Flowey

Howdy!

I'm FLOWEY!
FLOWEY the FLOWER!— Flowey introducing himself.

Flowey () is the first major character that encounters in . Flowey serves as the main antagonist for the majority of the game, specifically the and routes. He provides an introduction to the mechanics of by sharing "friendliness pellets," which are actually harmful bullets, revealing his philosophy of "KILL or BE KILLED."

Contents[]ProfileAppearance

Flowey mimicking the protagonist.

Flowey appears as a sentient who usually grins passively. His structure has a white androecium, six yellow petals, and a light-green stem. Flowey can contort his face to show various expressions and can mimic the faces and voices of other characters. He mimics and in some situations, as well as his at the end of the . He also mimics the protagonist's face before the Neutral Route's final battle.

PersonalityI wonder... What happens when something without a SOUL gains the ?— Entry Number 8, ,

Flowey winks at the protagonist just before sending some "friendliness pellets" their way.

Initially, Flowey operates under a façade of friendliness and politeness. He often greets the protagonist with southern slang, such as "Howdy!", calls himself "your best friend," and, like his father, appends polite words such as "gosh" and "golly" to the ends of his sentences. Whenever he drops this guise of friendliness, he often calls the protagonist an "idiot."

Flowey has a malevolent and cruel disposition, berating the protagonist for not following his "kill or be killed" philosophy. Despite this, he also criticizes the protagonist at the end of the if they killed any monster. He is manipulative, devious, and a cunning planner and subtle if the circumstances require it. He retains his memories between because he was once able to SAVE. He is also shown to be extremely cowardly, as he kills his former father to appease the protagonist in a vain attempt to save his own life in the Genocide Route's conclusion.

Main StoryRuins Start

Flowey showing his true colors before attempting to kill the protagonist.

Flowey introduces the concept of the and calls his bullets "friendliness pellets."

If the protagonist dodges three times, his friendly act slips and he hypocritically snaps at the protagonist for toying with him.The background music lowers by one semitone each time the bullets are dodged, before slowing, lowering pitch, and stopping entirely.Before his third attack, Flowey screams "RUN. INTO. THE. BULLETS!!!" before quickly looking directly at his text and changing the "BULLETS!!!" in the speech bubble to "friendliness pellets."

When the protagonist runs into his bullets, he announces his central philosophy. Regardless of whether the protagonist dodged Flowey's bullets or not, he then attempts to kill the protagonist with an unavoidable ring of bullets, but Toriel intervenes and saves the protagonist.

If the protagonist killed Flowey on a previous Neutral Route, he does not appear. If the protagonist spared him, he reminds the protagonist not to kill anyone. If the protagonist gained no , he reminds them to befriend everyone. After resetting a Neutral Route multiple times and repeating Flowey's initial encounter, he becomes annoyed and questions if "you have anything better to do."

If the protagonist resets a Genocide run before or after killing Sans, Flowey says "Really, <Name>? Well, do what you will. I'll be waiting for you!" before leaving.

Ruins End

At the exit to the Ruins, Flowey judges the protagonist's actions up to that point. Flowey does not appear to judge the protagonist if he was killed in a previous Neutral Route.

[] The following dropdown may contain spoilers.If The Protagonist Spared Toriel(If they have earned EXP)Clever. Verrrryyy clever.You think you're really smart, don't you?So you were able to play by your own rules.You spared the life of a single person.Froggit, Whimsun. Vegetoid, Loox. Migosp, Moldsmal.Think about those names.Do you think any of those monsters have families?Do you think any of them have friends?Each one could have been someone else's Toriel.Selfish brat.Somebody is dead because of you.(If they have not earned EXP)I bet you feel really great.You didn't kill anybody this time.But what will you do if you meet a relentless killer?You'll die and you'll die and you'll die.Until you tire of trying.What will you do then?Will you kill out of frustration?Or will you give up entirely on this world......and let ME inherit the power to control it?I am the prince of this world's future.Don't worry, my little monarch, my plan isn't regicide.This is SO much more interesting.(If the protagonist killed Toriel before)Clever. Verrrryyy clever.You think you're really smart, don't you?So you were able to play by your own rules.You spared the life of a single person.But don't act so cocky.I know what you did.You murdered her.And then you went back, because you regretted it.Ha ha ha ha...You naive idiot.Do you think you are the only one with that power?The power to reshape the world...Purely by your own determination.The ability to play God!The ability to "SAVE."I thought I was the only one with that power. But...I can't SAVE anymore.Apparently YOUR desires for this world override MINE.Well well.Enjoy that power while you can.I'll be watching.If The Protagonist Killed Toriel(First time)I hope you like your choice.After all, it's not as if you can go back and change fate.In this world, it's kill or be killed.That old hag thought she could break the rules.She tried so hard to save you humans.But when it came down to it...Hee hee...SHE COULDN'T EVEN SAVE HERSELF.WHAT AN IDIOT!!(Second time)Ha ha ha ha ha...You disgusting animal.You didn't even TRY to spare her.(Subsequent times)Wow, you really can't get enough.You kind of remind me of myself.(If Toriel was spared before)Wow, you're utterly repulsive.You spared her life...Then you decided that just wasn't interesting enough for you.So you murdered her just to see what would happen.You killed her out of boredom.Truly disgusting...Ha ha ha ha...You naive idiot.Do you think you are the only one with that power?The power to reshape the world...Purely by your own determination.The ability to play God!The ability to "SAVE."I thought I was the only one with that power. But...I can't SAVE anymore.Apparently YOUR desires for this world override MINE.Well well.Enjoy that power while you can.I'll be watching.If Genocide Route Requirements Are MetHahaha...You're not really human, are you?No. You're empty inside. Just like me. In fact...You're <Name>, right?We're still inseperable, after all these years...Listen. I have a plan to become all powerful.Even more powerful than you and your stolen soul.Let's destroy everything in this wretched world.Everyone, everything in these worthless memories...Let's turn 'em all to dust.An audio clip then plays of Flowey exclaiming "That's a wonderful idea!"If Toriel hasn't been metError!Flowey's sound is heard repeatedly and dialog box can't be closed by "Z"Neutral RouteIf you let me live... I'll come back. I'll kill you. I'll kill everyone. I'll kill everyone you love.— Flowey, if spared after his boss battle.

After the Ruins, Flowey will be seemingly absent until the end of Asgore's battle. However, backtracking in some rooms allows the protagonist see Flowey burrowing back into the ground on the edge of the screen.

Flowey's message on an Echo Flower if Toriel was killed.

Flowey also leaves a message on an in the vertical room before the bridge in that changes if the protagonist spared or killed Toriel.

Flowey absorbs the human SOULs.

If the protagonist decides to kill Asgore, Flowey appears, destroys Asgore's SOUL, and absorbs the . If the protagonist spares Asgore, Flowey appears and kills Asgore himself. Then, the game crashes and Flowey's battle begins after opening the game again.

After he is defeated, the protagonist has the chance to spare or kill Flowey. Flowey requires the protagonist to offer him mercy multiple times before he flees, unsure why the protagonist is being nice to him.

If the protagonist loads or finishes another Neutral Route, Flowey does not absorb the SOULs because he knows that they would rebel again. Instead, the protagonist will be able to exit the room and receive Sans's Neutral Route phone call.

Well. You DID do what I told you. I guess it's up to me to get you a REAL happy ending.— Flowey

Flowey's reaction if spared.

