, he tells you that living with his knowledge has left him in a state of existentially-driven apathy and depression. He then goes on to say that even getting the Golden Ending and making it to the surface world doesn't appeal to him anymore, because it would just look like a setup for a Hope Spot in his eyes; the player is inevitably going to reset sometime anyway, right? As a result, the only way to truly free him from this loop is to never play the save file again after getting the best ending, a move that the game actively encourages you towards and many players have admitted to doing, some going so far as to preserve the file in a thumb drive just to be safe.
• Guide Dang It!:
  • Figuring out how to defeat the bosses non-lethally in many cases involves paying close attention to clues from other NPCs and to how the boss reacts to different actions. The only way to spare Mettaton EX, for instance, is to either get your ratings above 12,000, or survive until his limbs fall off and get your ratings above 10,000. You're never given any obvious hint for this, and new players might assume the ratings were just for show.
  • Sparing Undyne — the game doesn't really give much of a hint that you even can run from her, or that if you do, that it will allow you to spare her. Typically, you don't run from bosses in these kinds of games.
  • Following the rule of "Never use 'FIGHT', do the major sidequests" will get you most of the way to the Golden Ending, but this has one possible exception: said ending cannot be the first one gotten, because one of the required sidequests doesn't unlock until you've seen another Neutral ending (if you've been pacifistic for the whole game, you can reload your last save instead of restarting). As a result, you must go against Asgore for a Neutral Ending and use the 'FIGHT' command, although thankfully you can still spare him after fighting.
  • There's a way to get into Sans's bedroom. Once you reach the Last Corridor in a Pacifist run, talk to him to receive his judgement 4 times by reloading and he will give you the key. It does make sense, but only in retrospect — who would think to do something like that if they didn't already know the game acknowledged it?
  • In the Pacifist epilogue, you can find Asriel all the way back at the patch of golden flowers in the Ruins where the game started, where he gives backstory about Chara and realizes they weren't as good as he remembered. The Ruins are inaccessible until the epilogue, and he only appears before you see the credits, since otherwise he'll have turned back into a flower.
  • Getting the yellow flavor text for all the monsters in the Pacifist Ending credits. Most of them aren't so bad since they can be gotten either by experimenting or are required to spare the monster without having to fight. However, there are a few of them that are pretty non-intuitive. Some particular examples include Ice Cap, who you can spare by ignoring two times but must steal its hat and compliment to get the yellow name, and Aaron, who requires you to change the background music in Napstablook's house and then encounter him outside with that background music still on to get his yellow credits. Aaron is the only enemy in the entire game to have this requirement in events outside of battle. Mad Dummy also stymied the community for a while, as you have to talk to them exactly once during the battle, and there's no obvious connection between this action and either form of their credits text.
  • Arguably, the way to achieve the worst ending (i.e. No Mercy/Genocide route). While the game guides the player quite clearly to the best ending (Flowey always tells you what you missed at any neutral ending you get, unless you've killed him), even the existence of such a worst ending is not clearly hinted, nor the way there instructed. This is deliberate, because it means that there is nearly no chance a player will end up on the route accidentally; a major theme of the route is that the player themself is choosing to kill absolutely every monster (despite it being unnecessary and tedious) because they want to know what happens if they do.
  • The Kickstarter reward monsters, except for Muffet, are extremely difficult to actually see in-game. So Sorry is found in a hidden room that the player has no reason to believe exists and only appears on one day of the year at an extremely specific time, down to the exact minute. Glyde doesn't appear in a hidden room and has no real-time requirement, but the room it can be found in is out of the way and very small. Additionally, Glyde is an ordinary enemy and not a boss like Muffet or So Sorry, and will only show up if the player walks around in said room for an unreasonable amount of time. To top things off, once the player spares or kills Papyrus, Glyde will never appear again.

Trope H

• Half the Man He Used to Be:
  • In the No Mercy route, Undyne takes a blow for the Monster Kid that visibly cuts her battle sprite in two, from shoulder to hip. Her upper half begins to slowly fall off… until she reforms herself for the real boss battle.
  • The final boss of the No Mercy route has his torso diagonally slit in half all the way from his shoulder to his hip after you land the killing blow on him.
• Hammy Villain, Serious Hero: Among the foes that the perpetually poker-faced Human Child/Frisk has to contend with during their adventure in the Underground are Flowey, a smarmy sociopath of a flower with a penchant for Evil Gloating and making terrifying Nightmare Faces, and Mettaton, a Killer Robot with the personality of a game show host and a humanoid form reminiscent of a glam rocker.
• Hand Wave: Whenever the player is slightly out-of-bounds (when it should be impossible), "magic glass" appears underneath them so they won't be walking on air.
• Happily Ever After: Everyone in the Golden Ending, except Flowey, and even he's better off than he was at the start. From Hotland's two royal guards to Alphys and Undyne, almost every other monster and their corresponding Mind Hive Long-Lost Relative amalgamation, and possibly Asgore and Toriel.
• Hard Mode Mooks: Parsnik, Migospel, and Moldessa are stronger variations of Vegetoid, Migosp, and Modsmal that only appear in the Ruins on Hard Mode.
• Have We Met?:
  • In the True Pacifist Route, Toriel and Sans, who had never met in person, find each others' voices familiar and realize that they'd been acquainted for quite some time.
  • When you restart the game, any of the main characters that you had befriended in a previous playthrough will vaguely remember you. For example: when Toriel asks what your favorite is between cinnamon and butterscotch, she will instead take a guess, which will be whatever you picked in the last playthrough.
• Healing Boss: Attempted by Photoshop Flowey at the end of his boss battle. After exploiting SAVE files to attack Frisk, he uses one to heal himself to full health after you beat him. The souls he absorbed then revolt and tear him open from the inside, defeating him again and removing his power over the game itself.
• He Knows About Timed Hits: The monsters in the Ruins will gladly tell you all about hitting X to skip conversations, how a monster's name will turn yellow when you can SPARE it, and other helpful information. Of course, this extends well past the tutorial stage, leading up to the revelation that Flowey knows about and controls SAVE FILES in the final boss battle of the neutral route.
• Healing Checkpoint: They also serve as save points.
• Health/Damage Asymmetry: Justified: Though many monsters are a lot more powerful than humans, with characters like Undyne that can suplex boulders being fairly common, their genetic make-up causes them to take massive damage when hit by a foe with a lot of Killing Intent. Humans, meanwhile, can use determination to live through magical attacks that would otherwise prove incredibly fatal. Thus, this trope.
• Heartbeat Soundtrack:
  • A heartbeat plays in the background of the final scene of any Genocide playthrough, where the player has killed every single NPC the game allows.
  • In "But the Earth Refused to Die": If you listen closely, you can hear the hearts of everyone in the world beating as one.
• Hell Is That Noise: If you visit Napstablook, listen to one of their music tracks, keep it on when you leave, and go south, you'll encounter Aaron and Woshua. Their reaction is hilarious, and seeing the scene actually helps you get rid of Aaron quickly (and non-violently) if you run into him again.
• He Who Fights Monsters: A major theme of the game. By continually fighting literal monsters, even to the point of excess, they start becoming actively afraid of you and your capacity for cruelty. Especially apropos because you are fighting creatures called "monsters", yet can possibly end up more horrific than almost anything you encounter if you so will it. It gets even lampshaded by both Sans very early and Asgore very late that the player character can't even be recognized as a human, meaning they visually change into a literal monster as well.
• Heroic Sacrifice:
  • Toriel will let you kill her to prove that you are strong enough to survive the Underground.
  • Undyne will make a final stand against you in the Genocide Run rather than go into hiding with the survivors, in the hopes of protecting the monsters that haven't been able to flee from you and save the humans.
  • Mettaton will stay behind to stall you and buy time for Alphys and the other monsters to evacuate Hotland during a Genocide run.
  • Asriel after his Heel Realization decides to do the right thing and give all the monsters their forms back, at the cost of reverting back to a soulless flower. He also refuses to go with Frisk and his parents to the surface, because he doesn't want anyone to see him turn into a horrible creature.
• Heroic Suicide: Under certain conditions, if you spare Asgore, he starts dreaming about an idyllic future with you, his wife, and him living together as a family. ...But "that's just a fantasy, isn't it?" He tells you about the prophecy of a savior coming into the underground to free monsterkind, and that he believes that savior is you. He asks you to take his soul and cross the barrier, then he kills himself.

  Asgore: Ha... Ha... I'm sorry I couldn't give you a simple, happy ending... But I believe your freedom... is what my son... what ASRIEL would have wanted.

