Undertale, or UnderTale, is an Indie game that has attracted lots of creeps and bad artists alike. Although the creator of the game Toby Fox usually tries to prevent spoilers, it has become oversaturated to such an outrageous degree that, if you found this page, you definitely know at least a little bit about the tropes and overall plot of UnderTale. The YouTube Poop wiki is not a charity and will not explain to You every little detail about beating the game. Most of the active members at the YouTube Poop Wiki are not fans of UnderTale, but the person who wrote this page is. Ergo, the reader can expect lots of butt-kissing with this article.
The game of UnderTale begins in the year 2715. Anyone who continues to read through this article will find spoilers for real life; however, none of the spoilers will be beneficial, as the YTP Wiki has blanked out the winning lottery tickets.
The game is very interactive in how the player proceeds; however, there can only be one canon neutral route, and the author is going to make it up arbitrarily.
The world of Undertale was originally another planet's afterlife, though the residents still refer to it as Earth. Scientists are still not certain what being created this realm or the exact requirements for being sent there. It should be noted that only some of its residents were sent there upon "death" and that life did evolve there after its creators' disappearance.
This plane of reality has quite a few notable differences. For example, Tycho Brahe's theory that all planets in the solar system (save the Earth) revolve around the Sun, which is moving around the Earth (the center of the universe) has been proven canon in this universe by top scientists. The universe is held together by a strange aura with seemingly aimless goals, though gravity still functions normally on the center planet. The number of stars in this universe is much lower (the exact number would have 20 digits, though scientists are still in a heated debate about it).
The beings at the center are divided into two classes: humans and monsters. Though the monsters had what they called "magic" on their side, the humans had Determination. In its purest form, Determination gives its user the ability to save, load, and reset, though it is broken down into the simpler forms: integrity, perseverance, kindness, patience, bravery, and justice. These names can make common speech very confusing in this world. For example, outside of this plane of reality, someone with determination (probably) doesn't have the ability to time travel.
Note: This is the boring part.
In the year 1993, the humans raged war against the monsters and sealed them underground without a single casualty. It is for this reason, that nobody wants to find more information about this great war. That is, the humans suffered no casualities. The monster population was decimated. In June 1993, just before the war broke out, the human population was 10,000,000. By the war’s end in April 15, 1994, the monster population was a measly 20,000.
The monsters were driven underground, and seven human wizards cast a spell to create the Barrier, which lets things in (mostly garbage) and nothing out. Of course, if someone were to have a human soul and a monster soul, they could cross the barrier with no problem. In fact, any shmuck who happens to be a monster could absorb seven human souls and break the barrier for good.
Regardless of how strong their owner is, monster souls are pussies. They shatter immediately upon the death of the monster, though through the power of bullshit, a boss monster’s soul can survive after death. Based on scientific calculations, it takes 81 monster souls to equal one human soul.
In 2015, a human named Chara fell to the Underground through a hole in Mt. Ebott. Prince Asriel was the first to find the human, and King Asgore and Queen Toriel adopted the human as a fashion statement of some sort, making Asriel and Chara adopted siblings. Chara attempted to assassinate Asgore by feeding him cake made with poisonous flowers. This failure led Chara to her next plan, which was also her biggest blunder. Chara ate an unnecessarily large amount these poisonous flowers on film as part of a publicity stunt on YouTube to gain a following for a purpose they never really got around to figuring out. She died, and Asriel absorbed her soul and flew past the barrier to the Underground to show the human’s dead body (their consciousness was in the soul he absorbed, but whatever gets the job done) the flowers on the surface. The humans cheered for Asriel for killing Chara, who had previously been hated by literally everyone in the village, including Chara’s birth parents who neglected to attend their birth, much like Doofenshmirtz’s parents. Unfortunately due to a fireworks malfunction, Asriel was injured. He made it back home just in time to die in front of his parents, thus igniting Asgore’s rage at the humans (he thought the village attacked his son) and starting the war on humanity. Chara’s soul was destroyed as the same time as Asriel’s. Asriel’s consciousness was transferred to a flower while Chara’s soul was teleported 700 years into the future for absolutely no reason whatsoever.
Once per century, a human child falls into the same hole in Mt. Ebott, but because of the war on humans, they were killed by Asgore’s orders and their souls placed in containers for the purposes of Asgore absorbing seven to shatter the barrier. The souls of Integrity, Patience, and Kindness were killed by soldiers (though only the soul of Integrity actually fought back). The souls of Bravery and Perseverance fought Asgore, but died in the end. The soul of Justice made it to Asgore as well, but committed suicide once Asgore destroyed their “Mercy” button (they were trying to do a True Pacifist Run).