If spared after his battle, Flowey advises the protagonist during subsequent Neutral Routes. If the protagonist gained EXP before his battle, he asks the protagonist to prove his philosophy wrong, as he thinks it may be meaningless. Flowey also offers unique dialogue if the protagonist only killed Asgore and tells the protagonist that they wasted everyone's time. If the protagonist earned no EXP, yet they have not met all the requirements for the True Pacifist Route, he mentions that the protagonist should get closer to one of the main characters, depending on who they previously befriended.

The protagonist can then recover their previous SAVE file and follow his advice.

If the protagonist kills Flowey, he recognizes that the protagonist can kill before becoming "just a regular flower."

If he was killed after his battle, Flowey does not leave a message for the protagonist after the credits close, and, after a reset, does not appear until after the resolution of Asgore's battle. Flowey then berates the protagonist for thinking that killing him solved anything. He explains that he was brought back when the protagonist loaded their SAVE file and that they still cannot achieve their happy ending.

If the protagonist nearly completes a Genocide Route but resets after killing , Flowey becomes upset with the protagonist. However, he then proclaims that the protagonist just wanted to see everything in the Underground and will eventually return to their malicious ways.

True Pacifist RouteFor further information, see .Genocide RouteFor further information, see .In BattleAttacksFor an in-battle description, see .

As a flower, Flowey uses only three attacks: a five-bullet spread that slightly hone in on the protagonist's SOUL, a large ring of bullets which surround the SOUL and cannot be dodged and a vertical row of bullets which come from the side of the Bullet Board, from outside it. This attack is only used before his battle as Asriel Dreemurr. He can speed up the spread though the limits of his attacks and speed are unknown. Getting hit by his five-bullet spread in his first encounter deals 19 damage per bullet whereas the unavoidable ring attack heals 19 HP regardless of whether it hits the protagonist. Before his battle as Asriel Dreemurr, the bullets deal 7 damage until 6 HP where it is 5.

Toriel

  I am TORIEL, caretaker of the RUINS.  
— Toriel introducing herself.

Toriel ( TOR-ee-el) is the second major character encounters in . She saves the protagonist from and guides them through the .

Contents[]ProfileAppearance

Toriel with her reading glasses, seen on the title screen if the protagonist spares her.

Toriel is a whose head resembles a white-furred , structured with droopy ears and short horns. She has a pair of visible fangs and long eyelashes, and her irises have a dark red tint. She has an anthropomorphic body, with paws at the end of her limbs. She wears a long purple robe that displays the on her chest. Toriel is seen with her reading glasses, one instance being in when reading a book on snail facts.

Personality

Toriel is a kind monster that acts as a protective mother for the protagonist. She employs tough love on the protagonist as well as . She cares for children and was excited to become a mother.

She enjoys cooking and bakes as well as her favorite, .

Toriel has a playful side and loves puns and bad jokes, and she even keeps a journal of puns.

Toriel is said to be intelligent and dreams of becoming a teacher. She has already prepared a curriculum for the protagonist by the time they reach her home in the Ruins. In the , she stands outside a school and, in the of a , she starts her own.

Main Story

Before the events of Undertale, she was married to King Asgore and had a son, . When fell into the , she adopted them as their child. The deaths of their two children pushed Asgore to declare war on humanity, and as a result, she divorced him, abdicated her throne, and retreated to the Ruins.

Between then and the time the protagonist enters the Underground, she had seen Asgore murder and reap their .

Neutral Route

Toriel guides the protagonist through the Ruins.

At the beginning of the game, Toriel saves the protagonist from Flowey, healing any damage done by the murderous flower. After introducing herself, she guides them through the first few rooms of the Ruins. She encourages the protagonist to deal with monster by talking to them, as opposed to acting violently.

She gives the protagonist a to keep in contact with one another, as she needs to run some errands further into the Ruins. She tells them to stay where they are, only to be disobeyed. She calls the protagonist frequently as the protagonist goes through the Ruins, and is about to call them again when she finds the protagonist at the entrance to her home.

She introduces the protagonist to their room and plans to raise them as her own. After the protagonist asks her about leaving the Ruins, Toriel abruptly leaves; the protagonist follows.

As she goes toward the exit of the Ruins, she explains that she plans to destroy the exit to prevent the protagonist from leaving, as all other humans who left had died.

Toriel hugging the protagonist.

At the end of the Ruins, Toriel tells the protagonist to prove themself strong enough to survive and fights them in a test of strength. She can be killed or spared; if spared, Toriel lets the protagonist go but tells them not to come back.

tells the protagonist during their rendezvous, that he and Toriel have been friends for a while, bonding over their love of jokes and puns. Neither of them knows each other's name or face, as they communicate through the door that blocks off the Ruins.

Sans also says that Toriel asked him to protect any human that left the Ruins. He remarks that if not for that promise, the protagonist would be "dead where [they] stand."

For information on her ending, see .True Pacifist Route

Toriel reappears just as Asgore and the protagonist prepare to fight, interrupting it with her fire magic, much like she does with Flowey at the start of the game. She explains the motive of her arrival was the realization that the protagonist would have to take a life to leave, and that she had been trying to prevent such a thing from the beginning.

As the protagonist's friends come, she introduces herself to them and recognizes Sans's voice immediately. She tells the protagonist that while they may have to stay Underground with all their friends, they will live a happy life regardless.

Flowey then appears. Having absorbed the human SOULs, he binds Toriel and company with vines. When Flowey tries to kill the protagonist, Toriel is the first monster to intervene, using her fire magic to block Flowey's bullets. Her SOUL, along with every other monsters', is eventually absorbed by Flowey, allowing him to become Asriel.

During the protagonist's , Toriel appears as one of the .

Epilogue

After the fight against Asriel concludes, she learns the protagonist's name, "Frisk." She tells them that they are free to go through the Underground to talk to more of their friends. Meanwhile, Alphys upgrades Toriel's , allowing her to send text messages.

Toriel standing outside the school.

Frisk leaves the Underground with Toriel and their other friends. As the others leave Frisk to begin their lives on the , Toriel asks Frisk what they will do now.

If Frisk decides to stay with Toriel, she says that none of this would have happened and that it was for the best that they decided to leave the Ruins. She then promises to take care of Frisk for as long as they need. Like in the Ruins, Toriel takes Frisk's hand as they walk offscreen together. After the credits, Toriel brings a slice of pie to Frisk's room.If Frisk says that they "have places to go," Toriel says that she will see them later. After the credits, Frisk and their monster friends are shown together in a sepia photograph.

In the credits sequence, Toriel welcomes to a school that she opened and teaches at. The school door is adorned with the Delta Rune without the triangles that represented the monsters trapped Underground.

In BattleFor an in-battle description, see .RelationshipsThe Protagonist

Toriel cares for who fall into the Ruins, and the protagonist is no exception. She tries to keep the protagonist in the Ruins, as Asgore killed the other humans who left her care. If the protagonist spares her, she lets them leave the Ruins, but not before giving them a parting hug.

Toriel's reaction if the protagonist kills her after she is spared thirteen times.

If the protagonist kills her during a Neutral Route, she uses the last of her strength to give them a warning about what lies ahead and calls the protagonist "my child" before she turns to dust. If the protagonist kills her when she offers mercy, she says that the protagonist is like the monsters outside the Ruins. In the Genocide Route, she realizes that the protagonist is dangerous and laughs hysterically before she dies. The death sprite for Toriel is the same in a Genocide Route and on a Neutral Route if the protagonist kills her after she is spared thirteen times.

If the protagonist calls Toriel "mom," it surprises her, and she states that if it makes them happy, then she heartily approves of it.

