1 - 20 of 26 Works in Waterfall Residents (Undertale)
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“it’s just…you keep acting like something horrible is waiting for you at the bottom of this mountain.” His whispered voice was calculated and obnoxiously observant.
Frisk chewed their lip and felt their nails subconsciously start digging into their palm. The last thing they wanted to do was ruin anyone’s excitement about the surface with their own anxieties. If anything, they thought they’d been hiding their fears pretty damn well.
“There are some things, Sans…” their voice seemed to start against their will, hushed and constricted. They put a hand over their heart, which was beating restlessly.
“…that I just can’t explain to you,” Frisk finished exasperatedly.
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Nathaniel Walker was an ordinary man who worked as a construction worker to support his elderly parents, but unfortunately met a sudden end during an accident at work. Upon awakening in what he assumed to be limbo, his regrets and attachment to his life keep him from passing on yet unable to go back since no one could undo death. In the end, the void takes his soul and he fades into nothing.
...Only for him to wake up in an underground lab, confused and afraid, while questioning why he's a skeleton... and a child at that.
Nathan has never heard of Undertale, so he's experiencing this world for the first time, unaware that his mere presence has a drastic change on the story you might be familiar with. Regardless, his goal eventually aligns with all of monsterkind, which is to reach the surface so that he may try and find his family again. However he may just find a new family while he's down there.
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A FINE LINE BETWEEN ORANGE AND YELLOW - Hiatus/Rewriting by MairwynCSulien1990
Fandoms: Undertale (Video Game), Original Work
07 Nov 2025
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While Aneira didn't necessarily believe monsters existed, she did find the fact that everyone and their dog still did might mean something. Her childhood town of Beddgelert believed in monsters trapped under the mountains near their home that would need a seventh soul now to break out and destroy lands.
Putting this on hiatus because not only do I feel I can characterise Aneira better (writing characters in character is not easy for me), the general plot can do with reworking and yk foreshadowing. Might just reupload chapters once I've completed the story, which may actually get me to update something in a reasonable time frame.
Do not expect anything to be done soon because I am going to be very busy very soon and won't have the time until the Christmas holidays.
Sorry, not sorry, I want something I write not to weigh on my mind how badly written it was, less so than usual - this note is mainly for the singular friend that follows me and may actually read this.Series
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Nine strangers. One fall. A power none of them understand.
When eight teens and a young girl follow a mysterious light into Mount Ebott, they expect adventure. What they find is a crumbling underground world of monsters, magic, and ancient conflict. But that’s not the strangest part.
Each of them awakens with a glowing SOUL—a trait linked to their heart, their will, their essence. But these SOULs don’t stay still. They shift. Swap. Sync. And with every battle, their bond grows stronger… or more dangerous.
As they struggle to understand this new power, they’ll face old threats, cryptic warnings from a familiar talking flower, and a world that remembers the war they never fought.
They just wanted answers. Now, they’re part of something much bigger—and something down here is watching.
Welcome to the Underground. Stay determined… or get creative.
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Things Change.
Stuff Happens.
Life Goes On.To describe to you what happens is a spoiler in itself. But I will say, it will all be worth it in the long run. Bloodshed, fallen allies, family reunions, first loves, first hardships… false memories.
In the end, everything will make sense.Word count: 24,424
Started: 08/27/25
End:
© Reserved and Created Originally by: Honey -
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A few years after everything is over with Vecna, Steve and Robin decide to take a vacation to live life a little. They end up back in another convoluted scenario that only their luck could bring upon them.
They've fallen into another world where monsters lived (which, this wasn’t even the first time!). Now, they've got to either figure out a way out or settle into life in this new place, all while dealing with a mystery involving their souls.
Steve blinked, and the whole world changed. Everything seemed grayer, suddenly, and there was a single heart floating in front of him and Robin.
The flower’s face dropped. “What the fuck? I swear I pulled both of you into the encounter.”
“What does that even mean?” Steve asked incredulously, bat quickly back to being raised in front of them.
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I Will Take Your SOUL and Break Your Heart by i_never_ate_raindrop_cake_but_i_want_to
Fandoms: Undertale (Video Game)
22 Aug 2025
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A story that narrates the adventure of a young woman and her new Human — but also Monster! — friends. She wants to be able to give everyone the Happy Ending they all so crave.
They need help in ending this Sorry Tale before it is too late.
ᯓ★
He asked you why you betrayed him. His breathing was ragged, and his hair did not have the same pleasant odor of coconut oil and wheat that you had grown to love. It was musty, reminding yourself what kind of monster you had in front of you.
Not a Monster, but a monster.
The meaning of his name didn't carry his personality anymore.
"... Ironic, is it not? Since I am not the one who is holding a dusty knife right now."
Series
- Part 1 of Petrichor
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It's been 10 years since Mettaton took over the Underground. Anne, a 15 year old girl, falls down after trying to check if a message she hears in an old phone she finds is real. Anne arrives at the Underground, oblivious to the dangers in the kingdom, except for bits of information from the message. Throughout her journey, Anne discovers the truth about the Underground with the help of other monsters and she also discovers some things about herself.
Royal Bullet's plot extends parts of Undertale's canon plot, and contains some headcanons of mine.
Special thanks to my beta reader, thelegendofmudkip: https://thelegendofmudkip.tumblr.com/
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It's 1935 and Myth's whole life has been nothing but hell under the heels of the Ebott Dusters Mafia. A plan is set, she and those she cares for are making a run for it, hoping to start a new life in the monster capital of the world, Omega City.
