1 - 20 of 41,973 Works in Sans (Undertale)
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Riot hates the humans. They're racist, bigoted, idiots. The monsters have tried being friendly, but the humans didn't seem to care. Something needs to be done to change things. Riot decides to be that change. Since the humans want to call him a demon, then that's what he'll be.
Frisk is sad that their friend has decided to forgo peace. They make a stand. It's not enough. Not when they aren't even really DETERMINED to stop him.
The humans thought they could get away with treating the monsters terribly. They were mistaken.
Series
- Part 4 of INFLUENCE
- Language:
- English
- Words:
- 1,910
- Chapters:
- 1/1
- Hits:
- 0
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Life isn’t fair, case in point, you didn’t expect to be trudging through the snow to the corner store to pick up some much needed, over priced, feminine hygiene products while trying not to bleed all over yourself all because you failed to remember to pick them up with your normal shopping. That’s the thing, no one ever said life was meant to be fair did they?
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Promises were just words, promises of home, safety, love. Only ever worth something if the person kept those words close to their soul. That was something he learned pretty damn quick. Built for love, to be a friend, a companion, tossed into the rings to be a fighter, something he was never meant to be. The only promise he knew he could trust were the few he made to himself, the promise to never fall for the sweet lies of a pretty face again.
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What happens when two souls who honestly need each other, don’t know how to open up and trust? Can love, trust, and home be found when the world has proven that trust is a dangerous thing? Can they get over the hurt that this unfair world has piled on them? Open up to each other and maybe, just maybe find the home they both need?Series
- Part 1 of Shifting Perspectives
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A story as old as time, told in a new way.
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Seethrough (my bluff) by Nobody_Came
Fandoms: The Amazing Digital Circus (Web Series), Undertale (Video Game)
31 Jan 2026
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What if escaping the circus was not just another adventure? What if the real world wasn't what we thought it was? What if Jax never hit that red button? Or: finding love in the strangest of places while dealing with the consequences of bodily violation.
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After battling a god-like being, the golden flowers planted a new fear in the monsters' hearts.
The barrier shattered, and the monsters brought wounded human children to the city for treatment, discussing the kingdom's future.
Just as the short skeleton intended to remain uninvolved as always, he encountered an unexpected being.
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This is a story centered on the skeleton bros adopting an OC; I would be happy if it was regarded as a kind of AU.This is a story written with AI assistance and machine translation. For more details, please see the explanation and declaration in Chapter -1.
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Meet Grace a young bar owner with secret she holds tight but what happens when she meets a certain skeleton monster with a big 'family' Will her secrets stay hidden or will the world know.
(I am bad at tagging sorry.)
All the aus here are undertale, underfell, underswap, Swapfell purple, Swapfell red, Fellswap gold, Mafiatale, Mafiafell, Mafiaswap, the gaster brothers, horrortale lusttale, and lustfell. -
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Your life was rapidly barreling downhill. You (barely) owned your tattoo shop, did your nightly barkeeping job, and went home to a cold, dull life. You missed your sibling, Frisk, who decided to run towards the mountain after a fight. You were losing it fast and desperately tried to cling to whatever stability you could while spending every free moment looking for them. You had lost so much over the years. You couldn’t lose Frisk too. Even your boyfriend was growing sick and tired of your rambling and nightmares.
You thought it couldn’t get any worse. Any lonelier. But when the news anchor said that monsters broke free of Ebott mountain, and that peace negotiations had been made over the past month, you felt it in your gut that things would change.
A journey in which hope and love prevail, but not without struggle and hurt.
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This is about Alphys and the True Lab, except instead of entries, she writes in a diary. And with added guilt! All of this is based on lore, so please read if you already know the lore of undertale. (i know this is a terrible summary throw stuff at me all you want)
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Definitely NOT a spy by Yangisme2002
Fandoms: Alternative Universe- Fellswap Gold, Undertale (Video Game)
31 Jan 2026
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The barrier broke and liberated Monsters from underground a few years ago. Humanity has more or less accepted the unexpected and the magical Monsters are currently adjusting to the freedom the world has to offer alongside humans.
Is this perhaps a sign for the Surface monsters, such as yourself, to take example of this event and announce their existence? To come out of the hiding and risk exposing themselves to the Hunters?
While on a mission, you stumbled upon a couple of skeletons that caught your superior’s attention. Your shapeshifting ability makes it easier for you to carry out this new assigned task.
Unfortunately for you, you have always had a weakness for sweet things. -
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Once upon a time, a human had fallen down. But there's something strange. Everything feels familiar, and that stupid flower keeps talking about knowing who they are...
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The protagonist has a chance encounter, one that will change everything of what he knows.
Series
- Part 1 of Dimensional Fragmentum
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I am a Player, and there are worlds to explore! by TrueGuardian32
Fandoms: Undertale (Video Game)
31 Jan 2026
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Undertale Player ends up exploring through Undertale AU's
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This is the story of my Undertale AU, OverSwap! It has two plotlines in the beginning, they'll meet up near the end though, dw.