• Heroic Willpower: Prior to the True Pacifist final boss battle, the captured monsters use their powers to protect Frisk's soul. They each give a Rousing Speech that the human can defeat Flowey. Undyne is also fighting back.
• Hey, You!: Almost no one calls the Player Character by name, instead addressing them as "(the) human". This is a hint that the name the player comes up with isn't their name, but that of the Fallen Child. The only times that name is used are by Flowey/Asriel (who treats the player character as a Replacement Goldfish for the Fallen Child) and in the Game Over screen (whose dialogue is actually a memory of the Fallen Child that the player is experiencing). Once Asriel comes to terms with the fact that Frisk is not the Fallen Child, he decides to make Frisk's name known to all the souls he's absorbed before returning them, which causes everyone to start referring to them as "Frisk" rather than "human".
  Asriel: You're not actually Chara, are you? Chara's been gone for a long time.
• Hidden Depths: Every major character has more to them than meets the eye. However, due to the game's extreme level of sensitivity to player choice, it's literally impossible to explore them all in a single run. In particular, going full genocide results in a very strong example of The Apocalypse Brings Out the Best in People, exposing depths that would only be hinted at otherwise. On the flipside, just about everything about Flowey is kept hidden from the player until the end of a true pacifist run (though he also explains a lot about himself at the end of a Genocide run as well).
• Hidden Track: Only the first 77 tracks out of 101 of the soundtrack are available for preview on Bandcamp. The rest are hidden due to their spoiler-laden nature, and can only be legally listened to by purchasing the soundtrack.
• Hoist by His Own Petard:
  • Since the Mad Dummy has no interest in ending the fight peacefully, and is immune to physical attacks, the only way to stop it is to trick its little dummies it uses to attack into accidentally shooting it with magic projectiles.
  • Mettaton turns on Alphys when she recruits him to be the "bad guy" so that she can save you from him and he decides it's more fun and exciting to actually be the bad guy who doesn't create openings for her solutions. More notable in that she created his robotic body, which is the primary reason you can't defeat him, since you have no magic and physical attacks can't hurt him.
  • Likewise, Flowey, whom Alphys created from a large golden flower and unknowingly Asriel's dust, traps her and the other boss monsters when they gather to break up your fight with Asgore. Lampshaded when Alphys gets an Oh, Crap! expression right before Flowey captures everyone. However, this almost immediately gets turned on Flowey's head when his transformation back into Asriel Dreemurr causes him to inadvertently regain his compassion, allowing you to calm him down and help him pull a Heel–Face Turn, where he puts down the schemes he made as Flowey for good.
  • Your willingness to do a Genocide Run trips you up when you try to do a subsequent Pacifist Run.
• Hold the Line: Some bosses and encounters take longer to finish if you're trying to Spare them rather than fight. The player needs to keep hitting Spare (and/or use Act) and withstand waves of attacks until the boss is ready to show mercy (or accept it).
• Holiday Mode: A minor example: if you've gotten the True Pacifist ending, the Joystick Config menu will be different depending on whether it's spring, summer, autumn, or winter.
• Hopeless Boss Fight:
  • Photoshop Flowey plays with this. When you initially fight him, you can beat him on the first try, but the fight is set up so it seems that you're constantly at a disadvantage: in addition to the real-time battle being disorienting (because of the contrast with the rest of the game) and hectic, your health bar is also massively skewed and each hit you take halves your current health until a certain point, meaning you seem to be down to the last bit for most of the fight. What's more, you initially only do a single HP of damage whenever you use the FIGHT command, and Flowey seems to have thousands. However, you can't die in any of the SOUL segments, and each of them works as a checkpoint that stays completed even if you die. One final twist is when, after seemingly defeating Flowey, he reloads back to full health from the save state he initially saved at the very beginning of the battle, but is finished in a cutscene by the human souls he absorbed.
  • The final boss of the True Pacifist Route seems to present itself as this. You're even told, right before the battle, that it should be technically impossible to defeat him, and that's before he powers up. There is a catch to this. The player can't die. Every time your HP runs out, your heart refuses and you continue the fight. So it will continue until you win by saving all your monster friends… and, eventually, Asriel himself – you don't defeat him, you use his newfound power to feel love and compassion to remind him of why he's doing any of this in the first place.
  • And the No Mercy ending finishes the set. Except the "boss" is you. Because of your power to save and reset, there's no way the boss can actually defeat you, and they know it. The best they can do is to make the battle frustrating enough that you quit.
  • Downplayed example: While Undyne can be defeated in a Neutral route by attacking her until she dies, she's the only enemy outside No Mercy who cannot be spared by any means. Fortunately for players who are unwilling to kill her, she's also the only boss (other than Toriel) who can be run from…
  • Asgore seems to be this way in a Pacifist run. The 'Hope' in this situation wouldn't be to win, but to spare him and resolve the fight peacefully – and his first move on his first turn is to take his trident and shatter the MERCY button, removing it from the screen entirely. You're then forced to use the FIGHT button, possibly for the first time in the whole game, once AC Ting stops progressing the battle and you run out of items to use.
• Hope Spot:
  • Asgore inadvertently created one, in declaring war on the humans after his children's death and wanting six souls to cross the barrier, all the while unwilling to do the actual murder. His queen calls him out for this and this ended their relationship.
  • Sparing Asgore on a neutral-pacifist run; sure, you've given up hope of getting out of the underground, but you've ended his genocidal plan amicably and even seem to have found a new family in inclusion to all your friends, then Flowey appears and finishes him off, and things take a nosedive from there.
  • During the True Pacifist ending, Asgore gives a huge smile when Toriel returns to save you from him. She then shuts down his hopes of reconciliation by chewing him out and refusing to be even Just Friends.
  • For Sans, it's hoping during a No Mercy run that you will not kill all the bosses, so that he won't have to fight you.
  • For the Player, doing a Pacifist Run after No Mercy and the world has been ended. Surely you can make things right after going so horribly wrong. Unfortunately, you sold your and Frisk's souls to the Fallen, so that they appear in every subsequent run…
• Horrible Judge of Character:
  • Several monsters who assumed you were evil and attempted to kill you in a neutral or pacifist run will, in a No Mercy run, when the character is genuinely evil, instead be incredibly trusting of them and simply offer to let them go without a fight, only to be murdered in cold blood. Justified in that if you have been sparing everyone, you will continue to look like a human, but if you have been killing everyone, you slowly start to look monstrous. Humans, as per the narrative, are the enemies of the monsters. There are also a few monsters who are less this and more Genre Savvy, as they're aware that if they try to stand in your way, you will kill them, and they hope that by sparing you, you'll stop seeing them as an obstacle and move on.
  • Papyrus plays with this. If you do choose to spare him during a genocide run, he will admit that he was a little afraid that you weren't going to accept – and give – mercy, and is glad you did. There's also a little bit of implied fear of He Who Fights Monsters on the boss' end, as he's more willing to spare you and die than kill you in cold blood.
• Hostile Show Takeover:
  • At the end of your first Neutral run, Flowey ganks Asgore's soul (after killing Asgore himself, if you opted not to), steals the six human souls, and crashes the game. When you restart it, the intro story is interrupted by a glitchy mess, and the save file, instead of your name and location, now reads "Flowey: My World". Eagle-eyed players will also note that the game's title bar now reads "FLOWEYTALE".
  • After defeating the final boss in a No Mercy run, you no longer control your character in battle, the First Fallen Child does. Walking forward to talk to Asgore leads to attacking and killing him regardless of the player's inputs, and then doing the same to Flowey even as he begs for mercy. Upon killing him, the game will no longer return to the overworld, and instead shows a black screen — the battle screen with no enemies left to fight.
• HP to One: A number of bosses have attacks that reduce your health to 1, usually as part of Anti-Frustration Features since most of them could easily 1-hit KO a level one locked Pacifist player and having 1 HP gives you at least a chance to heal.
  • It's impossible to be killed by Papyrus, as an attack that normally would will instead bring your HP to 1, and the rest of his attack is halted so he can capture you.
  • Getting hit by any of Asgore's attacks will always leave you with at least 1 HP, unless it's at 1 already. Since he's unwilling to murder, he's holding back until he has no choice but to kill you.
  • The Neutral Route final boss Photoshop Flowey spams attacks and abuses savestates to leave you with 1 HP when he thinks he's won. Running into the circle of bullets while he's doing his speech doesn't hurt you and only annoys him. In fact, Flowey seems to be very fond of leaving you at 1 HP and gloating before sending a killing blow.
  • The True Final Boss pulls this off when trying to destroy the entire timeline. You're only alive because you're that determined. He will later exaggerate this trope by reducing your health to a minuscule fragment of a HP.
  • If you're on a Genocide Run, the final boss will inflict a poison-like, health draining status and throw attacks at you while you navigate menus, both of which will quickly drain your health to 1, but will never kill you (it would kill you in the beta, but player feedback changed it). Additionally, if you manage to survive his penultimate attack, the boss will repeatedly throw your SOUL against the walls of the bullet board in an unavoidable attack, dealing 1 damage each time, but also never reducing your HP below 1.
• Humans Are Bastards: The game builds it up this way at the start – the humans imprisoned the monsters at the start of the backstory because they feared a preemptive strike and decided to attack first. In fact, many people (like Undyne) assume you're a terrible person just because you're a human. This is later subverted: humans are extremely accepting of monsters in the epilogue, and judging by how fast monsters integrated into society, it seems like they want to repent for their previous actions. In fact, when you find out that humans killed a monster who was bringing the body of a human child back to the child's village, the narration states that they believed the monster had killed the child. The human you play as, Frisk, is even an All-Loving Hero by nature. The only human character in the story that qualifies as evil is Chara/The First Child or potentially the Player, and even their case is highly ambiguous: at best they're just a traumatized sociopathic Well-Intentioned Extremist^note and, according to some theories, the narrator of the game, and at worst they're a Manipulative Bastard-esque Woobie, Destroyer of Worlds who kicked off the entire plot purely for revenge. Either way, if you encounter them at the end of the Genocide Run, it's pretty likely that they've stopped being human entirely — and if the other characters' comments on how you look in their eyes through said run is any indication, so have you.
  • Throughout the Genocide Route, monsters have trouble recognizing you as human, implying that humanity is, in fact, something that's inherently good, and your horrible actions have turned you into something inhuman.
• Humans Are Special: Humans, unlike monsters, are mostly physical matter, making a human much stronger than an equivalent monster. Additionally, human SOULs linger after death; this allows monsters to steal their SOULs and use them as a power source, making the monster incredibly powerful. Most importantly of all, human SOULs possess a natural abundance of Determination, which is absolutely essential for your quest to empty out the underground, however you choose to do so.
• Humans Are Warriors: If you call her outside Gerson's shop, Undyne hints that the war between humans and monsters was a Curb-Stomp Battle thanks to this. It's easy to believe when you remember a single human child is capable of taking down the monster world's greatest warriors by themself, and that, unlike humans, monsters take (and give) more damage based on the level of killing intent behind the blow.
• Humans Kill Wantonly: There are many monsters trying to kill you. Maybe they want your soul so Asgore can break the barrier and free the monsters. Maybe they want to prevent Asgore from getting your soul and destroying humanity with it. Maybe they think that you're a horrible monster just because you couldn't afford to spend money on that overpriced bake sale. Or maybe they actually don't want to kill you, but are simply unaware that their actions risk hurting you. You, on the other hand? You kill because you can.
• Hyperactive Metabolism: Justified, at least somewhat (and Lampshaded), by a particularly curious monster in Grillby's: While human food needs to be entirely digested first, monster food (i.e. anything you consume in the game) immediately converts perfectly into energy upon consumption.
• Hyperactive Sprite: In battles, most enemies have a simple animation they repeat on loop, with only a few (most noticeably Toriel and Papyrus) that don't animate. It's lampshaded in a Pacifist victory against the Royal Guards, where 01 tells 02 how much he loves "bouncing and waving [their] weapons in sync", which, indeed, is what they do during the battle. It becomes downright surreal with Temmie, whose sprite constantly vibrates with excitement and whose face will eventually vibrate free of her body, and the closer Mettaton gets to attacking with his core for the second time in the main phase of his last boss fight, the faster he starts dancing, to the point of changing poses on every half beat of his theme.
• Hypocritical Humor:
  • If you go in Sans' room, Papyrus will call him immature… right before asking Frisk if they've seen his action figures.
  • If Mettaton catches you swearing in your essay answer, he delivers this line: "Oh my! This is a family friendly TV show." [ratings drop 150 points] "Now stand still while I murder you."