The game really begins in 2715 with the protagonist Frisk falling into the Underground in an attempt of suicide (probably because of depression or maybe anxiety). Upon arriving, Chara’s ghost begins to possess Frisk, which somehow forces Chara to act as a narrator for the game. Frisk meets Flowey the Flower (expect a recurring theme in terrible names). Flowey immediately tries to fuck with Frisk by telling them to run into bullets to collect LV (which Flowey says stands for “love,” but as any person looking at spoilers for UnderTale knows, stands for “level of violence”). Flowey is knocked out of the way by a fireball launched by an alternate universe’s version of Mario whose fireballs always ended up in other universes. Toriel comes by and introduces herself to the player. After Toriel solves the first several puzzles, she tells Frisk she has to go (apparently, there’s a supermarket in the abandoned Ruins) and that they should behave themselves.
Naturally, Frisk leaves the room and begins fighting random enemies. She spares some of them, but kills others for fun, gaining execution points along the way. Eventually, Frisk and Toriel are reunited, but Frisk soon realizes she isn’t going home unless she acts. This results in Toriel trying to destroy the only exit to Snowden (on the way to the exit of the Underground) and Frisk killing her because they’d only been fighting typical enemies that would appear at the beginning of an RPG. Frisk might also have some mental issues.
Having killed the only monster who had showed them kindness as opposed to blood lust, Frisk exits the ruins and heads eastwards in a snowy forest. They soon find that a monster in the shadows has caught up to them. He says they should turn around a greet a new friend by shaking his hand. Upon doing so, Frisk soon finds that it is actually a lazy skeleton who loves bad jokes (and that he had a whoopie cushion in his hand for this occasion). His name is Sans.
Sans explains that his job is to search for humans, but he’s too much of a lazy fuck to capture one. His brother Papyrus, however, has an obsession with capturing a human that can only be rivaled to his crippling addiction to making Spaghetti.
Frisk soon finds themself solving Papyrus’s easily-overcome puzzles. Chara would be annoyed by Frisk’s insistence on keeping up the charade that Papyrus isn’t a loser if they weren’t so upset over Frisk not killing anyone in Snowden (except Jerry because he sucks at everything). The only challenging puzzle was given by Sans. It was the Monster Kids Word Search, which was literally impossible due to a typo in the puzzle’s first line.
Soon enough, Frisk makes it to the town in Snowden and soon after fights Papyrus. Frisk, however, is too much of a weirdo to strike down Papyrus, so they spare him. Papyrus explains that the barrier is farther east in the Capital, and he states that King Asgore Dreemurr is a “big fuzzy pushover” who will gladly step aside so Frisk can cross the barrier (even though he isn’t a pushover at all and Frisk can’t cross the barrier with his soul).
Frisk finds Sans working another job in Waterfall, which leads Sans to take a break at Grillby’s with them. It is implied here that Sans can teleport with no explained limit. It’s also implied that Sans can stop time, but only during this one cutscene. They both eat some fries, but Sans ruins it by unscrewing the ketchup before handing it to the human.
Frisk travels through Waterfall, narrowly avoiding the attacks of Undyne, the head of the Royal Guard. There’s not much to say about this part of the journey because it’s genuinely not as funny as the other areas, though the secret fight with SpongeBob and Patrick was pretty funny.
Frisk (at LV 6) confronts Undyne, killing her. Undyne somehow musters up the ability to fight after her HP reaches zero, but quickly becomes too weak to fight. She finally dies. Frisk is now at LV 8 (actually 2 execution points below LV 9). Frisk decides she's had enough and that she won't kill anyone else on her journey, which greatly annoys Chara.
Hotlands and the COREEdit
Frisk continues into the Hotlands. Upon entering the lab, they met Alphys (a nervous wreck and obsessive anime fan) who explains that, despite their job demanding they help capture the fallen human, they actually grew to root for Frisk (they forgot to Tivo the fight with Undyne). They are interrupted by the killer robot and celebrity of the Underground Mettaton, built by Dr. Alphys herself. After a televised quiz show, Mettaton realizes that Alphys is giving Frisk all the answers, so he asks who Alphys has a crush on—Undyne, Asgore, the Human, or Someone else, though every answer is at least partially correct. Frisk not wanting to answer, Chara chooses "Undyne" as the answer to add salt to the wound (though once again, Alphys doesn't know Undyne is dead).