Calling Toriel on her phone in the Ruins and flirting with her makes her assume the protagonist is joking, if they do it again she is unsure what to make of it. If they flirt with her after calling her "mother," she becomes uncomfortable and calls the protagonist an "interesting" child. She also mentions this in the epilogue.

If the game is reset, Toriel says that talking to the protagonist is like "meeting an old friend for the first time" and also says that she feels this way about most fallen humans.

Asgore

Asgore is Toriel's ex-husband. They were once extremely close, winning first place in the '98 Nose Nuzzle competition and were open about their affection for one another. During their marriage, Toriel's nicknames for Asgore included "Fluffybuns" and "Gorey."

Toriel left Asgore and after he declared war on humanity. After they are reunited on a True Pacifist Route, Toriel criticizes his plan for freeing monsters but still believes that he deserves mercy, even though he is "terrible." When Asgore asks if they can be reconciled or at least be friends, Toriel declines. While she appears to be civil with Asgore when she speaks to him about the future of the Underground in the aftermath of the fight against Asriel, once they are on the surface and everyone else has left, Asgore wonders whether he should leave too, and Toriel glares at him, prompting him to leave her and Frisk alone. However, in the ending credits, she allows him to trim the hedges outside of her school, showing that she's starting to forgive what Asgore has done and may begin to make amends with him.

Flowey

Toriel calls Flowey a "miserable creature" as she fireballs him to protect the protagonist. She is unaware that Flowey is Asriel.

Sans

Sans and Toriel do not meet in person until the end of a True Pacifist Route and the and endings, where they both have become good friends. They started their friendship by telling jokes to each other through the door leading to the Ruins. One day, Toriel entrusted Sans with protecting any human that left the Ruins.

They continue to bond in the epilogue and text each other as Frisk backtracks through the Underground.

TriviaToriel's name is a play on the word "tu-torial," as she teaches the protagonist about how the game works.Despite Toriel's motherly nature, she is not above swearing: stated in a deleted tweet that it is possible for Toriel to have said the "F-word." But later, he also mentioned that his tweets etc. are not canon.According to Sans, at some point after the events of the game, Toriel drank three glasses of wine and threw pizza at him like frisbees.Toriel has a sock drawer despite never wearing socks in-game.The narrator's reaction to Toriel's sock drawer and Sans's sock pile is similar.Toriel once wore a flower-patterned muu-muu; other monsters complimented her by saying "nice muu-muu," but she assumed everyone was calling her a cow and never wore it again.

Toriel's initial reaction to the protagonist boring the Dummy.

If the protagonist bores the during their encounter, Toriel stares in disbelief and confusion and starts thinking in a confused manner before moving to the next room without comment.When attempting to the fallen human "Toriel," the response is: "I think you should think of your own name, my child," and prevents the name from being used.If Toriel was killed and the protagonist resets to the point before her battle, Toriel remarks that the protagonist looks like "they have seen a ghost."Toriel and are the only bosses that the protagonist can flee from in battle.If the protagonist spares Toriel, she can be found by the flowerbed where the protagonist initially awoke. If the protagonist backtracks to talk to her, she tells them "Do not worry about me. Someone has to take care of these flowers."Asriel also says this if you backtrack to the same location after completing a .The player cannot call Toriel once they exit the ruins even if she was spared. While most players may assume that Toriel intentionally refuses to answer the protagonist's calls outside of the Ruins, she is actually unable to answer due to the having stolen her phone.Calling her with the Annoying Dog in the inventory causes ringing in the protagonist's inventory, implying that it stole and ate her phone.Attempting to open the menu by pressing C after fleeing her battle will have the menu disappear instantly, leaving the room will not reproduce the error.

Sans

i'm sans.
sans the skeleton.— Sans introducing himself.

Sans ( SANZ) is the brother of and a major character in . He first appears in after exits the . He serves as a supporting character in a and and as the final boss and heroic antagonist in a .

[]ProfileAppearance

Sans is a short skeleton with a dimpled smile and large orbits. He wears an unzipped blue hoodie, a white t-shirt/sweater, black shorts with white stripes, and a pair of sneakers/slippers. He has white pupils that disappear when he is serious or angry. When Sans uses magical psychokinesis, his left eye flashes light blue and yellow, the colors for and , and his right pupil disappears.

Personality

Sans is laid back, often sleeping on the job and taking breaks. His laziness is a combination of fatalism and apathy. He wonders if his indolence stems from his knowledge that any progress he makes will be erased when the timeline resets. Conversely, he suggests that this knowledge could be "a poor excuse for being lazy."

Though Sans is usually agreeable, he becomes eerily serious at particular moments. He is also observant; Sans reads the protagonist's expressions and can often tell when they have already done certain tasks. He enjoys making bad, skeleton-related puns, although the fact that he performs at hints that he may be a talented comedian. He enjoys science fiction and loves to drink ketchup. He also hates making promises.

Sans may have a scientific background. Evidence includes the quantum physics book, , his relationship to , affinity for science, and his timeline research.

Abilities

Sans can quickly travel or teleport using what he calls "shortcuts."

A "Gaster Blaster" that Sans uses in battle.

In combat, he uses " Blasters," devices that resemble a skull, to shoot a kind of laser beam. Sans excels in combat and fights with unique abilities that include: , changing the effect of gravity on the , and attacking the protagonist in the selection menus. His magic reacts to ; Karmic Retribution would presumably be weaker if the protagonist had little EXP.

Because of his "research," he has knowledge of timelines and the function. However, he does not retain his memories when the protagonist loads a SAVE, and he cannot use the SAVE function. His awareness of time travel makes him scrupulous, and he recognizes when the protagonist is behaving unusually. Sans reads the protagonist's expression and determines if they have experienced events before and are repeating them. He also knows how much EXP the protagonist has and comments on it when judging them.

Sans also plays the trombone, though he is only seen playing it once. Papyrus finds his "incidental music" annoying, implying that he has played many times before.

Like other characters, Sans is aware of when the game's code suffers bugs and calls the protagonist a "dirty hacker" if they achieve an impossible ending of a Neutral Route.

Main StoryNeutral Route

Sans's first appearance in Snowdin Forest.

Sans introduces himself to the protagonist in Snowdin Forest after he initially appears as a silhouette. He explains that he has no interest in capturing , but that his brother, Papyrus, does. Then, Sans hides the protagonist behind a lamp whose shape is identical to the protagonist's. Papyrus rushes onscreen, and the brothers discuss Sans's laziness and the importance of puzzle upkeep. Sans appears multiple times throughout Snowdin Forest, observing and commentating on the puzzles but not engaging in any japery, except for the .

Before Papyrus's battle, Sans is absent in . He appears briefly to play trombone during the date/hangout with Papyrus but does not appear again until the if the protagonist kills Papyrus.

A spotlight falls on the protagonist and Sans as "" plays.

After entering , Sans is found manning a sentry station and asks the protagonist if they want to take a break with him. If the protagonist agrees, he takes them to via "shortcut." The patrons warmly greet Sans, and he proceeds to treat the protagonist to a burger or fries. After some dialogue, a spotlight falls on him and the protagonist; time appears to stop as Sans tells the protagonist that a flower has been talking to Papyrus. Sans believes that someone is tricking Papyrus with an when the flower in question is . Sans can be seen again in Waterfall and pranks the protagonist with a red-eye telescope.

The protagonist passes him sleeping at a sentry post in when fleeing from . Undyne notices him sleeping and berates him mid-chase.