Trope I

• An Ice Person: Ice Cap attacks by firing spiky chunks of ice or sweeping icicles across the bullet board, and Gyftrot can attack with snowflakes.
• I Choose to Stay: While it is impossible to choose to remain with Toriel in the Ruins if you wish to progress in the game, in the True Pacifist Ending, you can choose to remain with her. You can also do this by sparing Asgore, giving up your chance to leave the Underground so that he can live. However, this one does not work out, as Flowey kills him, and even if he didn't, Asgore would not accept it anyways.
• If You're So Evil, Eat This Kitten!: In a meta sense, the game does this to the player if they're attempting a genocide run. Notably, you have to murder Papyrus in cold blood and attempt to kill the obviously defenseless monster child.
• I Gave My Word: In an optional conversation near the end of the Neutral run, Sans says that if he hadn't promised Toriel he'd leave any humans he saw alive, the player would be "dead where [they] stand." It is also the reason why he first fights the player near the very end of the No Mercy run: He had been trying to honor his promise to Toriel for as long as he possibly could, even in spite of the death and horror the player was inflicting upon his friends, acquaintances, and even family, but by the time you meet him before facing Asgore, he has realized that far too great things are at stake to allow a monster like the player to live. He pulls out all the stops to make sure that you don't get past him.
• I Love the Dead: Played for Laughs during Mettaton's quiz. One of his questions is "Would you smooch a ghost?" and all the answers are "Heck Yeah!" This becomes more significant after you learn Mettaton is probably Napstablook's cousin (thus, a ghost) in a robot body.
• I Know You Know I Know: If you've already befriended Papyrus in a previous run and restarted, he wonders if he's met you before.
  Papyrus: DO I KNOW THAT PERSON???
  Sans: do you not know who you know?
  Papyrus: PBPBPPBPT!! OF COURSE I KNOW WHO I KNOW!! I WANTED TO KNOW IF YOU KNOW... I KNOW WHO I KNOW AS MUCH AS I KNOW I KNOW WHO I KNOW! ... YOU KNOW?
• "I Know You're in There Somewhere" Fight:
  • Twice. The first is in the neutral ending, during the boss fight against Flowey, as you Act to help the human souls break free of his control. The second is in the true pacifist ending, during the boss fight against Asriel, as you Act to free the "Lost Souls" of your friends and calm down Asriel himself.
  • Happens in the No Mercy run, with the final boss pleading for you (as in, you, the player) to remember your humanity and lay your weapons down. Subverted in that, should you choose to spare him, he traps you and destroys your soul, killing you. Double Subverted since the only remaining way to turn back on your evil ways at that point is to quit and start over. On the Game Over screen, Sans reiterates this by telling you "if we're really friends, you won't come back".
• I'm Cold... So Cold...: You eventually encounter a monster whose check and flavor text is "It's so cold." She's one of the most pitiful fights of the game; her attacks are listless and a few don't even enter the battle box. Unlike the other amalgamates, Snowdrake's mother seems to barely even be alive.
• I Need to Go Iron My Dog: "I need to go to the bathroom" seems to be a catch-all for monsters excusing themselves but not having anything better to say, since monster food doesn't go farther than the stomach. Papyrus does it to excuse himself, then proceeds to jump out a window and run off, and Alphys does it and runs into another room to avoid having a panic attack (and it also disguises the fact that it's an elevator to the True Lab).
• Incompetence, Inc.: MTT Resort, as Burgerpants puts it, is a "Labyrinth of bad choices." Right as you enter the lobby, you're greeted by a fountain with the image of Mettaton spitting water right onto the carpet. The residents never get their room service, the janitor is so busy cleaning up his own messes that he can't clean anything else, the elevator's completely busted, and you have to reserve your dishes and silverware to eat at the restaurant. Not to mention that the store sells parfaits and burgers made out of sequins and glue. Burgerpants mentions that Mettaton vetoes any actual improvements they make because "that's not how they do it on the surface."
• Infinity -1 Sword: The Worn Dagger and the Heart Locket, which belonged to Asriel's sibling, the Fallen Child, are some of the strongest equipment in the game and the final pieces of equipment one can find on a normal or Pacifist run. They don't need to be bought, either, and are difficult to miss, ensuring the player at least has something for the end boss if they've been neglecting equipment thus far.
• Infinity +1 Sword:
  • On a No Mercy run, the Infinity-1 Swords are replaced by the Real Knife and The Locket, which are implied to be the same weapon and locket due to their identical location, just viewed differently by the more twisted narrration of the route. They increase your stats by 99, but by this point, there is only one enemy left, who's immune to their effects. The one time you really get to see the Real Knife's long-awaited power? When the Fallen Child slashes the world for endless damage!
  • The strongest piece of armor in the game which you actually do get to use is the Temmie Armor, and it is appropriately hard to get. First, you need to discover the secret Temmie Village. Then you need to buy the Temmie shopkeeper a college education (for 1000 gold). Only then will she sell you the armor… for 9999 gold! The price is reduced if you die a lot, but even after 23 deaths, it's still expensive at 750 gold.
• Improbable Infant Survival: No matter which path you take, Monster Kid always survives their close brush with death. In the pacifist/neutral path, either you or Undyne will save them from falling off of a bridge. In the Genocide path, Undyne saves them from you.
• Instant-Win Condition: Several fights can be avoided entirely by a single act.
  • Whimsun and Moldsmal don't want to fight at all. All you need to do is spare them, and the fight ends.
  • Muffet will let you go instantly if you eat the Spider Donut or Spider Cider during her fight, as it proves you did participate in her bake sale. Also, if you grind out the coins for it and buy one of the super-expensive items at the bake sale in Hotland, Muffet won't even take you into the battle system. She will also spare the player instantly if they're on a Genocide Route, because despite all the murder you've committed, you haven't harmed a single spider.
  • Downplayed in the True Pacifist final boss; if you eat the Butterscotch Pie while trying to save Toriel and Asgore, you'll be a single act away from saving them both. In the same battle, saving one of them will instantly save the other even if you didn't act on the latter. The same holds true for Sans and Papyrus.
  • Although not a single act, Mettaton EX ends his final boss fight if his ratings go above 12,000, or 10,000 if he lost his legs.
  • Any dog type enemy, including Endogeny, can be spared immediately with the stick.
  • Endogeny again, using the Hush Puppy. However, through hacking, it has been shown that it does not work on other dogs, despite claims that it neutralizes dog magic.
• Interface Screw:
  • Several bosses recolor your heart, which changes how you can move it while defending.
  • In an encounter with Pyrope, turning up the heat causes the text box and bullet area to wiggle in the heat.
  • Asgore starts out his battle by directly attacking the Mercy option, so you can't try to spare him.
  • The final boss of the No Mercy playthrough is capable of attacking you pre-emptively, ignoring Mercy Invincibility, and damaging you in between turns by targeting your cursor.
  • On the neutral path, after Flowey kills the king, the game window automatically closes. When reopened, the opening cutscene glitches out and then goes straight to his boss battle, a real-time bullet hell. The ACT and FIGHT buttons appear at regular intervals, and Flowey even abuses savestates to try and mess with you.
  • Should you encounter them, the first Fallen Child will give you a short speech, then seemingly attack the game itself, closing it almost instantly. When you reopen the game... you are greeted by nothing at all.
  • The amalgamations in Alphys's true lab all play with this in some way, like having glitched out names, overlapped speech bubbles, or bizarre and nonsensical actions.
  • Trying to Talk to Madjick will result in it spouting magic gibberish that confuses you, resulting in the SOUL controls being inverted until you either clear your mind (which can also be done before talking to prevent this) or spare it.
• Insurmountable Waist-High Fence: To a certain extent. In New Home, you come across a long chain blocking the way downstairs to progress, requiring you to explore the house more to find the two keys to unlock it with. Why the Child doesn't simply crawl under it or jump over it and ignore it is never elaborated on, even on the No Mercy path where they would likely much rather get past it and to the next battle as soon as possible.
• Inventory Management Puzzle: To a degree. The Child can only carry eight items at a time, not counting their current armor and weapon. This will fill up fast because of stockpiling healing items. To help out, the game provides a "Dimensional Box" in numerous locations that allows you to swap out items whenever you want, which is useful for storing specific foods for later events or for old weapons until they can be sold. The limitation of the box (it's only in a few select locations) becomes moot with Alphys' cellphone upgrade, which gives you permanent access to the box and a second one via the phone (though not during battles); you can't get this in a No Mercy run, but several more Dimensional Boxes appear near the end of the game as a compensation.
• Ironic Echo:
  • In the normal route final battle, Flowey taunts the player, challenging them to cry for help, for someone to save them, followed with "But nobody came". In the No Mercy Run, he himself describes this as his exact reaction upon first finding himself as a flower.
  • On one of the tapes with Dreemurr home videos, you can hear Asriel asking the First Child to "do their creepy face". In the No Mercy run, he, now in his Flowey form, eventually becomes terrified of you and angrily says: "S-s-stop making that creepy face! This isn't funny! You've got a SICK sense of humor!".
  • At the end of the normal route, Asgore introduces himself by saying, "Nice day today, huh? Birds are singing, flowers are blooming. Perfect weather for a game of catch..." At the end of the No Mercy route, Sans echoes the line: "it's a beautiful day outside. birds are singing, flowers are blooming. on days like these, kids like you... Should be burning in hell."
  • During a No Mercy Run, Papyrus will try to change your ways, telling you "EVERYONE CAN BE A GREAT PERSON IF THEY TRY!" Later, Sans says, "do you think even the worst person can change...? that everyone can be a good person, if they just try? heh heh heh heh..."
• Irony: A game that is heavily critical of replaying it makes it, by far, one of the most replayable games ever. One might ask, "What if I spare this boss?" "What if I spare that boss?" "What if I do a No Mercy run after a Pacifist run?" "What if I do two No Mercy runs?" "What if I do two pacifist runs?" etc, etc. Though, given the game's overall message, this could be completely intentional by making you choose: honor Flowey's last request to let the happy ending be? Or reset everything to scratch the itch?
• I Surrender, Suckers:
  • A particularly cruel way of dispatching Toriel. In her final moments, she lets out a desperate laugh and says you're going to fit in with the monsters outside just fine.
  • Attacking a monster who doesn't want to keep fighting will always do massive amounts of damage; however, depending on if you're doing a neutral or a full No Mercy run, it may be more or less effective than just killing the monster outright on the first turn. Papyrus will always spare you at most one turn before you deplete his HP, so there's no way to kill him without invoking this trope.
  • The surprise final boss of the No Mercy run offers you reconciliation. If you do accept, prepare to get dunked on.
• It Amused Me: During the battle at the end of the genocide route, this is brought up as a possible motivation for your actions, and it may not be entirely wrong. You are, after all, playing a video game to entertain yourself and be happy, right? The boss then brushes the idea off, though, telling you "but that's ridiculous, right? yeah, you're the type of person who won't EVER be happy."
• It Gets Easier: This is the true meaning of LOVE, AKA "Level Of Violence". The more you kill, the easier it is to distance yourself and inflict pain, and the less your own soul hurts when fighting, which is represented by increased HP.