Frisk continues through Hotlands while dealing with Mettaton's elaborate plans to kill the human, though Alphys seems to always find a way to save the human just in time. At one point, Frisk also found Sans's illegal hot dog stand and demanded 29 free hot dogs in exchange for not telling the cops (which were stacked on their head).
Frisk finds herself stuck in Muffet's spider web after having disagreed with Muffet's price gouging. During this fight, Muffet pours Frisk a cup of spiders, and Chara gains control of Frisk's body and drinks the spiders, much to Muffet's horror (though this somehow doesn't count as gaining execution points). Muffet eventually realizes she fucked up in assuming Frisk liked hurting spiders. She apologizes for it and for assuming Frisk is female (I mean, Frisk was born in a female's body and identifies as female, but there's no reason to just assume their gender).
Frisk eventually makes it to Hotel Mettaton (not to be confused with Hotel Mario) where they meet up with Sans. Sans takes another one of his shortcuts (teleporting), so he won't have to actually pay for a reservation in the restaurant inside. Sans informs Frisk that he entered a romantic relationship with Toriel, which involves telling bad jokes and having sex (though he swears he only heard her voice through the large door between the Ruins and Snowden). He made a promise to Toriel to take care of the next human who fell to the Underground. If it hadn't been for this, Sans would've murdered Frisk immediately for having killed Toriel (this would've gotten Sans thrown in the slammer, but that's not the point). Sans then leaves before the cops can get him arrested for having dinner with the human. Frisk continues through the Core and eventually finds Mettaton despite nothing in the Core resembling Alphys's map.
Mettaton soon delivers an unnecessarily long speech about how he was the one who had been messing with Alphys's inside information the whole (as well as offering Muffet money for a female human in a striped shirt, meaning Mettaton was actually the one who assumed Frisk's gender) because despite going along with the charade that Alphys would always save Frisk and convince them to stay in the Underground, he actually wants to absorb the human's soul, pass through the barrier, and become a star among humans. Upon Alphys's final instructions over their cell phone, Frisk gets Mettaton to turn around so they can flip the switch on his back.
Mettaton, now sporting his "Mettaton EX" form, begins the televised fight with Frisk. However, Frisk causes the ratings to sore so high that they reach the call-in goal. Mettaton takes several calls from all sorts of monsters who are heartbroken to hear Mettaton is leaving the Underground. He decides to stay Underground and remain the only celebrity there, just before his batteries run out (because this form is not even remotely fuel efficient). Frisk walks toward the door, but Alphys finally decides she cannot take this lie anymore and informs Frisk they'll have to brutally murder Asgore and steal his soul (which might include leaving Asgore in purgatory, much the same way Asgore's six human souls are left). Alphys runs away to parts unknown, and Frisk uses the elevator (which runs on Wonka bullshit as it also goes sideways) to travel to the Capital.
Frisk soon arrives at New Home where Asgore lives. The monsters who were rejected from the previous battle (they're so stupid as shit, they think Frisk is a monster) tell Frisk the story of Asriel (though they still insist that the humans directly attacked Asriel due to thinking Asriel had killed an innocent human).
Frisk enters the final corridor where she meets with Sans for the final time (at least in the neutral run). Sans finally tells Frisk that LV stands for Level of Violence, that EXP stands for Execution Points, and that Frisk is a total monster for killing, like, twenty monsters, including innocent little Toriel. Sans leaves Frisk to decide the fate of monsters with Asgore.
Frisk finds King Asgore watering flowers of the same species from 700 years prior. They proceed to the site of the barrier where Frisk and Asgore begin their battle, though Asgore, as always shatters his human opponent's "Mercy" button, leaving Frisk with no choice but to attack Asgore. Upon Asgore's defeat, Frisk offers to spare Asgore (apparently, the mercy button could be repaired the whole time). Unfortunately before Asgore can offer Frisk a cozy life they don't deserve, Flowey kills the king and breaks his soul. Flowey then absorbs the six human souls and become Photoshop Flowey.