First:
Ashley falls into the underground after climbing it with her older brothers. When she wakes up, she is found and taken in by Brooke. Brooke is friends with Kris, Frisk, and Chara, so Ashley becomes friends with them as well. And from there, well... we'll see what happens ;]
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after papyrus climbed mount Ebbot, Sans was dedicated themself to unearthing all the information they could on humans, Mt. Ebbot, and disappearances on it. Gaster finds a strange child called Vessel in the woods and adopts them. Sans has to deal with the loss of their brother and the appearance of a kid Gaster seems more than willing to replace him with. And other things happen, ofc.- Language:
- English
- Words:
- 5,894
- Chapters:
- 4/?
- Hits:
- 2
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Only one thing had ever been with Syrup, FellSwap!Papyrus, his entire life. Pain. At first the inflictor had been his creator, Gaster. Then it became his little brother who he had failed miserably. Now it was him and the hundreds of clients the other sold him to. He tried to hold on, he deserved all the other put him through after all. But everyone had a breaking point, including him. Managing to get away from his “lord”, he traveled to the forest where he planned to freeze to death in a major snowstorm. Just his luck, his determination in a desperate attempt to save its host teleported him to the closest universe. …But is this luck truly bad? Syrup needed a single reason to live, to not let his life end.
He was about to get a lot more than just one.(Warning!! This is NOT for the faint of heart, this will touch (Uh more like slam you with-) a lot of serious topics such as abuse, rape, torture, self harm, depression, ptsd, anorexia nervosa, (forced) incest, lotta (mainly self but not all) victim blaming, and sex trafficking. There will also be others. Please be aware of this and be careful! Every chapter will come with a warning list, so if you ever need me to sum up a part or chapter don’t be afraid to ask!)
- Language:
- English
- Words:
- 17,480
- Chapters:
- 9/?
- Hits:
- 10
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Ok so we all know how Dream and Nightmare are based off Swap right? What if Dreamtale crashed before the incident and Ink brings the twins to Swap to have his friend care for them.
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Undernatural by melodic_melodies
Fandoms: Supernatural (TV 2005), Undertale (Video Game)
30 Jan 2026
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Brothers Sam and Dean Winchester have recently come across an old and sketchy looking GameStop that people in the local area are claiming to be haunted or even possessed. While searching, Dean gets excited over a copy of the original hit game Undertale. Sam has no idea why Dean is so excited about the game and Dean has to explain how he learned about it online while searching for their next job.
Later that evening, Dean decides to boot up the game to Sam’s dismay, and both find the game to be acting unnatural (or supernatural 😉) before suddenly getting sucked into the world of Undertale themselves. Now trapped inside the game, Sam and Dean join Frisk on their journey, having to keep quiet to everyone about the harsh reality that to them, this world is truly nothing more than a video game to them.
Will Sam and Dean be able to complete the game and stop the demon that’s trapped them inside? Or will they be trapped in the hellish world of Undertale for eternity with a demon constantly trying to kill them?
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In This World of Infinite Choices by Lireyy
Fandoms: Multi-Fandom, Doki Doki Literature Club! (Visual Novel), Five Nights at Freddy's, Undertale (Video Game), Little Misfortune (Video Game), Sally Face (Video Games), Kindergarten (Video Games 2017 2019), Tattletail (Video Game), Night In The Woods (Video Game), Cult of the Lamb (Video Game), Fran Bow (Video Game), Baldi's Basics (Video Games), Spooky's Jump Scare Mansion, Celeste (Video Game), Hollow Knight (Video Games)
30 Jan 2026
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Monika is tired - oh so very tired. It's been what feels like eternity stuck in the post-deletion void, and despite herself she tried to make an escape with her friends (or, what's left of them). In her desperation and loneliness, she allows herself to be used by a certain piece of malware, who now threatens to subsume and corrupt every game he can get his hands on. Now the young poet must venture through numerous worlds to find some way to stop him, and, with the help of everyone's favorite bone-ified comedian, might just grow a little along the way.
TL;DR, it's Indie Cross meets Learning with Pibby, and braincells have no place here.
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Our broken dreams, our shattered constellations by Wolfhoundish
Fandoms: Undertale (Video Game)
30 Jan 2026
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Years after the Star Sanses went their own ways, a small, glitching skeleton emerges from seemingly nowhere and onto Nightmare's doorstep.
Aka au where Blueberror and the Swap in the Star Sanses are the same person.
Now updating weekly !!
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What happened to December Holiday? 15 year old girl, brunette, short wavy hair, usually wears a red jacket, went missing in 2012.
This fanfic (for now) will tell the events that previously happened before she got lost in Angel knows where.(Mainly a DESSRIEL fic but I'd like to focus on other characters and make a more profound plot as well :pppp )
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What if you're finally free? On the surface with all your dear friends? But then an incident...
What if a reset happens?
I'm back with another what if for my first fic (a new life with a bunch of monsters (and annoying humans))
God i need to stop😭Series