Trope J

• Joke Ending: If you kill only the four main bosses (Toriel, Papyrus, Undyne, and Mettaton) and spare all regular monsters, Sans will call to say a small white dog^note referencing Toby Fox's Author Avatar took over the Underground in the King's absence, and despite him doing nothing but sleeping, this is the best life for everyone.
• Joke Item: The real knife and locket, obtained at New Home near the end of the Genocide Route. They have the highest stats out of any equipment in the game at 99 ATK and 99 DEF respectively... except by the time you get them, the only fight left in the game is Sans, who ignores your DEF and dodges all of your attacks, rendering any armor or weapon completely pointless. That being said, using cheats to put them in your inventory at the beginning of the game instead turns them both into a Game-Breaker, with the locket making you pretty much invincible, and the knife capable of shredding through Undyne the Undying in 3-4 turns.
• Jump Scare:
  • In the No Mercy path, during the ending, if the player chooses not to erase the world, the Fallen Child suddenly lunges toward the screen with a Nightmare Face and a horrific noise playing as the previously black background suddenly begins flashing red. The one solace is that your dialogue cursor does not default to "DO NOT".
  • In the Pacifist path credits, the shot of Mt. Ebott is suddenly replaced by Asriel's powered-up form asking you if you thought it was really over. Subverted, as he then reverts to his non-powered "child" form (with a sheepish grin on his face) and he just wanted to tell you that you still need to watch the backer credits.
  • If you do a Pacifist run after a Genocide run, everything goes great until Toriel walks out of Frisk's room, at which point Frisk opens their eyes and reveals themself to still be Chara with a nightmarish smile and a creepier version of Flowey’s laugh. Unless you choose not to stay with Toriel. Then, you get the usual photo of everyone together… except Frisk has been replaced by Chara, and all of the other faces have been crossed out.
• Just Friends:
  • How Papyrus ends your date, because he feels that there is no way for him to match your infatuation for him. The whole scene is played for laughs and is a parody of Dating Sims. The date with Alphys ends this way as well, since she only went out with you because she mistook Undyne's love letter as yours.
  • Subverted when Asgore asks Toriel if they can be this in the Golden Ending. She responds with a blunt "no," though Alphys hopes they will reconcile.
• "Just Joking" Justification:
  • Royal Guard 01 tries this after he confesses to 02, when it briefly looks like the latter doesn't reciprocate.
  • After Sans implies that he would have killed you the moment you entered Snowdin had he not made a promise to Toriel, he tries to break the ensuing tension by telling you he was just joking (in reality, his threat was meant to show that without his protection, you would have died several times during your journey, such as when he distracts Undyne on the bridge).
  • If you tell Bratty and Catty that you are a human after the completion of the pacifist route, Bratty will try to cover up their previous excitement for the destruction of humanity by saying that they were "just, like, joking, you know?"

Trope K

• Karma Meter: It is revealed near the end of the game that EXP actually stands for "Execution Points", and LOVE stands for "Level Of Violence". These stats essentially act as the game's Meter.
• Kent Brockman News: Mettaton runs a sketch like this, featuring you.
• Killed Mid-Sentence: While mocking the player for falling for one of his tricks, Sans gets pretty much sliced in half and fatally wounded. Everything he knows about the game's mechanics doesn't help him; since this is basically cheating the battle system by having the character attack twice during their turn, he does not see it coming.
  Sans: heh, didja really think you would be able to—
• Killing Intent: The player's during a No Mercy run is so strong that Doggo is able to detect it even though they're standing still. It's actually a plot point, especially in No Mercy. As the player kills more and more monsters, their intent to kill grows stronger, as represented by EXP and LOVE, and monsters are particularly vulnerable to high levels of it. This is why having high LOVE makes the player stronger in combat, and why so many bosses in a No Mercy run fall in a single hit.
• Kill on Sight: Asgore declared that any humans who appeared in the Underground are to be killed following the death of his son at human hands. He regrets the decree immediately once he calms down, but by that point, it's too late to rescind the order without driving his subjects to despair.
• Kleptomaniac Hero Found Underwear: You can search Toriel's clothes drawers at the start of the game, prompting the message "Scandalous! It's Toriel's sock drawer," parodying this trope. Sans's dirty sock pile in his room gets a similar reaction.
• Klingons Love Shakespeare: Because of all the stuff that flows down from the surface world, monster culture has absorbed a lot from human culture, to the point where it's pretty much impossible to say where one stops and the other begins. Most notably, Toriel has a brand-name chocolate bar in her fridge, and both Alphys and Undyne are very dedicated anime fans.
• Know When to Fold 'Em:
  • The best way to win the fight with Undyne is to flee from her, at multiple points when you get the opportunity to flee, and make your way towards Hotland.
  • Undyne herself seems to fall into this if you do the above. After you give her water, she just gets up and walks away instead of chasing you further, likely because she would overheat again.
  • In the fight with Asgore, you have to beat him to a near pulp to win because he destroys the Mercy button. Once that happens, he confesses that he did wrong in restarting the war against humans, because it cost him his wife and he never got his son back. Then he tells you to take his soul and cross the barrier.