Later, Sans sells in Hotland for 30. If the protagonist attempts to buy a hot dog when their inventory is full, he stacks a maximum of 30 hot dogs on their head for free. These "head dogs" vanish when the protagonist enters the next room.

Sans and the protagonist at MTT Hotel's restaurant as "" plays.

Further on, Sans waits outside of MTT Resort and asks the protagonist if they want to grab a bite to eat. He escorts the protagonist inside via "shortcut" and talks about he has befriended that shares his affinity for puns. He tells the protagonist that this woman made him promise to protect any human that left the Ruins and that, if she had not said anything, the protagonist would be "dead where [they] stand." He dismisses this as a joke immediately and says that he has done a great job protecting the protagonist. If the protagonist has not died before, Sans takes credit for their success. If the protagonist has died, Sans questions the validity of his statement. Before leaving, he tells the protagonist to take care of themself because someone really cares about them.

JudgmentThe end of your journey is at hand.
In a few moments, you'll meet the king.
Together...
You will determine the future of this world.— Sans's introduction in the Last Corridor.

The protagonist encounters Sans for the last time in the Last Corridor. He explains that EXP and LOVE are acronyms - "EXecution Points" and "Level Of ViolencE" and judges the protagonist for their current EXP.

If the protagonist gained no EXP, Sans skips his judgment, instead praising the protagonist for embracing compassion and actively choosing to be merciful to the monsters throughout their journey. He reinforces the idea that the protagonist's actions shall decide the fate of the world in one of two ways: the protagonist lets take their SOUL and allow the monsters to break the Barrier or they take Asgore's SOUL to escape the Barrier themselves. Sans concludes that the protagonist now has enough and believes that they can do the right thing before leaving.

Sans's workshop entrance is located behind his house.

If the protagonist has heard his speech before, Sans notices their bored expression and offers a secret codeword that he uses to prove that they are a time traveler. After the protagonist loads their a few times, Sans's suspicions are affirmed and he gives them a key to .Inside Sans's room is a key to his workshop.

If the protagonist gained EXP, Sans allows them a moment to think about their actions. He then emphasizes the importance of integrity and, if Papyrus is alive, concludes that whatever happens next is up to the protagonist. If the protagonist killed Papyrus, Sans expresses his suspicion that they have some special power. He then asks if the protagonist thinks it is their responsibility to do the right thing. Regardless of their answer, Sans reminds the protagonist of his late brother and leaves.

If the protagonist returns to the Last Corridor after loading a SAVE, Sans judges the protagonist on their earned LV. Subsequent attempts to talk to Sans after judgment prompts him to tell the protagonist to "consider our session over."

[] Sans's LV JudgmentsSans's judgment occurs after he re-explains LOVE and EXP, and after he tells the protagonist to look inside themselves.(Before Judgment)huh?you look bored.i get the feeling you aren't gonna learn anything from this.well, guess i gotta judge you then.(LV 1, but more than 0 EXP)... huh?what's with that look in your eye?did you go through and kill someone...just to see what i'd say about it?wow.you're a pretty gross person, huh?(LV 2)lv2...seems like you messed up the slightest amount.welp.that's pretty sad.you probably weren't even aware of what you were doing...and when you learned, it was too late.nah, just kidding.who gets to lv2 on accident?get outta here.(LV 3)lv3...3's just an ok number, i guess.i'll give you a C+.you can do better, right?(LV 4 – LV 9)hmmm...over lv3, huh.you killed some people on purpose, didn't you?that's probably bad.though, maybe some of it was in self-defense...i don't know.help me out here.i wasn't watching.anyways, don't do that.(LV 10 – LV 14)hmmm...over lv9, huh.that's over halfway to lv20, the maximum.but don't think that means you're still 50-percent good.50-percent, 20-percent.those are both still failing grades.besides.chances are...i've already tried to steer you in the right direction.so what can i say?what can i say that will change the mind of a being like you?(LV 15 and Above)hmmm...over lv14, huh.well, hmmm...judgment-wise...you're a pretty bad person.you wander around, looking for people...killing them to take their money.that's just plain messed up.and what's worse, is that as bad as you are...you aren't anywhere near as bad as you could be.you pretty much suck at being evil.honestly, it's super embarrassing.but maybe you'd be better...at not killing anyone?crazy idea, huh?let me know how that one goes.Endings

After the protagonist defeats , Sans calls and informs them of the events that transpired after their departure. The content of this phone call varies depending on the protagonist's actions; a list of the endings that Sans describes is on the page.

True Pacifist Route

Sans is absent from the Last Corridor in a True Pacifist Route. There is also no SAVE point upon entering the corridor. He appears during the pre- cutscene and meets Toriel face-to-face for the first time. Flowey binds Sans and the protagonist's other friends. However, the protagonist's friends protect them from Flowey's attacks before Flowey absorbs their SOULs.

During the battle against Asriel, Sans appears as one of the .

Epilogue

After defeating Asriel, Sans stands alongside the other main characters. If the protagonist talks to him, he says a certain remark depending on what, if anything, the protagonist said to Toriel in calls at the beginning of the game.Sans also to text for her a few times because Toriel's thumbs are too big for the phone buttons. When the protagonist is ready to leave, Sans exits the and heads to the along with the other monsters.

Papyrus runs off to introduce himself to the humans and Sans says someone has got to keep him away from trouble and runs off in the opposite direction, presumably to use a "shortcut."

In the , Sans rides a tricycle on a highway, while his brother races alongside him in a car. Papyrus seems irritated when his brother overtakes him.

Genocide Routeif you keep going the way you are now...
you're gonna have a bad time.— Sans's warning to the protagonist in a Genocide Route

Sans disappears in front of the protagonist.

Sans stalks and introduces himself to the protagonist as usual but requests that they continue pretending to be a human. He does not comment on the protagonist turning around before he asks them to. Sans goes along with Papyrus's japery and does not appear as an NPC as he does on other routes. After the protagonist crosses the bridge before Snowdin Town, Sans warns them not to fight his brother or else they will "have a bad time." He then disappears and is absent until the Last Corridor.

If the protagonist aborts a Genocide Route by sparing Papyrus, Sans reappears at the Waterfall sentry station and tells the protagonist he respects them for doing that. He continues to appear as if on a Neutral Route but does not take the protagonist to Grillby's since there is no one left in Snowdin. Alternatively, Sans follows the protagonist if they kill Papyrus.

Sans's Final Corridor speech in the Genocide Route.

The protagonist encounters Sans in the Last Corridor for his battle.

For further information, see .

After defeating Sans, the protagonist's EXP is set to 99999, granting them LV 20. Sans notices if the protagonist has killed him before and is re-fighting him.

Sans does not count as a kill in the menu, and the game does not record whether or not he is killed.

In BattleFor an in-battle description, see .RelationshipsThe Protagonisttake care of yourself, kid. 'cause someone really cares about you.— Sans after his rendezvous at MTT Resort

Sans's attitude towards the protagonist depends on their actions, though he usually enjoys pranking them and occasionally hanging out with them unless they kill Papyrus. Near the end of a Neutral Route, he judges them on their EXP. At the end of the True Pacifist Route, Sans considers them a good friend.

Sans initially considers the protagonist to be an "anomaly"; his intentions of befriending them were in hopes that they would stop resetting the timeline. However, he also says that the protagonist did not die after their initial encounter because of his promise to Toriel. This may imply he would have killed the protagonist or that he protected them from life-threatening harm after their first encounter.