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An introverted and anxious person wakes up as Sans and has to try and not rise suspicion. (I don't know im bored and this idea just came up)
Im testing some stuff with this one
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While taking a walk with your cat, trickles of rain turn into a heavy downpour, forcing you to take shelter in a cave. You lose your cat in the darkness, and in a desperate attempt to find her, you slip and fall into the depths of the Underground. Can you and your cat survive the harsh elements, as well as the monsters of a lost race? Perhaps... things aren't so bad down here.
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hi
umhad an idea to make a fun little series where frisk is a cat
was going to be just frisk at first but on a whim I just added reader as well as made the plotline a bit darker
this is my first official work on ao3, but I have ideas for other works if this idea falls through or I just get bored of it
anyways feel free to leave tips or anything in the comments if u somehow find this series
enjoy <3
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Of course this happened, to me of all people. When I was simply minding my own business and reading some of the good old fanfiction I just HAD to fall asleep and find myself in the damned game itself. And you should know that falling is NOT as peaceful as it is in those movies.
When an angsty teenager who has nothing better to do in life suddenly gets yeeted into the fictional (and slightly aware) world of Undertale, what else could you expect them to do other then to walk through this game once more in their gen-z way?
Inspired by "Great, Another Self-insert Fic" by Hyuuint which could be found on Archive of Our Own, None of the characters except for the one that the MC talks to in the Prologue belongs to me.
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Life in the big city was more than you ever imagined; So much traffic, hoards of people and monsters, and Mafias running rampant in the streets! Did I mention the traffic?
Let's not forget about how you accidentally stumble upon a monster-only speakeasy and into the arms of danger.
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UNDERFELL: Tale of a Fallen World. by ElenArtsy
Fandoms: Undertale (Video Game), Underfell- fandom
10 Feb 2024
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(An Underfell illustrated story by ElenArtsy.)
This story is about Frisk's journey through a destroyed and hateful Underground in which they are not welcome. As they struggle to survive the many enemies on their way, they are forced to witness the tragic consequences of the Tyrant's long dictatorship over the citizens' souls and minds... The rules are strict in this merciless world: it's Kill or Be Killed. Will the young human be able to change to fit and survive this cruel reality? Or will they give in to the unstoppable circle of violence?
Based on the comic Underfell by me. (https://www.deviantart.com/elenartsy/art/Underfell-Intro-1-3-A-long-long-time-ago-816753512) You can also read the story and find all of its illustrations on my DeviantArt profile.
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CotLtale by Nekozaburo
Fandoms: Undertale (Video Game), Sky: Children of the Light (Video Game)
11 Apr 2023
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(Undertale and Sky: CotL crossover AU)
*Eye of Eden, all sky kids must go through it once in their life.
*But something went terribly wrong.
*Sky kids weren't returning from Eden, and no new children fell from the stars.
*No one wanted to believe it, but it must be true.
*Megabird had died.
*Years passed.
*Eden suddenly erupted.
*Raining down parts of its corrupted world, sky kids scrambled to get rid of it before they spread.
*But, they weren't enough of them to get rid of the corruption, and it spread more and more.
*Now, sky kids have lost their light.
*With no reincarnation or new life, there was no point to fight against the darkness.
*Decades later...
*A kid found themselves on the top of Eden, and fell down a hole... -
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The barrier is gone but on the way to the ruins, Asriel visits an old spot.
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Chara doesn't understand why their world doesn't feel like it belongs to them, why they don't feel real.
They hope climbing the mountain might give them answers.
(They don't like what they find.)
Series
- Part 1 of PARENTHESIS
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Luck didn't favor me that one night. I didn't just lose my job, I also had been a witness. The Bakery. The same place I loved working at, was burned down that night. I was still inside when it happened. The Mafia who ran my city came to collect the "protection" fee that night. The elderly couple who ran the place couldn't pay up. The collector wasn't amused, so he had his men make an example out of them. He killed them. He thought It be hilarious if he were to burn the place down. So he had done exactly that. I managed to escape through the backdoor, but it was all for naught. I was standing in an alleyway, surrounded my bulky men. They probably knew I was inside and had been waiting for me there the entire time. I thought they'd kill me on the spot, but they didn't. They had something far worse in stored for me. "We can't have a witness, now can we?" One man said. So they took me the mountain. I tried screaming for help, but nobody heard. When we arrived at the mountain, they didn't even hesitate pushing me in. It was a long fall down. I thought I had already died and was just reliving the experience again. At some point, I finally made it to the bottom. And that's how my adventure began.
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It was hard to tell when the pain had stopped and when her withering form had finally ceased to move unconsciously within the arms of the man who had promised her sanctuary. It was a cruel punishment for the man himself to witness; after all, she was the one who promised him the world; little did he know, she had meant that quite literally rather than figuratively.
Updates every Friday (Hopefully)
Series
- Part 1 of Ready Or Not Series
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Arcana and Daniel, the power duo set on bringing life to their new pack. However, when they're thrown into the Underground by a rival pack, they have to learn and adapt.
Things don't go as planned as they meet various demons of the underground, battling against the odds and fighting for their survival.
Survival is at stake, but what's the price? Their home? Their pack? Their lives, even?
As the bones of the dead come to life and blood mixes with magic, anomalies and accidents will happen to make monsters of blood and magic.