Trope L

• Last-Second Chance:
  • The game offers you a meta one during the final cutscene of No Mercy, if you're observant — after the Fallen Child takes control and murders Asgore without your input, they'll turn on Flowey. When he reverts to Asriel's face and voice and begs not to be killed, the Fallen Child falters, and you have to push the button to make them kill their adoptive brother. Alternatively, you can hold ESC, quit the game, and Set Right What Once Went Wrong, but if you got that far without giving up, you probably won't do it now.
  • However, there is one final last chance after this scene. When the Fallen Child gives you the option to either ERASE the world or DO NOT, choose neither, but instead close the game manually like any window or use the Task-Manager, as the ESC or Q buttons may not work. Most of the time, though, people will fall victim into choosing DO NOT.
  • Also, this is invoked by Sans when he gives you a last chance to choose mercy during the fight with him… then kills you if you take it. From a certain perspective, it's not even a subversion, since he specifically points out that your only option at this point to avoid a bad ending is to quit this playthrough entirely.
• Last-Second Ending Choice:
  • If you've been sticking to the No Mercy route since the beginning of the game, Mettaton NEO will be your last boss fight where you can choose to ditch your No Mercy run by not killing enough monsters in Hotland. If you decide to kill them, then you're stuck on the No Mercy route for good.
  • At the very end of the Genocide route, the first Fallen Human seems to offer you this. They'll kill you either way, either by taking your soul after you offer it to them or by destroying the entire world around you.
• Last-Second Word Swap:
  • At the beginning of the game, if you keep avoiding Flowey's "friendliness pellets", he'll grow frustrated, telling you to "RUN. INTO. THE. BULLETS." – before quickly changing the text to say "friendliness pellets" instead.
  • Undyne does this in one of her phone calls.
    Undyne: If it wasn't for that grass, I'd have kicked your...
    Undyne: Uh, if not for that grooty, I'd have kicked your booty.
    Undyne: Don't ask me what a grooty is!!!
• Lawyer-Friendly Cameo: A version of the famous Trollface (which is, in fact, copyrighted by its creator) makes a cameo at the end of Photoshop Flowey's battle, being displayed on the TV screen. It's just barely distinctive enough from the original.
• Lazy Artist:
  • Parodied. Alphys's bed folds up into a "conveniently easy-to-draw cube". Also, Sans's various stands use the same sprite of a snow-covered hut even in the middle of a volcano (which is lampshaded by a nearby NPC); this is Leaning on the Fourth Wall, considering that Sans himself is incredibly lazy.
  • Taken even further when you realize that Sans's sprites themselves never change, they just have details added to them. Even during the fight with him, all that changes are his eyes and his arm. (Until the sweat appears on his forehead.)
  • All of the CORE enemies have a generic out-of-battle sprite that doesn't resemble any of them. Lampshaded in the epilogue when Madjick comments that it looks like a "black sausage" from this angle.
  • There are five video tapes you can "watch" near the end of the game. All of them either take place in total darkness, or the lens cap is still on.
• Leaning on the Fourth Wall:
  • Less leaning, more like actively pressing into it. The game has a meta-story component to it that is very scathing (yet can also be very optimistic and proud) towards the nature of videogame players that are aloof 100% completionists, karma systems in videogames, and the nature of violence in the medium.
  • In a more straightforward example, if you buy enough hot dogs from Sans, he'll note that you must have some kind of thing for hot animals. He's not judging, though; it helps him stay in business!
  • In a No Mercy Run, Gerson taunts you if you try to ask him to FIGHT. He knows you can't do anything to shopkeepers while they're on the screen, so he'll be happy to babble on to you, if it gives other monsters the chance to escape.
  • When you collect and equip the Real Knife, an item that got its name from a rumor about the 2013 demo, the descriptions for it read "Here we are!" and "About time". The Fallen Child seems pretty thankful for your assistance.
  • Flowey takes a shot at the fifth wall in a No Mercy Run, mocking people who want to see it but can't bear to do it themselves in a way that sounds aimed straight at Let's Play viewers.
  • Mettaton has a similar line during his quiz if you say that Alphys has a crush on you; what he says about her watching you on your journey sounds like he's describing people watching a livestream.
  • In the Nintendo Switch version, a secret room can only be entered by opening cyan and red doors via pressing the Joy-Cons' analog sticks a certain way (cyan and red being the colors most commonly associated with the left and right Joy-Cons respectively). This continues in the battle with Mad Mew Mew, where the SOUL is split into cyan and red halves, both of which are controlled by their respective Joy-Cons.
• "Leave Your Quest" Test: Toriel wants you to stay with her at home. She genuinely means well by it, though.
• Leitmotif:
  • The leitmotif that appears in "Once Upon a Time" appears to be the main leitmotif of the game. It appears in "Undertale", "Home", "Can You Really Call this a Hotel, I didn't Receive a Mint on my Pillow or Anything", "Hotel", "Hopes and Dreams", "SAVE the World", “Reunited”, "Bring it in, Guys", and "Last Goodbye". It's often believed that this leitmotif is associated with either the first Fallen Child or Frisk.
  • "Memory" appears in "Undertale", "Finale", and "His Theme". It is associated with Asriel Dreemurr.
  • "Your Best Friend" appears in "Your Best Nightmare", "Finale", "Hopes and Dreams", and "SAVE the World". It is associated with Flowey.
  • Another notable one is the Ruins theme. It doubles as the theme for Waterfall, and plays during both of Undyne's battle themes (Spear of Justice and Battle Against a True Hero). It seems to be the theme of monsters, as a whole.
  • Undyne the Undying and Mettaton NEO's boss themes have extremely similar melodies; there are a few potential reasons for this, including it being the standard 'Genocide' boss theme or it being the First Fallen Human's own fight theme.
  • Snowy is reused in chilling and disturbing effect later on when fighting the Amalgamate that is the amalgamation of Snowdrake's mother and several other monsters.
  • It's implied within the game files that "Determination", the Game Over theme, is meant to be Asgore's theme alongside "Bergentrückung" and "ASGORE".
  • Finally, a particularly devastating one appears in "Hopes and Dreams", which is shared with "Snowdin Town", "Shop", "Dating Start!", and "Dating Fight!" The motif appears in the most lighthearted, welcoming, and, to JRPG fans, most expected parts of the game — in a populated town, in a shop, and while interacting with well-respected NPCs. So when the melody shows up in "Hopes and Dreams", during the final battle in the True Pacifist run, in which the villain has absorbed everyone that contributed to those earlier warm and fuzzy feelings and is using all of those characters' powers to boost his own strength, the emotional impact hits hard as the player realizes both the strength they're up against, and whom they are fighting for.
• Lethal Joke Item: The Instant Noodles. When you first use them in battle, they take a full minute to prepare, and they only heal 4 HP. However, if you use them out of battle, they heal 15 HP, which is pretty decent for a Pacifist Run where you'll only ever have a max of 20 HP. And if you're in "Serious Mode" (certain boss fights in Pacifist and Neutral runs and all the time in a Genocide run) and you use them in battle, you'll just eat them dry and heal a whopping 90 HP, which can be a lifesaver against the final boss of a Genocide run.
  • If you keep the Bandage on, you'll have no additional defense whatsoever, but you'll be guaranteed to be able to run from any encounter that gives you the option.
  • The Punch Card crosses this with a Game-Breaking Bug. Normally, it's an item that has no use other than getting extra Nice Cream, despite the method still being worse than simply getting the Nice Creams earlier in Snowdin, with comedically desperate text on the card itself to boot. However, using it in battle with the Tough Glove equipped dramatically increases the protagonist's attack during the battle, scaling especially well at low levels. And that's before the Punch Card exploit where, due to the manner in which the punch card activates, the player can regain movement when ordinarily they would not have it, which, among other things, allows the user to wrong warp during room transitions, skip cutscenes (including nearly everything in Hotland), and fly out of bounds using vents. Even more broken on the 1.001 patch on Linux specifically, as the player can also interact with objects twice at the same time. It's quite astonishing how such an unassuming item manages to break the game in two.
• Lethal Lava Land: Hotland, the last major region of the Underground, is dry, volcanic, and has many fire-based enemies. It also has some Eternal Engine elements, given that Mettaton has reign over it.
• Letting the Air out of the Band:
  • The music in the tutorial peters out if you choose to consistently avoid Flowey's friendliness pellets to his increasing agitation.
  • This happens to "Your Best Nightmare" in Flowey's battle during the SOUL attacks, after you "call for help" via the Act button and before the bullets are replaced with healing items.
  • While roleplaying, Alphys goes overboard and declares her love for Undyne at the top of her lungs while Alphys' theme plays at a much faster tempo and pitch. When Undyne hears her and comes over, the music slows and dies down as Alphys realizes what she did.
• Level Drain: Downplayed by Napstablook. "Killing" them loses you one experience point. But it's actually a subversion – you lose one experience point, not one EXP (Execution Point).
• Literal Metaphor:
  • When Undyne says, "There are plenty of fish in the sea" to Asgore, Alphys takes it literally, since she's had a crush on Undyne and Asgore.
    Alphys: S-sometimes you've just got to, uh... S-stop going after furry boss monsters and, uh... J-just get to know a really cute fish...? ... It's a metaphor.
  • Ends up as a Brick Joke since a character at Grillby's makes a similar analogy way earlier, only to explain that he indeed threw out a fishing line and wants to make out with an actual fish. When going back in the playable epilogue, he will even mention that he couldn't catch anything, and that isn't a good method to get girls after all.
• Literal-Minded: A fishlike NPC in Grillby's tells you he "put out a line" for some girls and is taking the "plenty of fish in the sea" phrase literally. The fishing pole can be found north of the ice room with the save point, and there's a note with a phone number at the end of the line as bait.
• A Lizard Named "Liz":
  • When Asriel came back to life, he named himself (a sentient golden flower) FLOWEY. It seems Asgore’s Giver of Lame Names trait runs in the family…
  • In an alleyway next to MTT Resort, you can find a shop, in which one of the shopkeepers is an antromorphic cat named Catty.
  • Tsunderplane is a tsundere plane.
  • Pyrope. Pyro is a root that means “fire.” In other words, Pyrope is a fire rope.
  • There is an NPC in Snowdin Town who throws ice into a river. In the Playable Epilogue, when he finally leaves his post, he calls himself “Ice Wolf.”
  • A fire monster in Hotland is named “Heats Flamesman.”
  • In the Ruins, there are frog monsters called Froggits and carrot monsters called Vegetoids.
  • All members of the Snowdin Canine Unit are named some varient of 'dog'.
• Look, a Distraction!:
  • In a Pacifist Run, you get Mettaton to turn around using this so you can flip the switch on his backside. Unfortunately, this switch, instead of shutting Mettaton down, actually activates his Mettaton EX form, which starts the real boss fight. Should you die the first time against Mettaton, you can use this right at the beginning of the fight to skip his monologue and the initial battle and skip right to fighting Mettaton EX.
  • This also comes into play in a No Mercy Run, where you try to trick Monster Kid into turning around so you can get right into the fight with them and kill them before Undyne shows up. It doesn't work, and you still have to fight Undyne the Undying.
• Loophole Abuse: A meta-example: if you quit a No Mercy run by pressing ESC right before the Fallen Child kills Flowey and reset, you avoid the corrupted ending that comes from completing it. Flowey is an Ungrateful Bastard about it the next time you see him.
• Losing Horns: Sans plays a trombone to mock Papyrus when the Annoying Dog steals from Papyrus's bone collection. Lampshaded by Papyrus.
  Papyrus: SANS! STOP PLAGUING MY LIFE WITH INCIDENTAL MUSIC!!!
• Love Doodles: During Mettaton's quiz, if you pick Undyne as Alphys' crush, Mettaton recounts various Undyne-related things Alphys does, such as writing her name in the margins of her notes.
• Love Letter Lunacy: In a Pacifist run, the letter you give to Alphys on Undyne's behalf is unsigned, and Alphys assumes that since you delivered it, you're the one who wrote it.
• Luminescent Blush:
  • Mettaton's quiz show in Hotland is done in the battle system, so the monsters appear in black and white. But when he asks who Alphys' crush is, if you answer Undyne or Asgore, she blushes red in the battle system.
  • This is also present on the Tsunderplane enemy, getting close (but not too close), which translates as hitting a green outline on its attack, making it blush more and more and eventually making it spare-able.
  • Papyrus also blushes a lot when the player is on a date with him and later when Toriel recognizes him.
• Luxury Prison Suite: Parodied when Papyrus captures the player a second time. He claims that this time, the prison will be so nice that the player won't want to leave. The prison is the exact same... except for a hot dog cut up in the food bowl.