Frisk is now in an empty black void, and Photoshop Flowey appears to inform them that their save file is gone forever. Frisk soon enters the battle against the behemoth. Fortunately (or unfortunately since Frisk murdered several innocent monsters), the human souls begin to help Frisk with extra health upon Frisk calling them for help. Photoshop Flowey's defenses quickly drop, and he is defeated, only for him to reload a file where he still has all his health. He then murders Frisk 48 times by reloading to a file in which they are alive. Flowey decides to kill Frisk for good, but the bullets heal Frisk instead. The human souls leave Flowey's body. Flowey is now defeated, but Frisk insists on letting him go (despite having every reason to kill him). Frisk then enters a strange door.
Sans calls, but despite Frisk having crippling OCD and answering the phone no matter the situation, Frisk does not answer. Sans leaves a message, saying they made the snowman from earlier very happy by letting a piece of him join them for the entire adventure. Of course, they also killed several innocent civilians, thus leaving the Underground ripe for Mettaton to conquer as well as causing the human souls to vanish along with all the monsters' hopes and dreams, but the snowman is still happy, and that clearly negates the strong tone of hopelessness that Mettaton, his agent (Sans), and his other agent (Papyrus) try to give off. Frisk, probably dead, decides to reset to the moment they started their journey, but without killing a bunch of innocent monsters (and Jerry).
True Pacifist RouteEdit
Beginning the game again from the beginning, Frisk runs into Flowey who reminds them not to kill anyone this time. Toriel comes to explain the situation about being the first human in the Underground in 100 years. This time, however, Frisk refrains from fighting anyone (or to be more accurate, from using attacks in battles), including Toriel who eventually stops attacking Frisk as they get closer and closer to the finishing blow.
Frisk continues in Snowden where they tolerate the bullshit from Sans and Papyrus (albeit Sans finds it odd that Frisk turned around before he said to, and Papyrus actually recognizes the human immediately instead of thinking that dumb rock was the human). Papyrus is spared again, of course. Sans tries to trick Frisk into ruining their fries with too much ketchup, but Frisk does not ask for ketchup.
Frisk proceeds to Waterfall where they spare Undyne by, running away until she tires out in the Hotlands. Frisk gives Undyne some water that just happened to be nearby.
Papyrus soon formally introduces the human to Undyne and leaves the house. Undyne asks if the human is here to rub in their victory, which the human agrees is true. Undyne decides the best revenge is to make the human become so attached to her as a friend that they start feeling bad about defeating her, though Undyne still finds it odd when the human points at Undyne when asked what she would like to drink. Soon, they make some spaghetti as extreme as they can (rivaling even Poochy in terms of being extreme). Frisk continues turning up the temperature on the spaghetti until the pot becomes red hot then white hot then blue hot (which is a real thing if You would stop masturbating long enough to take a basic astronomy class). Undyne's house completely in flames, Frisk decides to follow Undyne to her new residence (the same house Papyrus and Sans call home).
Once there, Undyne gives Frisk an "important letter" addressed to Dr. Alphys. Chara (in control of Frisk's body) tries to open it right in front of Undyne. The human goes to deliver it, but despite what seems like common sense, Chara throws the letter away. They return to Undyne to apologize, but Undyne confesses that the letter sucked. The first letter had really sloppy handwriting because Undyne was super nervous while writing it. The letter sounded really sappy too. Undyne hands Frisk "Undyne's Letter EX Director's Cut" which is surprisingly well-written and romantic. Chara tried to discard it again, but the letter got the better of them (both Chara and Frisk).
They deliver it to Alphys, but Alphys thinks this letter is from Frisk. Under the impression that this is the universe's way of helping them complete the True Pacifist Run and obtain their perfect happy ending. Frisk continues to the dump in Waterfall where Alphys admits she can't go through with the date because she loves Undyne too much (and also Asgore, but God knows that ain't happnening). Together, they decide to do some role-playing, but instead of Alphys practicing on Frisk in place of Undyne, Frisk roleplays as Dr. Alphys while Alphys roleplays as Undyne. This scenario is one of Frisk's fetishes. Frisk begins hitting on Alphys hard, leading Alphys to say, "Dr. Alphys, what has gotten into you." The severe mind fuck continues until Undyne shows up for her date with Alphys. Frisk finally admits that the letter was from Undyne. This makes Undyne angry, but Alphys finally admits that her research on humans is actually her reading manga and watching anime (which is fictional). Undyne agrees to have Papyrus train Undyne. Papyrus shows up and takes Alphys away on their first training session. Undyne asks Frisk if anime is real and is crushed to hear it isn't. Undyne thanks the human for being kind to Alphys and heads home (which is still on fire) to cry into her pillow for 30 minutes over the anime thing.