PapyrusYou dirty brother killer.— Sans during his judgment in one of the Neutral Routes

Sans cares for and admires his brother. He reads him bedtime stories and gives him presents under the identity of Santa. Nonetheless, Sans likes to mess with Papyrus, sending him bad puns on the . He also leaves a dirty sock in their living room for Papyrus to fuss over.

Sans worries about others hurting Papyrus or taking advantage of him. In some Neutral Endings, Sans is afraid to tell Papyrus about other characters' deaths, so he lies about them going on a vacation.

Toriel

Toriel and Sans share a love of bad jokes and are friends even though they never see each other face-to-face until the epilogue, the , or the . Before the protagonist's arrival, Sans and Toriel shared jokes through the door to the Ruins.

In the Exiled Queen Ending, Sans becomes Toriel's roommate if Papyrus has been killed. In this route, Sans also states that he "can't bear to tell her what [the protagonist] did." If Papyrus is alive, the brothers visit Toriel often, play board games together, and sometimes convince Toriel to leave the Ruins.

While not being one to make promises, Sans complies with Toriel's request to watch over and protect any human that exits the Ruins. At the end of a Genocide Route, he indirectly apologizes to her, as he is forced to break his promise to stop the protagonist.

Alphys

Though there is evidence that Sans and Alphys have a relationship, Sans only alludes to this in the epilogue.

It is also noteworthy that if Papyrus and Undyne are called just before entering the , Sans appears in the call and state that there may be dogs inside the lab. This hints that he knows about the true lab since , an amalgamate containing several dogs can be found there.

W. D. Gaster

A few things hint at a connection between Sans and W. D. Gaster. Evidence includes the blueprints and veiled machine found in his workshop, the sprites used for his skull-like laser guns (labeled gasterblaster in the game files), and his unexplained scientific research on the "anomaly" and timelines. Sans and Papyrus are named after a font, as well as W.D Gaster, so it is believed they are related.

Papyrus

I WILL BE THE ONE!
I MUST BE THE ONE!
I WILL CAPTURE A HUMAN!
THEN I, THE GREAT PAPYRUS...
WILL GET ALL THE THINGS I UTTERLY DESERVE!— Papyrus discussing his plans with Sans

Papyrus ( pa-PIE-rus) is the brother of and a major character in . His main motive is to capture a so he can become a member of the .

Contents[]ProfileAppearanceNormal ("Battle Body")

Papyrus is a tall, perhaps anatomically inaccurate skeleton with a skull more vertical and geometric than his brother. Being skeletal, many of his expressions incorporate a toothy grin. His eyes resemble vertical slits; his skeletal pseudo-brows form most of his expressions. He has eyeballs which show at times when he is experiencing strong emotions.

He wears his "battle body," an outfit that he created for a costume party. It includes a white chest plate with gold trim, orange-red gloves with gold trim, blue briefs with a golden belt, and knee-high, orange-red boots. A symbol that resembles that of from the MOTHER series adorns the chest plate.

Befriending (Cool Dude)

Halfway through the date/hangout with Papyrus, he changes into his "secret style": a backward baseball cap, a t-shirt that reads "Cool Dude," small shorts with buttons, gloves with striped trim, knee-high socks, and sneakers. He also wears basketballs on his shoulders, likely 's MTT-Brand FashionBall.

Alphys Date (Jogboy)

The first and only appearance of Papyrus's "JOGBOY" outfit.

During the "date" with , Papyrus arrives wearing a sweatband, shorts, and a t-shirt that reads "JOGBOY," with hearts on the pauldrons. He still wears his boots, gloves, and cape.

Personality

Papyrus is a flamboyant skeleton who presents a confident, charismatic image of himself. He works hard and, despite his brash personality, is kind at heart. He is optimistic and innocent even when the protagonist beheads him in a . He is also occasionally oblivious and nonobservant, but can be cunning at times, as seen when he uses reverse psychology to trick into befriending .

Papyrus believes in others just as much as he believes in himself. He has so much faith in his abilities that he waited outside of Undyne's house all night and begged her to accept him into the Royal Guard. Seeing his persistence, Undyne offered to train him but instead gave him cooking lessons.

Papyrus's Room.

He cooks spaghetti in his spare time, though many characters seem to think that he is not very good at it. One of the reasons for this is because Papyrus never ate spaghetti himself to complete the chef's guidebook to cooking by tasting their creation before serving. He, therefore, cooks spaghetti only because everyone else loves to eat it, indicating he does not play favorites. He loves puzzles and japes, as shown in the numerous puzzles he prepares for the protagonist as well as his collection of "complex tomes about puzzle creation." Though advanced puzzles may seem cerebral, Papyrus also enjoys children's books and is somewhat childish in his room decor. He also collects action figures.

Papyrus also watches Mettaton's TV shows, and idolizes Mettaton so much that he would move to , a region that he dislikes.

Main Story

Sometime before the events of Undertale, Papyrus and his brother showed up one day in Snowdin and asserted themselves. Sometime after that, Papyrus became friends with Undyne and began training with her.

Neutral RouteWHAT ARE YOU LOOKING AT!?
THIS WAS ANOTHER DECISIVE VICTORY FOR PAPYRUS!!— Papyrus after

Papyrus's first appearance in Snowdin Forest while "" plays.

Papyrus first appears in , where he proclaims to Sans that he will capture a human and become popular. Papyrus, ignorant of the human hiding nearby, berates Sans for not recalibrating his puzzles. Further in the forest, Papyrus meets the protagonist for the first time, though he initially confuses them for a rock.

Papyrus attempts to antagonize the protagonist with puzzles and japes, but he eventually warms up to them. He almost refuses to fight the protagonist out of pity. Though Papyrus initiates an , he never kills the protagonist and instead places them in if their reduces to one. The protagonist can easily escape his shed.

Ultimately deciding that the protagonist is friendly, Papyrus lets them continue into , advises them on how to exit the Underground, and offers either a hangout or a date back at his house.

Hanging out with Papyrus.

Returning to Papyrus's home after Papyrus's fight initiates the hangout or date. Papyrus dresses in his "secret style" and hides a special gift under his hat for the protagonist. Ultimately, Papyrus decides that the protagonist cares too much about him for their own good, and sends them back on their way with his phone number, which the protagonist can call at any time to hear his opinions about the room that they are in.

When the protagonist makes their way into Waterfall, Papyrus attempts to sway Undyne from killing them; Undyne refuses to yield, however, and Papyrus finds himself obligated to help her. He calls the protagonist and asks them to confirm what they are currently wearing. Papyrus is loyal to both Undyne and the protagonist by employing a ruse that backfires regardless of what the protagonist does.

Papyrus escapes the protagonist's date with Undyne.

If befriended, Papyrus calls the protagonist while Undyne is chasing them and say that they should all hang out. Backtracking to during the chase leads to the protagonist discovering Papyrus already waiting outside her house. After the protagonist chooses whether or not to give Undyne water in , they can go to Undyne's house, and Papyrus offers dialogue based on the protagonist's actions after his call.

He flees from the date early on, after using reverse psychology to get Undyne to befriend the protagonist.

True Pacifist RouteTHAT'S RIGHT, HUMAN! YOU CAN WIN!!
JUST DO WHAT I, WOULD DO...
BELIEVE IN YOU!!!— Papyrus

Befriending Papyrus is necessary to finish a . guides him to call all the protagonist's friends to .

Before 's boss battle, Papyrus rushes to intervene with the battle between and the protagonist.He then meets for the first time and becomes annoyed once she tells him a pun.