Trope M

• Made from Real Girl Scouts: Several times throughout the game, there are references to the spider bake sale. It seems innocuous enough. You put money in a web and spiders bring you a spider donut or some spider cider. However, one sign, encountered early on, makes it a little more unsettling — "Come eat food made by spiders, for spiders, of spiders." Buying the cider and reading its description tells you that it is "Made with whole spiders, not just the juice."
• Made of Magic: Monsters are described as having bodies made mostly of magic, as opposed to humans' bodies being mostly water.
• Magic Countdown: During the bomb defusing segment of the game, you're given 2 minutes to defuse all the bombs. The last 10 seconds are noticeably slower than the first 110. This is an indication that the segment is something of a Worked Shoot.
• Marathon Boss:
  • Most major bosses are this in a Pacifist run. ACT alone won't make them tame and you'll have to repeatedly spare them and just weather their attacks until they choose to stop attacking you or a third party intervenes.
  • If the player goes on the No Mercy route, most enemies go down in a hit or two, except Undyne the Undying and Sans. The battle with the latter lasts 25 turns, more if the player doesn't attack Sans every turn, since attacking him is the only way to progress.
• Mass "Oh, Crap!":
  • All of the Underground during a Genocide Run, to the point that Alphys takes all the survivors into hiding.
  • The boss monsters when Flowey catches them in the Golden Ending and again, all the monsters of the Underground when Flowey absorbs their SOULs.
• Maybe Ever After: In the True ending, Toriel and Asgore are shown to have at least reached enough of an understanding to work together at the school Toriel opens. It's not explicitly stated (and unlikely unless Toriel forgave him) that they got back together, but who knows?
• Meaningful Background Event: Inspecting some areas and background objects, even as early as the first area outside the Ruins, reveals a security camera inside. It's Alphys observing you.
• Meaningful Echo:
  • If Toriel is not killed in her battle to keep the player inside the Ruins, she can be found at the very beginning of the game. In the Playable Epilogue, her son, Asriel, is found here instead. Both of them have the exact same thing to say.
    Toriel/Asriel: Do not worry about me. Someone has to take care of these flowers.
  • One of Asriel's last lines in the epilogue, before wishing you farewell.
    Asriel: Don't kill, and don't be killed, alright?
  • When Toriel first meets you, she saves you from Flowey. In the True Pacifist ending, she stops Asgore and you from fighting in a similar fashion.
  • Several parts of the No Mercy route encounter with Papyrus are echoed by the one with Sans. For instance, Papyrus tells the player that he believes anyone can be great if they try; at the end of the route, Sans paraphrases this as an Armor-Piercing Question, asking the player if they believe it. Additionally, throughout both conversations, the player keeps walking towards them without saying anything, while Papyrus and then Sans attempt to talk them down. And like Papyrus, Sans eventually offers to spare you — though by that point, he is not going to let you live if you accept.
• Meaningful Name:
  • Asriel Dreemurr. The obvious conclusion is that Dreemurr is an anagram of 'murderer', but Azrael is the angel of death and renewal in the Bible, fitting quite well with Asriel's full-powered persona as "The Absolute God of Hyperdeath" (meaning, perpetual death and instant renewal).
  • Frisk. A "Frisk" is an event where you have a good time, something with lots of fun, which reflects the pacifist route. To "Frisk" is also to search a person or object for something concealed, which accurately describes how they go through the Pacifist route, figuring out their opponents' inner struggles and helping them find peace. In Scandinavian languages, to be "Frisk" also means to be "healthy" or "sound".
  • Papyrus' speech is written in Papyrus font. As an overused decorative font, Papyrus is associated with looking silly whilst trying to look cool, which fits his personality perfectly.
  • Sans has a very comical personality, and his speech is written in Comic Sans. He's also very lazy, and Comic Sans is often seen as a lazy choice.
  • An undine is a female water spirit. Undyne is a Fish Person that can conjure spears made from water. Also comes up in the Genocide Route — Undyne the Undying. An undine's goal is to obtain an immortal soul, and Undyne's goal is to obtain the player's SOUL.
  • True to his occupation, Mettaton is very much aware of genre expectations and the fourth wall as it exists in the game. A ton a' meta, in other words. His name could also be a reference to Metatron, an angel whose name abbreviates to MTT and who was a human before being transformed into an archangel.
  • Asgore Dreemurr, which is pronounced Dreamer. He's known for his dream of saving the monsters underground more than his person. As Dreemurr can be rearranged into "Murderer", "Asgore" can be rearranged into "Sage or", making a full anagram of "Sage or murderer?"
• Medium Awareness:
  • Everyone in the game seems to display some level of this, all of them without ever quite Breaking the Fourth Wall. They acknowledge that the player is a unique entity, but they always address the Player Character, not the player themself. With one notable exception: after completing a True Pacifist run, upon re-opening the game, Flowey will appear, saying that there is one last threat to everyone's happiness: you, the player. He pleads with the player to not reset and "let Frisk live their life," specifically differentiating between the Player Character and the player.
  • In a more lighthearted fashion, using CHECK on some enemies will net amusing responses from them regarding what was just said, even though checking produces dialogue that only you can hear.
    Checking Napstablook: This monster doesn't seem to have a sense of humor...
    Napstablook: oh, i'm REAL funny.
• Mercy Invincibility:
  • After you get hit by an enemy's projectile, you'll have a few frames of invincibility. This duration can be increased by specific items.
  • However, the final boss in the No Mercy route does not feature any mercy invincibility, as you obviously deserve none by that point.
• Mercy Mode: The Temmie armor is ludicrously expensive (likely more money than you'd naturally earn in the whole game, total) to avoid the player buying it instantly and making everything easy, but every time you get a Game Over, the price drops. It's still possible to get it otherwise, but much easier if you've spent 10 or 12 tries on Undyne and don't seem to be making any progress.
• Mercy Rewarded:
  • The outcome of the game, and the dialogue towards the player, is more positive if you do not use lethal force. Ignore this, and the game will repeatedly and mercilessly chastise you.
  • You can't gain EXP by sparing enemies. You need to kill them if you want to increase your LV. (In the demo, you can spare injured monsters for EXP; this ability was removed in the full release, however, as it contradicts certain reveals late in the story.)
  • Particularly, a Pacifist Run will not only net you a more positive ending, but also reward you with bonus dialog on the credits screen.
• Mid-Suicide Regret: Near the end of the Genocide Route, Flowey reveals that he attempted to kill himself out of grief towards his situation as a soulless, loveless being (thanks to being the deceased prince Asriel's essence injected into a being without a SOUL). However, as he lay dying, he panicked over what would happen if someone without a SOUL died, and ended up respawning at the royal garden like nothing ever happened, allowing him to discover and exploit Save Scumming.
• Minimalistic Cover Art: The box of the console versions of Undertale show the game's logo against a black background with the city of New Home below.
• Mirroring Factions: The opening intro leads you to believe that monsters and humans are totally different and the monsters are painted as the evil ones. Should you spare monsters and talk to various NPCs, you can see that they aren't really that much different from humans in terms of what they celebrate, what their favorite hobbies are, and so on, but very few characters actually mention the similarities. Should you get the Golden Ending, the trope is further expanded upon where humans and monsters are able to coexist with each other peacefully and very easily since they're very much alike.
• Missing Secret:
  • During the Playable Epilogue during the Golden Ending, the main menu screen, which had been filling up with the characters you befriend over the course of the game, now has a lineup of all of them. There used to be a noticeable gap between Asgore and Monster Kid, with no way to get anyone else to join the lineup. However, as of the January 2016 patch, the gap is no longer there.
  • In Waterfall, during one of the sections where the Monster Kid accompanies you, there's an Echo Flower on a patch of land that seems like a Disconnected Side Area that requires an out-of-the-way detour, but in reality is just plain unreachable. If you use a cheat tool to get to that flower, it'll just say "Error!" like all of the other unreachable Echo Flowers.
• Modular Epilogue: The base ending's epilogue changes depending on who is alive.
• Money for Nothing:
  • Money's usefulness is heavily dependent on which route you're going for: On a Pacifist run, it's borderline useless, since the cheapest healing items heal more or less your entire health bar (especially the Bicicles from Snowdin, which are also double use). On a Neutral run, you might have more use for the high end healing items you can get in Hotland because of your increased health pool, but with high LV comes a lot of defense and battles end sooner, so you're less likely to need them to start with. On a No Mercy run, it seems irrelevant since everyone's too terrified of you to do business, and even Temmie seems smart enough to instead try to scam you with useless stuff. At the end of the No Mercy run, however, money is vital, because Sans will quickly tear through you if you don't have food to help out. This may mean spending a lot of money on the expensive foods at Burgerpants' shop, even if you saved some of the better, limited ones like Toriel's pie and the Instant Noodles.
  • From a technical standpoint, it's played completely straight. You can get infinite money halfway through the game, and the method to do so isn't very subtle (though it's pretty tedious — repeatedly filling your inventory with Dog Residue, and selling it to Temmie). In fact, exploiting it is the only feasible way to get the best armor in the game without dying several times.
• Mood Whiplash:
  • The first encounter with Flowey goes from sickeningly cutesy to absolutely terrifying in the span of a few seconds; how soon in those seconds depend on whether or not you decide to eat his bullets friendliness pellets.
  • The ending to the intro stage is also much darker than the silly, tongue-in-cheek atmosphere of the rest of the game up to that point.
  • After Snowdin, a hilarious area full of just as funny characters, the next area you proceed to is Waterfall, a dark cave lit up by false stars, with flowers that echo back conversations of wishes to see the surface. The music is much more subdued and carries an air of tragedy as you learn just how awful and one-sided the mythical war really was, and all the while, Undyne is pursuing you as a hulking juggernaut who only wants to see you dead. This is the first point where the game makes it clear it has a backstory that goes deeper than just "kid falls down a hole and tries to get out".