Mettaton EX goes through his shit about killing the human to become humanity's top robot celebrity... again... this time, however, once they reach the call-in goal, Frisk leaves before Mettaton can deliver the line about his batteries running out, proclaiming, "Swiggity Swending! I'm comin' for that perfect ending."
Alphys follows Frisk and breaks down again. Frisk follows her this time and finds a letter in Wing Dings (which is illegible in Wing Dings standards which paradoxically makes it readable to Frisk). Frisk sees that the letter says Alphys is going to end it all. Frisk goes into the elevator expecting to find Alphys's dead body (thinking Alphys didn't lie about it being a bathroom). Frisk, however, proceeds downward to the True Lab. She non-violently resists a series of monsters among monsters known as the amalgamates (which roughly translates into English as "sins against nature"). Frisk reads the lab entries by Alphys (and possibly Sans too), learning about the story of how Alphys attempted to inject dying monster patients with determination extracted from the six human souls (as the six traits combine to form True Determination). Unfortunately for her, these bodies start to melt and fuse together, which probably ruined Frisk's perfect ending before her adventure started. Alphys later decided it might be a better idea to inject determination into something neither monster nor human, leading her to believe the flower that always blooms first in Asgore's garden might be a good candidate since it already has a great desire to live.
Frisk also finds some strange video tapes containing the royal family (Asgore and Toriel) as well as a child named Asriel and someone named Chara.
Frisk is cornered by the Amalgamates, but Alphys comes in to inform these monstrosities that it's their feeding time. Alphys explains to Frisk that she "decided not to kill herself because it'd be too much work cleaning up the mess." Frisk begins to leave the lab. However, she finds two more lab entries explaining that Alphys successfully put determination in a flower and that the flower escaped.
Frisk proceeds to the elevator but receives an odd and dramatic phone call from a voice she doesn't recognize. The voice speaks to someone named Chara, that the voice belongs to "your [their] best friend," and that they'll be reunited soon. Frisk, still not aware of the name of the ghost possessing her, decides it was a wrong number despite not hearing the wrong number song. (Frisk got a call from a wrong number earlier on in the True Pacifist run).
Frisk is taken to the Capital immediately where she runs into Sans who delivers a speech to them about doing the right thing and never gaining "LV," despite gaining a different kind of love. Chara decides this speech was dumb and resets to the save point in the last corridor. Sans begins the speech again only to notice that Frisk appears bored (despite Frisk always having the -_- face). Sans figures out Frisk is a low-key time-traveler and gives them instructions to go back to this moment and tell Sans his secret password that only a time-traveler would know. Frisk does so, but Sans asks them to speak up. Frisk finally yells out, "I'm the legendary fart-knocker!" Sans laughs and says this isn't his password and gives them another password. This time, the player goes back and has to yell out, "I'd eat some shit-stained underwear!" Sans laughs again, proclaiming this still isn't the password. This continues until Sans finally gives Frisk the real password: "I'm a dirty, stuck-up, sadistic, shit-eating, cock-sucking, piss-swimming, Nazi-loving, anal-fondling, heartless, mindless, spineless, dickless, testicle-choking, bean sucking, toilet kissing asshole!" This time, Sans is blown away that she knows this password and says to go to his room and find out who he really is. He teleports again, but Frisk realizes the key is already on her keychain.
Frisk returns to the home of Sans and Papyrus and proceeds to his room. Frisk finds a dark empty void with ground made of what seems to be pure darkness. Frisk walks forward, but Papyrus comes in and turns on the lights, remarking that Sans is pranking the human from beyond space and time again. Papyrus hates when he does this. Frisk explores Sans's disgusting room for a hint about his past. Frisk finds another key and heads to the back of their house to access Sans's lab where they find a drawer containing a badge and a photo of Sans with people they don't recognize. They find blue prints written in a strange, foreign language (Wing Dings written legibly this time). She even finds a strange machine under a tent. Frisk finally decides to give up on this quest to figure out who Sans is and just accept their perfect ending.
Frisk begins the fight with Asgore, but Toriel punches Asgore in the face with her literally flaming fist and exclaims "Get dumped on!" which makes Undyne laugh, and the Annoying Dog to exclaim "OOOOOOOH! WHERE YOU AT?!" Feeling bad now, Undyne comforts the king. Sans enters the room to stop the human's fight with Asgore as well to discover the fight is already not happening, which makes him happy since he loves doing absolutely nothing. Alphys tries to intervene as well. Papyrus comes in to do the same. They all exchange anecdotes and laughs. Undyne and Alphys then awkwardly have sex (with Alphys losing her virginity) right in front of the human and their friends. Mettaton EX would've stopped this had he not been filming this to sell as pornography.