Flowey then restrains Papyrus and the rest of the monsters present with vines. Papyrus defends the protagonist from Flowey's bullets and states his faith in the protagonist.

Epilogue

In the credits, Papyrus is overtaken by Sans, who is riding a tricycle.

Papyrus discovers that there is no need for the Royal Guard anymore and proclaims that this is "THE WORST POSSIBLE ENDING." He also comments that Toriel is a "HUGE DORK."

In the , it seems many of Papyrus's dreams have come true: he drives a red car along a highway, something he has always wanted to do. Later on, Asgore is shown trimming a hedge in the shape of Papyrus's face, something that Papyrus wished would happen once he became a famous royal guardsman.

Genocide Route

The protagonist approaches Papyrus.

In a , Papyrus pulls much of the same antics that he does in a Neutral/Pacifist route, except often cites the protagonist's unwillingness to complete his puzzles. He remains oblivious to the protagonist's motives until their battle, where he instantly spares them, wishing to guide the protagonist on a better path and be friends. The protagonist can then spare or kill Papyrus.

If the protagonist kills him, he states he still believes in the protagonist and thinks that they can become a better person. If they decide to spare him, Papyrus proclaims that they "DIDN'T DO A VIOLENCE," and says that he was secretly terrified of the protagonist. From that point on, the protagonist may choose to "hang out" with Papyrus, and the protagonist aborts the Genocide Route and move to a Neutral Route.

In BattleFor an in-battle description, see .RelationshipsThe Protagonist

Despite wanting to capture the protagonist, Papyrus still cares about them and eventually ends up dating/hanging out with them if the protagonist does not kill him. He turns the protagonist down if they choose to date, as he realizes he does not feel the same way about them. Notably, Papyrus hangs out with the protagonist even if they had been on a Genocide Route up until sparing him.

The protagonist remains friends with him throughout the game and gains the ability to call him on the almost anywhere.

Sans

Sans and Papyrus often appear together when presenting puzzles to the protagonist.

Sans is Papyrus's brother, and though Papyrus often chastises him for being lazy and detests his many skeleton puns dropped throughout the game, the two of them care about each other a lot. Papyrus often cleans up after Sans and prompted him to get a job as a sentry.

Papyrus is upset that Sans naps so much and mentions that it's impressive how much slacking off his brother can do. Even though Sans reads Papyrus bedtime stories and is the sole provider in the skeleton household, Papyrus takes care of his brother and wonders what Sans would do without such a "cool guy" watching over him. Together, they made Papyrus's battle body as well as his cardboard sentry station in Snowdin Forest.

Papyrus also recognizes that Sans is secretive and kind of weird.

Undyne

Papyrus and Undyne are good friends. After Papyrus asked to join the Royal Guard, Undyne gave him cooking lessons, and they bonded. Because Undyne does not have the heart to tell Papyrus that she will never let him join the Royal Guard, Papyrus continues trying to impress her by capturing a human. Sometimes Undyne grosses Papyrus out, but Papyrus looks up to her as a role model. Papyrus is also oblivious of when Undyne is angry at him, though he is keen enough to know to present befriending the protagonist as a challenge to her.

Flowey

Papyrus sees Flowey as a good friend because Flowey offers him predictions, flattery, advice, and encouragement. Papyrus also borrows some of Flowey's dialogue characteristics, and Flowey guides Papyrus to call the protagonist's friends to interrupt 's battle with the protagonist.

Undyne

SCREW IT!
WHY SHOULD I TELL THAT STORY...
WHEN YOU'RE ABOUT TO DIE!?!
NGAAAAAHHHHHHHHHHHHHHHHH!— Undyne before her battle

Undyne ( UN-dyne), known as StrongFish91 on the , is a fish-like that leads the . Clad in her full suit of armor, she pursues through the entirety of and is frequently evaded or inadvertently thwarted by the .

Contents[]ProfileAppearanceNormal

Undyne prepares to throw her spear at the protagonist.

Undyne debuts in armor varying in light and dark shades of gray, but without armor, is a piscine, anthropomorphic monster. She has blue scales and a long red ponytail. She has red and blue fins on the sides of her head, and a pair of sharp, yellow, protruding teeth. She wears red eye shadow and has an eyepatch on her left eye. She also wears a black tanktop and jeans. Her eyes have black vertical pupils and a yellow sclera. Undyne has no nose.

Alphys Date

During the date with Alphys, Undyne wears a white turtleneck under a black leather jacket, pants, lipstick, a light-colored eye patch, and lets some of her hair down.

Undying

Whenever she persists through after her reduces to zero, her pupils turn white, and her sclera turns black. She no longer has an eyepatch, and her newly revealed empty eye socket emits a flashing light in the shape of a spear. Her hair spikes at the ends and her fins become more rigid and pointy. She also appears to have donned a new set of darker colored armour with souls/hearts on her chestplate and on her new white gloves, accompanied by boots with pointed toes.

Personality

Undyne is passionate about everything that she does. She acts quickly on her ideas and is steadfast in her beliefs. Though she wants to defeat the protagonist, she also tries to be fair and offers an explanation of how works. taught her the value of pacifism, which is why Undyne sees the protagonist as "a wimpy loser with a big heart." When the protagonist first encounters her, she fights to further Asgore's plan of collecting seven human SOULs but, if the protagonist shows mercy, Undyne just as quickly defends them from Asgore.

She loves to help others and mentors and in various skills. Undyne dislikes puzzles, loves japes, and enjoys anime, an affinity she shares with her romantic interest, . Since Alphys told Undyne that anime is actually human history, Undyne regards human history as exciting and cool.

Out of all encountered monsters, Undyne possesses the most Determination. She melts before her death, implying that her body cannot handle the amount of Determination she has.

Main StoryNeutral Route

The lighting radically changes when Undyne is near.

The protagonist initially encounters Undyne after entering Waterfall, where Undyne stands on top of a ledge. If alive, Papyrus approaches her and attempts to convince her not to harm the human. As the protagonist continues, the grass rustling alerts Undyne to their presence, and she scopes out the grass for a moment before retreating.

Undyne follows the protagonist throughout Waterfall and repeatedly attacks them, but the protagonist always evades capture by either dodging her attacks or due to Monster Kid's interference. Later on, Undyne approaches the protagonist as Monster Kid hangs on to the side of a bridge. If the protagonist saves the Monster Kid, they will protect the protagonist from Undyne. If the protagonist does not help the Monster Kid, Undyne will save them instead.

BUT NOW??? I DON'T CARE! I'M NOT YOUR FREAKING KINDERGARTEN TEACHER!— Undyne when enraged

After this, Undyne confronts the protagonist and stands atop a crag while giving a monologue that she has practiced many times before. However, she cuts the monologue short because she forgot the rest of it and launches head-on into battle.

After Undyne chases the protagonist into , she collapses because her armor heats up. The protagonist can offer Undyne a glass of water, spill all the water in front of her, or continue into Hotland. If she receives water, Undyne stands up, looks around, and slowly returns to Waterfall.

True Pacifist RouteI'll make you like me so much... Your WHOLE LIFE will revolve around me!! FUHUHUHUHU!!!— Undyne on her date with the protagonist.

If the protagonist befriended Papyrus, he calls them during Undyne's chase and suggests that they and Undyne should hang out at her house. If the protagonist gives Undyne water, Undyne will befriend the protagonist if they have no . After Undyne's battle, the protagonist can backtrack to her house and begin their hangout with her.