  • The process of becoming friends with everyone is mostly made of funny, over the top Dating Sim parodies. Then you descend into Alphys's true lab, which is something straight out of a horror game.
  • Amid the horror of the Amalgamates and how they came to be, you can encounter the creepy-looking Endogeny… and it acts like a big, weird gelatinous dog. The unsettling Woofenstein plays during the fight, which is essentially just a rhythmic, hollow barking sound that slowly speeds up. After you appease it by playing fetch and petting it, it plays a modified Dogsong, one of the goofiest, most light-hearted songs in the game. A jarring shift of tone considering the rest of the place, but a much-needed one to keep it from being too heavy.
  • Sans gets this treatment a few times, adding to his sudden creepiness. The most notable is in the Pacifist run when you are at a restaurant with him, and he tells you that if it hadn't been for Toriel, you would've been dead on the spot once you left the Ruins.
  • On No Mercy, if you fall for Sans' fake spare, he'll insta-kill you and tell you to "geeettttttt dunked on!!!"... then tell you afterwards that if you're really friends, you "won't come back." All while a sped-up version of "Dogsong" plays during the game over screen.
  • If you replay the game on Hard Mode, right after the fight with Toriel, it gets stopped after the battle and the Annoying Dog shows up, saying that's where Hard Mode ends. Toriel then casually brushes off death to bake another pie, as if the whole fight never happened.
    Toriel: You are ending it NOW? And on such a dramatic moment...?
• Mook Chivalry: Zig-Zagged; Monsters can and will combine their bullet patterns on you if you encounter more than one at a time, but each component of the attack will be less intense than what they'd normally be to keep things fair for the player. Most of the Underground's denizens aren't even intentionally trying to attack you, as their bullet patterns are established as their way of expressing themselves. In the final battle of a Genocide run, Sans (who REFUSES to play by these "rules") dodges your attack by casually sidestepping it. He asks if the player thought that he was "going to just stand there and take it", implying that practically everyone else in the game let themselves get hit by you either because of this trope or simply that common sense was not-so-common among monsterkind.
• Moral Myopia: To a degree; the ultimate goal of the monsters is to break out of the Underground, and thanks to the power of human SOULs, killing you is the easiest way of accomplishing that. This leads to some moral issues when you consider that using force to stop them from doing this will get you criticized, even if you were in danger of being killed yourself, and you are always accused of doing this out of annoyance rather than self-defense, regardless of the player's motivations for doing so. However, the number of monsters that attack you intentionally is rather low, and those that do are shown to be conflicted about it, as seen with Undyne (who tries to look for a better reason to kill you before her fight) and Mettaton (who is concerned Asgore will wipe out humanity if he gets a hold of your SOUL). The game seems to be a test of the player's patience, as Flowey mocks during a Pacifist Run, since he suggests that you might kill out of boredom or frustration after dying multiple times.
• More than Mind Control: Implied to be the case with your friends when fighting the final boss of the true pacifist run, Asriel. The Lost Souls refer back to their motivations and negative emotions from earlier in the game; reminding them that Frisk cares for them helps them to break free.
• Morton's Fork:
  • Finish a Genocide Run, and Chara will show up and offer you a chance to destroy the universe. Regardless of your answer, they kill you and do it anyway, crashing the game.
  • On a normal or non-true Pacifist run, the game makes a great deal about what you decide to do with Asgore; multiple characters discuss the dilemma you will face, and the music that plays when you finally make the decision is even called "The Choice." Yet it's actually the one time in the entire game where your decision whether to kill or spare someone makes no difference - if you spare him, Asgore is immediately killed by Flowey, with the game and ending proceeding the same either way.
• Muggle in Mage Custody: The protagonist, who is an ordinary human child, is adopted by the female monster Toriel from the Ruins, who is magical like all the monsters, and wants to keep the main character as her foster child forever. For this reason, she tries to use her magic to seal the exit from the Ruins so that he couldn't leave her.
• Multiple Endings: Now has its own page.
• Mundane Made Awesome:
  • Should you choose to do it (and you need to do it to complete the True Pacifist run), the date with Papyrus plays out like a minigame within the encounter screen, complete with a fancy HUD. Choosing the right answers will cause Papyrus to be visibly shocked and your "date power" to increase (represented by a bar), all the while dramatic music plays as you date him. Do it correctly, and the "date power" bar overflows, showing just how great you are at dating.
  • If you ask the bird in Waterfall to carry you over a disproportionately small gap, a short but grand song (called "Bird That Carries You Over A Disproportionately Small Gap") will play as it slowly flies you across.
  • Undyne treats her cooking lessons this way, showing you such tricks of the kitchen trade as pummeling vegetables with your fists and aggressively heating the stove to the point where her house catches on fire — just for the sake of proving your FIERCE PASSION. This is all after Papyrus defenestrates himself from the room to "let the two of you get to know each other." Possibly served with some discourse about ice cream women in the human world terrorizing everybody with energy spears.
  • Played for laughs if you phone Papyrus and Undyne within the area where the latter first talked to you. Papyrus eventually asks Undyne if she wants to practice monologues with him, which she doesn't. This trope comes in when you phone them again.
    Papyrus: ATTENTION EVERYONE! I AM GOING TO OPEN THE FRIDGE!
    Undyne: Do you have a monologue for EVERYTHING?
  • The flavour text for the save points tends in this direction:
    Narration: Playfully crinkling through the leaves fills you with determination.
• Murder Is the Best Solution: Flowey seems to think so, and advocates it. In gameplay, however, unless you're majorly overlevelled for the area you're in, most fights take just as long to kill someone as they do to spare them (about three to five turns, depending on the enemy setup), making killing, even in self-defense, unjustified.
• Musical Spoiler:
  • The Mad Dummy uses an uptempo remix of Napstablook's battle music, "Ghost Fight", during their fight. The Dummy is Napstablook's cousin.
  • "Finale", a song used while fighting the final boss of the Neutral route, has a part where "His Theme" is just barely audible. This is a hint toward Flowey's origins as Asriel.
  • "She's Playing Piano", the song that plays while in front of Undyne's house before you date her, is a remix of Alphys' theme, which hints towards their future relationship.
  • "Power of NEO", a remix of "Battle Against A True Hero", is much shorter than the latter song and is only a remix of its introduction. The boss it plays for is faking their strength and the battle against them ends in a single turn.
  • "ASGORE" has motifs from "Heartache" and "Determination", hinting that Asgore has a connection to Toriel and he's the one speaking on the Game Over screen.
  • "Memory" briefly plays after you spare Asgore, right before Flowey murders the latter. Since "Memory" is another version of "His Theme", this is another clue towards Flowey's true identity.
• My God, What Have I Done?:
  • Toriel briefly makes an expression that can be described as this and "Oh, Crap!" if she kills you in her boss fight, especially as she deliberately tries to hold back once you're injured.
  • Asgore declared war on humanity in a fit of rage following the death of his children. By the time he realized what he'd done, his wife left him in disgust over the plan to collect human SOU Ls to break the barrier and it was too late to retract his statement without demoralizing his subjects. He still collected the human souls of the childen who fall into the Underground and is loved by the general public, but isn't happy about it at all.
  • Alphys makes it clear how much she regrets the accidental creation of the Amalgamates and despises herself for doing it, but is also too terrified of what the rest of the kingdom would do if they ever found out about what she'd done. So instead she keeps it a secret, her guilt and self-loathing steadily growing the longer she hides the truth.
• My Rules Are Not Your Rules:
  • Sans can sidestep and attack you between turns, something that no enemy in the game has ever done before, and actually acknowledges being sorely outmatched if playing by the rules, hence bending the rules to deny the player victory. He then tries to stall you out for all eternity by never ending his turn. Your character then breaks the fourth wall and cheats Sans right back, delivering the killing blow by moving the interaction box to the command selection and attacking twice, so they manage to stab Sans.
  • Flowey in his final form knows how to SAVE and abuses this ability to land cheap shots after you dodge. Technically, this is following the same mechanics of the game, of which he has full knowledge, as you do. Where this trope comes into play is in that you're limited to one save file. Photoshop Flowey has access to save states, and no less than six slots, presumably because he has access to six souls. The closest thing to that on your side requires outright cheating, by screwing with your save folder and/or backing up several old saves, which obviously cannot be done in normal gameplay.
• Mythology Gag:
  • The track "Fallen Down" was one of Toby Fox's contributions to I Miss You, an album of tracks made with EarthBound's soundfont back in 2011-2012.
  • MeGaLoVania, which was originally the final boss track for The Halloween Hack, makes a reappearance as the theme for the final boss of the Genocide route. The song also appears in Cognitive Dissonance^note although this was a fan remix and in Homestuck as something of a leitmotif for Vriska Serket. You can only hear the song by playing the game much like Vriska; killing your way through everything to max out your LV and ignoring what NPCs say.
  • Like Dr. Andonuts from Fox's The Halloween Hack, Photoshop Flowey is an abomination that hijacks the game over screen if he happens to kill you. Both of them then laugh at your face endlessly, though whereas Andonuts required a manual reset, Flowey simply shuts the game down instead.
  • After Flowey hijacks the game in the neutral route, the image that appears when the intro says "Long ago, two races ruled over the earth: HUMANS and MONSTERS" is changed to the version that appeared in the kickstarter demo, which had a Loox (aka the one that looks like Mike Wazowski) appear as the monster instead of the rabbit-looking one that shows up normally.
• Myth Prologue: The game opens with the tale of how the war between humans and monsters started, and how the monsters were sealed underground. It then tells the myth of how those who climb Mt. Ebott never return.