Afterwards, Sans asks Papyrus who told everyone to come here to stop the fight. Papyrus says, "Let's just say a talking flower told me." Alphys exclaims "A talking flower!" It was too late. With the six souls in hand, Flowey held Frisk's friends with great vines and nearly kills them with his bullets surrounding Frisk. However, their friends heal Frisk. Flowey says he promises to break the barrier if Frisk can defeat Flowey in his god-like form. More and more people come in to save Frisk, but Flowey absorbs them all. With six human souls and 81 monster souls, Flowey takes on his original form... a child boss monster named Asriel. He then takes on his "Angel of Death" form and begins fighting Frisk.
Frisk's health reaches zero, but Frisk is so full of determination to see her perfect ending that she's become immortal until she reaches her ending. Flowey reaches his "GOD OF HYPER DEATH" form, reading to kill Frisk, erase everyone's memories, just to repeat the story again and again, to continue playing with Chara forever. Frisk, barely being able to fight back even if they wanted to, begins to call for her friends. They restore the memories of everyone starting with Papyrus and Sans. They then restore Toriel's memories, which forces Asgore to remember too. They called for Undyne then Alphys. Finally, they called for Asriel himself. He says he refuses to be "saved" (not to be confused with the other kind of "being saved"), but Frisk's overflowing determination won't let him continue without becoming Frisk's final new friend from the Underground. Asriel tries everything to kill Frisk, finally firing an energy beam that would put Super Saiyan 3 Goku to shame, trying harder and harder to knock off the last 0.00000000001 hit point of Frisk's health bar, but he cannot. Frisk continues calling for Asriel. Asriel finally relents.
After a good hug, Asriel apologizes for everything and acknowledges that Frisk isn't Chara while Chara just sits there and does nothing like the psychopath they are. Frisk forgives Asriel for his psychopathic nearly-complete and -total victory. Asriel destroys the barrier and releases the souls, apparently being too stupid to keep one of the human souls to avoid becoming a literally soulless psychopath again.
Frisk wakes up in the room just before the barrier with all their friends who remember nothing of the encounter with Asriel, the angel of the prophecy. They continue exchanging funny stories, and Toriel even says "Who the fuck is Sans?" and becomes embarrassed. Frisk backtracks to meet with all her new friends (including the amalgamates, which got a happy ending in a very "technical" sense). They even speak with Asriel one last time. He tells Frisk he can't go back and that they should never reveal Flowey's true identity to anyone. He inquires about why Frisk came to Mt. Ebott in the first place, but declares the subject too sad for him to handle. Frisk leaves and finishes the story. The monsters and Frisk look out at the sunshine, and Frisk becomes the ambassador for the humans. This is perfect happy ending, or at least it would be if Asriel had kept one of the human souls. Fucker!
In a skewed reality, Frisk's ambassadorship does not go well due to political corruption of the surface (Doesn't that sound familiar? Doesn't that sound too close to home?). Frisk is placed back in their orphanage and not allowed to see their new friends again. Frisk is pushed to their breaking point when Papyrus is killed by an angry adult human. Frisk has no choice but to perform a True Reset, much to Sans's disappointment. The True Reset erases everyone's memories including Frisk's and Flowey's, but one person does remember: Chara.
Chara takes full control of Frisk and kills everyone in the Ruins, going so far as to hunt down every last enemy in the area. When Toriel says she wants the human to prove themself, Chara strikes down Toriel in one blow. Toriel finally gets it through his thick freaking skull that the human is now armed and dangerous (not to mention genocidal). Flowey realizes this is indeed Chara's handywork and tells Chara that he is happy to see them return to the Underground and encourages their killing everyone.
The human proceeds to Snowden and meets Sans, who still performs the same trick as before, but since Chara doesn't laugh, he is irked and remarks, "Geez, lady, you sure can pick 'em," referring to the promise he made to Toriel. Chara meets Papyrus without even bothering to hide behind the conveninetly placed lamp. Sans tells Chara that he can tell they're not human, but that for Papryus's sake, it might be best if Chara continues pretending to be. Frisk continues to ignore Papyrus's puzzles or interfere with the skeleton brothers' quarrel about whether crossword puzzles or junior jumbles are harder. Chara goes to the shop and finds that it has been abandoned and steals money from it. The human once again encounters Papyrus east of Snowden town and kills him in one shot after he offers them mercy.