Undyne is initially hostile to the protagonist but changes her attitude when Papyrus presents befriending the human as a challenge. She realizes that becoming "besties" with the protagonist would be "the perfect revenge," and says that the protagonist will feel "enamored" with Undyne by the end of their date. Undyne discusses her training with Asgore over tea and suddenly realizes that Papyrus's cooking lesson usually occurs at this time. She insists that her and the protagonist bond over cooking, which ends in Undyne's house catching on fire. Humiliated and feeling that she failed at befriending the protagonist, Undyne battles the protagonist and offers them the first hit. No matter the choice, however, the protagonist will only deal one hitpoint of damage. Undyne won't die and realizes neither of them wants to harm one another.

Because her house is engulfed in flames, Undyne moves into .

After the protagonist completes a Neutral Route, they can backtrack from the into , and Undyne will call them to ask for a favor. In , Undyne gives them that she asks them to take to Alphys in Hotland. The protagonist gives Alphys the letter, but she mistakes it as being a love letter from the protagonist because it has no signature. Alphys reluctantly goes on a date to the with the protagonist. After Alphys hides, Undyne sees the protagonist at the dump and asks for her letter back; she wants to give it to Alphys herself. After Undyne walks away, Alphys expresses regret about her lying to Undyne, and the protagonist suggests a roleplay to help Alphys express her feelings. Undyne interrupts the roleplay, and Alphys tells her about her romantic interest. Undyne reciprocates these feelings and tosses Alphys into the trashcan.

Undyne says that Alphys needs to work on her self-image, and Papyrus leaves with Alphys to help with her emotional transformation. After the two leave, Undyne asks the protagonist if anime is real or not and thanks them for helping with Alphys.

Later on, Undyne interrupts Asgore's encounter with the protagonist and demands that they befriend one another. Alphys and Undyne almost kiss before 's ambush, but Toriel chastises them for kissing in front of a child. Flowey ensnares the protagonist's friends with a vine, and Undyne protects them from incoming attacks from Flowey. He then absorbs the six human and most of the SOULs of the monsters in the Underground.

Epilogue

When the protagonist talks to Undyne in the epilogue, Undyne states that she is glad that she lost to the protagonist and then resolves to watch anime with Alphys. The Royal Guard is disbanded. Toriel also texts the protagonist that Undyne was able to lift Asgore, Sans, Papyrus, Alphys, and Toriel herself at once, but was uncertain as to how to put them down.

On the surface, Undyne pursues Papyrus after he runs off to meet more humans. In the , Undyne kisses Alphys on her left cheek and laughs when she faints in embarrassment. She then punches the sidewalk beside her while laughing, causing it to crack.

Genocide RouteYou're gonna have to try a little harder than THAT.— Undyne the Undying

After the protagonist attacks the Monster Kid, Undyne protects them and takes the blow instead. Even though her HP reduces to zero, Undyne holds on through Determination and reforms into Undyne the Undying. If the protagonist defeats her, she tells them that Alphys was watching their battle and has evacuated the rest of the monsters to safety. Undyne begins melting due to her Determination and then turns to dust.

In BattleFor an in-battle description, see .RelationshipsAlphys

Alphys and Undyne have crushes on one another. Undyne first met Alphys in the Garbage Dump, listening for hours about where she thought the abyss there led. The two became close friends soon after, with Alphys introducing her to anime at some point. They hang out often, and Alphys uses the seagrass throughout Waterfall to make a special frosty treat for Undyne. Alphys and Undyne also worked together to create some of the puzzles in Waterfall.

They nearly kiss in the , but Toriel interrupts them and tells them not to kiss in front of the protagonist.

Papyrus

Undyne thinks of Papyrus as a close friend. She is impressed by his persistence and trains him in cooking, but is concerned about his well-being and secretly does not want him to join the Royal Guard because she believes that he is too nice to fight. She teaches him how to cook in hopes that he changes his mind about joining the Royal Guard. Undyne sometimes enjoys messing with Papyrus, but she often forgets that he usually takes things literally. She is heartbroken and infuriated if the protagonist kills Papyrus during a Neutral/Genocide Route.

The Protagonist

Undyne initially despises the protagonist and believes that they would be more useful dead than alive. If the protagonist spares her and offers her water in Hotland, she begrudgingly befriends them if they have earned no EXP. Though Papyrus tricks Undyne into befriending the protagonist, she genuinely cares about them at the end of their date.

If the protagonist earned no EXP and befriended Undyne in a previous route, she remembers them as a friend but brushes off the feeling before her battle.

Asgore

Even though Asgore is her boss, Undyne sees him as a friend and knows his favorite type of tea. When she was younger, Undyne challenged Asgore to a fight but could not land a single blow on him. She was humiliated because he did not fight back and only dodged her attacks. Asgore then offered to train Undyne and eventually promoted her to head of the Royal Guard.

After Toriel fireballs Asgore in the True Pacifist Route, Undyne consoles him because he is crying.

Napstablook

They live in the same neighborhood. They are intimidated by her, but she tries to be a good neighbor to them. She seems concerned about them being alone after their cousin left and tells the protagonist to be nice to them.

Mettaton

Undyne does not know that Mettaton is Napstablook's cousin. She has a distaste for him, and she does not like his show. Though she does acknowledge that she "admires his lifestyle."

Shyren

Undyne used to give her piano lessons, but one day she stopped coming – probably after fell down.

Alphys

Ummm...
H-h-hiya!
I'm Dr. Alphys.
I'm ASGORE's royal scientist!— AlphysContents[]

Dr. Alphys ( AL-feez, AL-fis) is a female, reptilian that lives in the in western . She is the incumbent Royal Scientist, a position she was awarded by after the death of . Asgore hired Alphys because she told him that she had created a ; in reality, she created a robotic body for .

ProfileAppearance

Alphys is a yellow, reptilian monster of similar height to the protagonist. She has scales, round glasses, protruding teeth (which seem to vary between two and three depending which way she faces), and normally wears a white lab coat. However, she wears a polka dot dress on her date with the protagonist.

Personality

Alphys is a nerdy, shy recluse with a fondness for anime and manga. She has crushes on multiple characters (some mild, others more serious), but struggles to communicate her feelings.

Alphys is filled with guilt and insecurities about herself and her accomplishments. After she accidentally created the while experimenting with , she told nobody and became depressed.

Main Story

Before the events of Undertale, Undyne met Alphys in the , where Alphys was deep in thought. Alphys accidentally created the Amalgamates through experiments with Determination sometime before the protagonist falls into the Underground.

Actually, wait, I have an idea!
Let's be friends on UnderNet!— Alphys

The protagonist's first encounter with Alphys.

Alphys initially meets the protagonist in her lab. She explains that she has watched the protagonist throughout their journey using hidden cameras and adds that she wants to help guide the protagonist through Hotland.

Alphys explains that a robot she created, Mettaton, wants to kill the protagonist. Mettaton then bursts the wall and forces the protagonist into a quiz show; Alphys helps the protagonist by signing the letter of the correct answer with her hands. Mettaton catches on after Alphys excitedly answers a question about her favorite video game, and Mettaton embarrasses Alphys by asking the protagonist who they think Alphys has a crush on.

After Mettaton's quiz finishes and he flies away, Alphys offers her phone number to the protagonist. She notices that their is old and quickly upgrades it with features including texting, a key chain, links to two , and access to the . Alphys explains these upgrades and rushes into her lab's "bathroom."

As the protagonist progresses through Hotland, Alphys frequently updates her UnderNet status. She calls to help the protagonist with puzzles but dislikes to give them the solutions outright. Alphys stops posting status updates when she realizes that the protagonist has been reading them the whole time.