Trope N

• Neglected Garden: The tree in front of Toriel's house is dying and surrounded by fallen leaves, and she has a dead-looking potted plant in the foyer. They represent her separation from Asgore, who loves gardening and used to take care of the plants in their home.
• Never Trust a Trailer: Parodied.
  • The initial release trailer has the caption "PROBABLY NOT ACTUAL GAME FOOTAGE?" in a scene where a poorly-made 3D model of Toriel is launched into a pile of blocks while a photorealistic image of Toriel appears in the upper left corner says "my child you are breaking my heart". The PlayStation 4 trailer has the same scene, now captioned "PROBABLY STILL NOT ACTUAL GAME FOOTAGE?"
  • The Nintendo Switch trailer has the Toriel model flying after Mew Mew and shooting explosion-causing lasers from her eyes, while the photorealistic Toriel in the background smiles, has red eyes, and says "my child i shall break your heart". The background has a row of blocks and trees (with one tree having Flowey's face), and the monster truck with the Annoying Dog from the PlayStation trailer drives past. The caption says "TOBY WHERE IS THIS FOOTAGE EVEN COMING FROM??"
• Newbie Immunity: Zig-Zagged. For casual players, when you reach a certain HP, it is impossible to lose to Toriel in her boss battle, the flames that fall from the top of the battle box completely avoid your soul heart. However, there is a point before that where you can intentionally move your soul heart towards the flames that land upon the ground, causing your HP to drop past that trigger, and eventually shatter the soul. As an easter egg, for a split second, Toriel gasps in shock before the screen goes dark and your soul shatters.
• New Game Plus: The game keeps track of the player's activities, which affects their experience during later playthroughs. Even if the player resets after reaching the end, certain things persist from their previous runs. Inverted in that only clearing the True Pacifist ending lets you do a "True Reset", which carries over nothing. Unless you have reached a certain ending…
• New Powers as the Plot Demands: Every time Mettaton seems to have you pinned, either you or Alphys comes up with some new power, like a system to hack or a jetpack upgrade to your phone, that the player has never used or even heard referenced in the whole game prior. This is because Mettaton and Alphys have arranged the whole thing so that Alphys can seem like a hero, giving you just what you need at the moment you need it most.
• New Weird: At first appears to be your standard fantasy RPG, but later it starts introducing Science Fiction elements, Cosmic Horror Story elements, and a handy dose of Postmodernism to boot.
• Nice Job Breaking It, Hero:
  • Right before the final fight in the True Pacifist ending, Flowey tells you it's your fault that he can reach his true form since your making friends with everyone empowered them to gather in one place to help you, allowing Flowey to steal all their souls in one fell swoop.
  • If you're on a No Mercy route, then Toriel helping you is what allows you to reach the rest of the Underground. On a Neutral Route ending where she's alive but Papyrus isn't, Sans doesn't have the heart to tell her that her promise led to Frisk killing his brother.
  • Alphys' experiments involving DETERMINATION led to the creation of Flowey, a being that had the "will to live" but no soul, and therefore no capacity for compassion or love.
  • Alphys assists the player on Neutral runs even if they've murdered enough monsters to drive the survivors into anger and/or despair, potentially allowing the player to kill even more monsters. Depending on the player's actions, Alphys may even be Driven to Suicide by the game's end.
• Nice Mean And In Between:
  • Papyrus, Undyne, and Mettaton, the Arc Villains of Snowdin, Waterfall, and Hotland, respectively. Papyrus is The Pollyanna, and even if you lose to him in battle, will always stop before killing you and instead capture you (which means putting you in an unlocked shed next to his house). Losing to him repeatedly will make him feel bad about fighting you, and allow you to pass by him peacefully — he is also the first character who can be befriended in the game, and you can do so in literally any playthrough as long as you don't kill him. In contrast, Undyne is a Jerk with a Heart of Gold who loathes all humans and hunts you down all over Waterfall in an attempt to kill you and take your soul, and befriending her at all requires having never killed a single monster on that run. Mettaton is a egotistical performer who, though treating you playfully throughout your journey through Hotland, still fully intends to kill you and take your soul, but is doing it to prevent Asgore from using it to destroy all of humanity (and also so that he can become a big-shot star on the surface).
  • Their respective areas reflect this too: Snowdin, being a snow forest ending on a Christmas village, is a warm and friendly place to show you there are people living their everyday lives in the Underground, Waterfall is a somber and desolate area that shows you why monsters feel claustrophobic underground and why they so badly need your SOUL to escape, and Hotland combines both, with monsters living their everyday lives surrounded by lethal hazards but remaining aggressive because they dream about the surface and are fascinated by humanity.
• Nintendo Hard: Averted for most of the No Mercy run, since the constant killings have made you ridiculously overpowered, except in two cases: Undyne the Undying, a surprisingly difficult boss who emerges after you've already one-shotted Undyne, and Sans, a surprise Marathon Boss who utterly destroys you over and over again, and who you literally stand no chance of beating without cheating the battle system.
• No Body Left Behind: Presumably lampshading the common fantasy roleplaying game trope, monsters literally turn to dust upon death. Unlike in those other games, here it becomes an important plot point. And is eventually curiously averted by Sans, who bleeds when struck and dies off-screen.
• Nobody Poops:
  • Played straight, there are no bathrooms in any house in the game. Monster food is pure energy, and a monster comments on how human food is disgusting because it "passes through your whole body." Possibly implied to soon be averted in the playable epilogue as the same monster mentions about how excited it will be to first try human food and then try a bathroom for the very first time.
  • And Zig-Zagged with the Dog Residue item, which is actually things like "dirty dishes left unwashed by a dog," and "jigsaw puzzle left unfinished by a dog."
• No Fair Cheating: Downplayed. Certain blatantly obvious edits to your save file will cause the game to metaphorically wink at you, but not have any real consequences. For example, if your name is over the character limit◊.
• No Fourth Wall: Game mechanics like saving, loading, experience, and leveling up are integral parts of the game's story and are commonly referred to by name by characters within the narrative. In addition, you, the player, are heavily implied to be an entity that exists outside of the actual game that is able to use a vessel (a.k.a., the Player Character) to interact with the world. You and Frisk are implied to be completely separate characters, with you merely inhabiting Frisk's body through the SOUL in order to determine what happens in the world.
• No-Harm Requirement: Undertale gives players the option to do this on nearly every encounter in the game. It's considerably more difficult, since it turns even a random encounter into a puzzle boss and you don't gain more health since you don't get the necessary EXP from killing enemies. Following through to the end, however, unlocks the game's Golden Ending.
• Non-Action Guy: Most enemies in the early stages aren't aggressive, and some of them are very easy to SPARE. Given Flowey's claims of "kill or be killed", this would appear to be very atypical of the underground. Or so one might think from the demo alone. Monsters on the outside aren't much less docile than the ones inside. Flowey may have simply been trying to make you think otherwise.
• Non-Human Head: Several of the NPCs, including the receptionist at the MTT lobby who has a giant hand for a head, and a few nameless NPCs with black and pink-or-yellow diamond-patterned squares for heads.
• Non-Malicious Monster: Even though they exhibit weird behavior that may harm you, most of the monsters you encounter in battle bear you no ill will.
• Non-Standard Game Over: All of the three final bosses have one.
  • Photoshop Flowey begins the typical game over dialogue in Asgore's voice… only to reveal it's really him, laughing about the nightmare you'll never wake up from. Then he closes the game.
  • The final boss of the No Mercy Route has one if you opt to take up his Mercy offer, after which he traps you in a truly undodgeable insta-kill bone prison and mocks you from beyond the grave with a goofy game over theme and an assertion that, after all that you've done, he'll never be your friend again.
    Sans: geeettttttt dunked on!!!
  • This also happens, combined with Fission Mailed, during the Asriel Dreemurr boss fight; your SOUL cracks... and then fuses back together.
• Noodle Incident: If you call Papyrus and Undyne in the Apron room in Hotland, they'll reminisce about a time they "cooked" popsicles. All they reveal to you is that whatever they did created such a mess that it "took forever to hose everything off".
• No-Sell: Certain enemies, such as the Mad Dummy and Mettaton, are immune to the physical attacks inflicted with the Fight command. They must be defeated through other means. In addition, Sans will step out of the way of your attacks, refusing to just stand there and take them.
• No Sidepaths, No Exploration, No Freedom: Looking from certain high vantage points of Snowdin and New Home implies the Underground is actually enormous, but most of your journey is through relatively small, narrow, and entirely linear paths with the occasional tease of other walkways you can't reach (like the conveyor belts where you find the frying pan, or the echo flower across the rainy path you see Monster Kid look at in Waterfall).
• No Smoking: Most characters are allowed to smoke normally, most prominently with Burgerpants, except in one instance for comic effect: Doggo smokes dog treats in the same way you would smoke a cigarette. You can even find some dog treat "butts" on the ground after you fight him.
• Not Completely Useless: The Apron is an item that lets you restore 1 HP a turn, and considering the typical length of the battles and amount of damage you receive from bosses, it has no real use for the most part. However, during the fight against Asgore (who will always give you a chance to defend yourself before making a finishing blow), it becomes a true lifesaver.
• Not in Front of the Kid:
  • Characters will watch their language around you. Undyne replaces "ass" with "booty" in one phone call. On another occasion, Toriel says "hell", then replaces it with "heck".
  • In a True Pacifist Run, when everyone in the cast meets at the barrier, Undyne and Alphys oblige Mettaton by almost kissing, which is interrupted by Toriel saying, "Not in front of the human!"
• "Not Making This Up" Disclaimer: A sign before a miniboss fight in the second area reads "Warning: Dog Marriage". If you check it again to make sure if you read it correctly, the text confirms that "yes, you read that correctly."
• Not Quite Back to Normal: A True Reset will erase every single event from every characters' memories and the game will be as if it was just installed. However, if the player completes the Genocide route, Chara will take over. A True Reset will never truly remove their presence from the game.
• "Not So Different" Remark: Toriel says this to you if you Back Stab her after she lowers her guard. In the demo, kill her three times and Flowey mockingly says you're like him. Kill all the monsters and he says it more respectfully.
• Not the Fall That Kills You…:
  • You survive your fall into the Underground because a bed of golden flowers breaks your fall. Toriel takes care of the flowers for this reason (among others). The first Fallen Child got injured when they fell, because the flowers hadn't even been planted yet.
  • They also cushion you when the Waterfall current sweeps you away from the second encounter with Undyne.
• Number of the Beast:
  • An extremely well-hidden example: The piece the player is judged just before the final boss, "The Choice", is actually the last part of "Undertale" stretched out to 666% of the original length.
  • This also shows up all over the place when dealing with W.D. Gaster, who appears to be a relative of Sans's. His stats (though also completely pointless, as Gaster has no actual fight) are all sixes, and all of the 'Fun' values needed to see his followers (and possibly get a glimpse of the man himself) begin with 6, culminating in what may or may not be Gaster himself appearing at 66.

---