They proceed through Waterfall and again have the displeasure of interacting with Monster Kid. Chara eventually loses their temper and attempts to strike down Monster Kid (who somehow has better stats than Sans), but Undyne stands in their way. She is mortally wounded, and she tells Monster Kid to run far away. Amazingly, she finds the courage to not only keep fighting at this point but achieve a new dangerous form. Undyne the Undying give Chara quite a work out and about five resets before finally giving up upon the depletion of her health.
With the strongest being in the Underground dead, Chara proceeds to Hotlands. Mettaton has apparently been waiting for Chara and has ordered Alphys to evacuate the citizens of Hotlands (though there's still a lot of monsters left to fight for some reason). Mettaton says he has deactivated the traps and will be waiting for Chara in the CORE. Chara visits Burgerpants who is strangely enough, still working at the fast food joint (though Catty and Bratty are gone). It seems that Burgerpants has Stockholm syndrome and doesn't want his sense of false imprisonment to stop.
It's worth noting that Sans hasn't shown up to take the human to dinner at Hotel Mettaton, making this the only route in UnderTale without the theme "It's Raining Somewhere Else."
Mettaton delivers a different speech this time and transforms into Mettaton Neo, an attack-oriented robot with a power level higher than Asgore's. However, Chara attacks first and fatally wounds Mettaton Neo in one shot.
The human continues through the capital, but no one is left alive to tell the human about Asriel. That is, except Asriel himself. Flowey tells Chara that after the two of them originally died, Flowey woke up as a flower. Without his soul, he was unable to care about the well-being of his parents anymore. It didn't hurt him to see his father Asgore in pain. He spetn weeks with Asgore, but couldn't find it in him to feel sympathy. Toriel couldn't help either. Flowey then straight-up committed suicide, but he found the power and desire to reset to a previous save point. Flowey went through thousands of different routes, at first favoring decisions to help people but slowly becoming more and more genocidal due to his psychopathy. Flowey then remarks that he could never predict Chara, which is why Chara is the only one he really cares for as a flower. Flowey, the dumb shit that he is, again encourages Chara to finish the job of genocide, only to realize this includes him. He runs off to parts unknown.
In the final corridor, Sans realizes he must stand in Chara's way. He tells Chara that "do you wanna have a bad time? because if you take another step, you are really not gonna like what happens next." Chara steps forward. Sans remarks, "Sorry, lady, this is why I can't keep my promises." (It's 100% not clear why he didn't draw the line at the "human" killing his brother.)
The battle starts. Sans says, "It's a beautiful day outside. Birds are singing. Flowers are blooming. On days like this, kids like you... Should be burning in Hell." Sans now has a glowing eye flashing blue and yellow. He launches a powerful series of attacks, which ignore invincibility frames (meaning Chara takes damage 30 times per second) that kills Chara. Chara resets and Sans remarks that "That is the face of someone who just died." Sans makes his speech about children dying and going to Hell (which would be weird enough for him to say once, even against a genocidal monstrosity), and kills Chara again. After another resets, Sans says Chara has "the face of someone who just died twice in a row." The process repeats. Sans says Chara has "the face of someone who just died thrice in a row. what's more than thrice. only one way to find out..." Chara dies again. Sans says Chara has "the face of someone who just died quice in a row. Quice?" Another battle ensues. Sans says Chara has "the face of someone who just died five times in a row. That's the number of fingers on one hand." Chara dies for the sixth time. Sans remarks, "That's the face of someone who just died six times in a row. Hmm, that's the number of fingers on a mutant hand..."
Chara finally manages to dodge enough of Sans's attacks to survive the first turn. Chara finally attacks, but in a stunning turn of events, gently steps out of the way of Chara's attack, remarking, "what? were you expecting me to just stand there and take it?" He launches another attack that kills Chara again. Sans continues to comment on Chara's expression after each death, going to far to say, "be careful. You might hit the jackpot." Chara continues to die against Sans's first attack a few more times before Sans eventually loses track of Chara's death count.