Mettaton antagonizes the protagonist in several deathtraps, but Alphys informs the protagonist of a phone upgrade to aid them in every situation. If the protagonist fails any of Mettaton's challenges, Alphys blames herself, and Mettaton helps her out by letting the protagonist go. Alternatively, Alphys takes some credit if the protagonist succeeds.

Alphys attempts to guide the protagonist through the but struggles doing so because of the CORE's ever-changing layout. If the protagonist follows her instructions, they often hostile monsters. If the protagonist does not follow her directions, she worries about their trust in her.

At the end of the CORE, Mettaton reveals that Alphys inserted herself into the protagonist's journey by creating obstacles for them to overcome together. While she is locked outside, Alphys instructs the protagonist to turn Mettaton around and flip his switch, making him vulnerable. After the fight, Alphys unlocks the door and looks at Mettaton's body. If the protagonist spared Mettaton, Alphys is relieved that he just ran out of battery power. If the protagonist killed Mettaton, Alphys pauses and slowly reassures them not to worry. She stays with Mettaton's body as the protagonist progresses into the next room.

Alphys catches up with the protagonist before they take the elevator to . She admits that she lied to the protagonist, and that the protagonist will have to kill Asgore to pass through the . She then leaves.

NGAHHHH!!! NGAHHH!!!!
I'M UNDYNE AND I'M PILING ON THE SMOOCHES!!!— Alphys roleplaying as Undyne

Undyne tosses Alphys into a trash can during the date.

After the protagonist delivers to Alphys, Alphys reluctantly goes on a date with the protagonist because she thinks that they wrote the letter. She changes into a dress and takes the protagonist to the Garbage Dump for their date.

While there, the protagonist and Alphys roleplay to help Alphys open up to Undyne about her feelings. Undyne overhears them talking about her and approaches. Alphys confesses that she was trying to impress Undyne by making her hobbies sound more scientific, and takes Alphys out for a lesson in self-confidence. Their training ends early and he sends her home.

Come on, guys.
It's time for everyone to go home.— Alphys, speaking to the Amalgamates

Alphys's note in front of the True Lab's entrance.

When the protagonist returns to the lab, a note from Alphys lays on the ground in front of the "bathroom." The note directs the protagonist to the True Lab's entrance to discover the truth, in case they do not hear from her again.

The protagonist learns about Alphys's Determination experiments in the True Lab via consoles on the walls that have her lab entries on them. She isolated determination from the and injected it into monsters who had "fallen down" in an attempt to extend the longevity of their SOULs after death. None of the monsters died, and they were well for a short time before they melted together.

Alphys's lab entries explain that monsters lack the physicality that humans have, and that this is why the monsters fused together; their bodies could not handle high concentrations of determination. She did not tell anyone about the Amalgamates and feared hurting everyone's feelings.

As the protagonist reaches the power generator, Amalgamates approach and trap them. Alphys stops the Amalgamates and explains that they were "sassy" because they were hungry. Alphys then tells the protagonist that she had a change of heart and will tell everyone about her failed experimentation.

She then leaves the lab and returns the Amalgamates to their families.

Alphys also joins Undyne in breaking up the fight between Asgore and the protagonist. Alphys is surprised to see two , and comforts Asgore after rejects his bid of friendship. Mettaton prompts the two to kiss, but Toriel interrupts them from doing so.

Flowey ensnares Alphys along with the protagonist's other friends.

Alphys questions how Papyrus knew to call everyone to New Home, and appears alarmed when Papyrus informs her that "A TINY FLOWER HELPED ME."

After ensnares the protagonist's friends, Alphys encourages the protagonist by stating her faith in them. Flowey absorbs her SOUL along with the SOUL of every monster in the Underground.

Alphys appears as a during .

Epilogue

After Alphys regains consciousness, she remembers little about what happened. She tells Asgore and Toriel about her failed experimentation; Toriel fires her.

After the protagonist wakes up, she discusses her plans to watch anime when they leave for the .She also helps explain what anime is to Asgore, and asks for 's help in doing so. Alphys tries to show Asgore anime on her phone but accidentally shows him a picture of robots kissing.

On the Surface, Alphys joins Undyne, who leaves to check on Papyrus. In the , Alphys relaxes on the beach with Undyne, , , the , and . Undyne kisses her on the cheek, and she faints.

After Undyne calls her, Alphys evacuates monsters in Hotland to the True Lab. However, a few monsters remain, including and . She does not confront the protagonist directly.

Relationships

Before the events of , Mettaton (as a ghost) started a Human Fanclub. The only person who joined was Alphys, who showed Mettaton designs of a robot she wanted to build for him.

Alphys worries that Mettaton will leave her behind after she finishes his body. She cares deeply about Mettaton, and would not know what to do if he was gone.

Alphys disappears in Neutral Route endings where the protagonist killed either Mettaton or Undyne; it is hinted that she may have committed suicide.

Alphys has a crush on Undyne, but Alphys fears Undyne finding out the truth if she confesses her feelings. Alphys tries to impress Undyne because she does not want Undyne to think that she is a nerdy loser. She also names variables after Undyne, writes her name in the margins of her notes, and writes fictions about them sharing a domestic life.

Alphys shares her love of human anime and manga with Undyne, though Alphys convinces Undyne that anime and manga are actual depictions of human history.

Together, they hang out at Alphys's lab, where Alphys makes "chilly pink stuff" for Undyne. Alphys also helped Undyne create some of .

On a True Pacifist Route, Alphys and Undyne begin dating, and, in the True Pacifist Ending Credits, Alphys faints after Undyne kisses her on the cheek.

Guiding you has made me feel...
A lot better about myself.
So... thanks for letting me help you.— Alphys

Alphys admires and supports the protagonist as they adventure through the Underground. She watches them via hidden cameras from the moment they leave the . She attempts to insert herself into the protagonist's journey by creating obstacles in Hotland, but she later admits that this was just an attempt to make herself feel better.

She dates the protagonist because she believes that the protagonist wrote Undyne's love letter; Alphys later admits that she has no interest in actually dating the protagonist and was only pretending to go on a date to be nice.

If the protagonist aborts a Genocide Route in Hotland, however, Alphys holds no positive feelings for the protagonist and says that she should have killed them when she had the chance.

Alphys works for Asgore as the Royal Scientist. She lies to Asgore about creating a SOUL and presents Mettaton as proof of her achievement in an attempt to impress Asgore.

She tries to do what Asgore asks of her, which leads to the failure of the determination experiments.

Alphys has a crush on Asgore and sometimes refers to him as "Mr. Dreamy." In the epilogue, Alphys comments that she has moved on from Asgore, and adds that she thinks Asgore and Toriel are a cute couple.

Alphys did not know about Toriel until Alphys met her while interrupting Asgore's fight with the protagonist. Even though Toriel fires her as Royal Scientist, Alphys easily befriends Toriel. Alphys also finds her attractive.

When Toriel questions how anyone could flirt with her, Alphys laughs hysterically. This is a likely reference to the positive fan reception of Toriel after the . Alphys also expresses her love of the "Tori and Gorey" ship, adding that she may write a lot of fanfiction about it.

Alphys used to live on their street. She was like a big sister to them and took them on trips to the Garbage Dump to find cool junk. They reveal that Alphys made Mettaton to impress Asgore, and add that no one has seen Alphys recently.

Alphys evacuates Bratty and Catty on a Genocide Route.