After 65 deaths, Sans remarks, "Let's just get straight to the point." The final battle truly begins. As Chara continues dodging, healing themself, and attempting to hit Sans, Sans explains why he's so lazy. Sans was apparently working with someone when they discovered the anamoly in space in time that is the human resetting the world of UnderTale. He soon grew a sense of nihilism, believing any progress he will make will ultimately be undone when Chara resets. "To be blunt," he says, "it makes it hard for me to give it my all." Sans says he can't afford not to care anymore. Sans does offer Chara mercy (though if they gave in, it would result in Sans using an "off-guard" betrayal attack that involves Chara being cut by bones growing from one end of the hallway to the other), but Chara declines by swinging her knife again. Sans continues to use his power of "integrity" determination to throw Chara around the room with gravity, with the lack of invincibility frames still in place. Amazingly enough, Sans also uses Karmic Retribution, a power used by the souls of Justice. It deals extra damage based on how bad a person someone is, draining the player's health one hit point at a time.
Sans starts threatening to use his special attack in a throwback to better memories with Papyrus attacking the human. Sans deals a very long and powerful attack. Several blackouts occur between attacks with Sans throwing everything but the kitchen sink at the human. It ends with a long series of his Gaster Blasters firing one by one, forcing the human to run in a circle carefully, so as not to run into the beams. Sans starts throwing Chara around the room, but cannot seem to finish them off.
Finally, he says he's ready to use his special attack and remarks "here goes nothin'." He does nothing and then explains that he won't let Chara have their next turn because his attack is not going to stop until they give up, "even if it means we [Sans and Chara] must stand here until the end of time." Half and hour passes. Sans becomes sleepy. The lazy bastard actually manages to fall asleep in spite of Chara's reign of terror. Taking advantage of this moment of weakness, Chara attacks Sans one last time. Sans dodges and asks if they honestly expected Sans to fall for this.
Sans was too soon to celebrate.
Chara grabbed her knife she launched into the air after attacking Sans, and she executed the second half of her attack, killing Sans in one hit. Sans says one last thing before he dying, "don't say i didn't warn you. i'm going to grillby's." He walks off screen. "papyrus, you want anything?" he says to the deceased Papryus seconds before he turns to dust.
With the last line of resistance gone, Chara continues to the Throne room. Asgore doesn't recognize that Chara is human due to a side effect of leveling up so much and so quickly. Chara kills Asgore with their knife. Flowey once again surrounds Asgore with bullets and kills him. He makes a huge mistake by destroying his soul, screwing up Chara's plan to escape the Underground. Flowey tries to remind Chara that they are siblings, but is soon mutilated by their attacks.
Chara begins talking to You and commnnts on how much they loved it each time their stats went up. Chara requests You to agree to destroy the timeline, the world of UnderTale completely. Regardless of the answer, Chara does so, taking out the entire universe.
It's possible for the player to sell their soul to Chara in exchange for restoring the world of UnderTale. However, while the true reset erases Flowey's memories, it doesn't erase Chara's, so Frisk remains corrupted, being forced to kill all her friends even after a True Pacifist Run. That's right. You can't even enjoy the True Pacifist ending. The game is hardcore. This is exactly what happens when you commit Genocide.
- Sans and Papyrus were created from the souls of Mario and Luigi respectively.
- Prior to Frisk's arrival in the Underground, Mettaton's programs averaged a viewership of 3,000 monsters, though oftentimes, it would exceed 5,000 and sometimes nearly reach 6,000.
- Top scientists at Wumbo University estimate that God of Hyper Death Asriel's power level is 10,000,000, though a few other different estimates exist. Some say it's as low as 8,000,000 while others say it's as high as 20,000,000.
- By comparison, Photoshop Flowey is said to have a power level of about 150,000. That last human soul would have really made a difference apparently.
- The highest power level with an exact number is Undyne the Undying in the Genocide Route. Her power level is 360. However, under normal circumstances, Undyne has a power level of about 60. King Asgore's power level is 80.
- Mad Dummy's invulnerability to physical attacks and Mettaton's invincibility make them super OP. They have been banned from most Pokémon video game tournaments, some Yu-Gi-Oh! card game tournaments, and all Super Smash Bros. Melee tournaments.
- Prior to the war on monsters, the most human souls absorbed by a monster was 4. However, it's very rare for a monster to ever absorb more than one human soul. There was one instance of a monster absorbing two at a time, and none of a monster absorbing three at a time. Monsters are pretty lame in this regard.
- Although this fact does not include events in the pre-history of this world, it's entirely possible the monsters were only coincidentally correct about the prophecy and that a monster had never absorbed seven human souls before.