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The Games We Play by FoundUser, Primordial_Rebel_Jester
Fandoms: Deltarune (Video Game), Undertale (Video Game)
02 Sep 2025
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Summary
There are infinite opportunities in this world. Infinite opportunities for dreams. Infinite opportunities for hopes. Infinite opportunities for regrets... for loss.
There are some memories you would rather just forget...
The old royal scientist knew that better than anyone.
BRIGHT, BRIGHTER, YET BRIGHTER. SO YOU STILL SHINE ON, EVEN AFTER EVERYTHING YOU ENDURED. EVEN THROUGH THE COLDEST NIGHT.
But a story doesn't have to end the same way.
EXCELLENT. TRULY, EXCELLENT. LET US BEGIN THE CREATION OF OUR NEW FUTURE.
Sometimes... a game can have a secret ending.
(A Deltarune novelization that takes some unexpected turns from canon. Based on some theories, and a little bit of imagination, even the unknown can make itself known.)
(Custom Art and beta'd by Primordial_Rebel_Jester. Story by FoundUser.)
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Kris has long lived an oppressive life: First shoved under the thumb of Carol, and more recently placed in the clutches of the SOUL. Fearing to further derange the situation, they bitterly stay in line. That is until a strange book is discovered at the back of the Librarby's second floor.
With new-found determination, they set out to take revenge. And along their journey, increasingly disturbing happenings haunt them and others. Perhaps it has already started?
Will Kris manage to restore balance to the world, or will they die trying? Is it already doomed? And who is the strange voice you keep hearing?
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Gather children, listen well, harken to the Under Tale.
A story of a small child, falling into a massive cavern where monsters have made their home. With the help of a certain phantom, the child makes their way through the Underground, making friends & family along the way.
I own absolutely nothing in this. Undertale, along with with characters, setting, etc., belong to its respective owners, who are not me.
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After noting the odd feelings they'd both been having, Kris and Susie meet at the lake and end up discussing them.
Series
- Part 3 of Krusie fanfiction
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Under(her)tail Genocide Route by Asra_the_33rd_TeaEnthusiast
Fandoms: Undertale (Video Game)
18 Jul 2025
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This is my interpretation of a full "Genocide" Route of the Under(her)tail comic by TheWill. Read the tags. This is gonna be one fucked up, vulgar-ass story.
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A side story of handplates by Autistimweirdo
Fandoms: Undertale (Video Game), Handplates - Fandom
11 Jul 2025
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Telila had never really did anything remarkable as a scientist and she knew it, she wanted to be seen as a one and not just the coworker of alphys and gaster. She had been trying to be more useful to society in the underground by fixing more stuff, discovering new stuff or even making new things. But the underground had a bigger concern, the barrier. She noticed that her efforts were less and less acknowledged, that her friend Gaster acted distant and that the king seemed more distracted... Then a question appeared in her head, it lingered and made it almost impossible for Telila to think about something else: could she make a nonhuman soul strong enough to break the barrier? After a few tests and studies she came to the conclusion that she could, by taking any kind of fragment of a soul and fuze it with another weaker soul and in this case an animal soul's, it would make it strong enough to count as another human soul and break the barrier. she didn't want to take the soul of another monster to strengthen the weaker soul and she didn't want to take only hers either, it could harm or even worse, shatter the soul of the monster. But with a little help from one of the human soul she wouldn't even have to sacrifice her soul.
- Language:
- English
- Words:
- 416
- Chapters:
- 1/?
- Kudos:
- 1
- Hits:
- 4
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DELTARUNE: Threads of the Soul by nim_ko
Fandoms: Deltarune (Video Game), Undertale (Video Game)
04 Mar 2025
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They really should get along better.
I sure hope this doesn't result in magical hijinks, extreme levels of action movie violence, and a traumatic introspective of these characters as people! That would really be a shame, I think. They live such peaceful lives, or whatever.This story functions as a custom connection between UNDERTALE and DELTARUNE, mostly through time and character consistencies. Basically, Frisk is real and also very dead from old age.
Reasoning for the "Slow To Update" tag: I've been in the midst of a rewrite of the first chapters, because I realized I cared a little bit more about the story than what I presented quality-wise. Once this is finished, things should pick up again. It's just difficult choosing between which elements to keep and which ones to throw.
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Pirates Of The Undertale by Cat_On_A_Keyboard
Fandoms: Undertale (Video Game), Pirates of the Caribbean (Movies)
16 Feb 2025
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Pirates of the Caribbean reimagined as Undertale characters. Currently in development, this is a rough write up of character substitutions and plot ideas. Looking for co-writers/proofreaders if anyone is interested in helping.
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Seventh - A Prologue (Undertale AU - Mirrored Edge) by JacketOfDiamonds
Fandoms: Undertale (Video Game)
31 Dec 2024
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In a world characterized by grim reflections, one Royal Knight has a difficult day. But then again, he doesn't have the worst of it.
Warning for fairly canon-typical involvement of child death and suicide, brief implication of parental figure death, and mildly unsanitary activity (Jerry).
Series
- Part 1 of Mirrored Edge
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A town called Hometown is named home to all, but what lies beyond the humble fall? Here lies a legend too old to sell, a world that crosses both heaven and hell.
A short Deltarune story based on the Lemon Demon EP "I Am Become Christmas."
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Undertale But All of the Characters Are Cartoon Villains by Socrates_the_MudWing
Fandoms: Undertale (Video Game)
18 Nov 2024
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I woke up one day and said to myself, "Self, there just aren't enough Undertale AUs out there. You should create one." So I did.
Hopefully things will still be more or less recognizable in this one, since I'm sticking relatively close to the canon plot. Well, kind of. I'm keeping the part where Frisk falls down a hole, wanders through the Underground (now the Underdark) one zone at a time, and eventually fights Asgore. That's pretty similar.
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Monsters have been freed from the underground. With this freedom, they can finally live on the surface. But things were never going to be easy.
You are an average human living in a crappy apartment building with a shitty landlord. No family, few friends, and a cat you love very much. But these new monsters moving into your building might just be the best thing to ever happen to you.
Oh yeah...and the skeleton across the hall is really cool, too.
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Searching for ways to cross the barrier, Chara decides to make some use of her brother.
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After an ancient meteorite crashed down in the waters beside Hometown, weird things started to happen. Most of Hometown grew hornier, yet hornier, and Hometown was split into two divisions; those that embraced the new horny nature, and those that tried to cling to the way things were before.
That was three years ago. Now, in the present, we get to watch just how this meteorite has affected the heroes story, and what it will mean for the future of both the Light World, and the Dark World...
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The Underground was ravaged by a pointless, spontaneous massacre, and those few who survived emerged into a world of uncertainty and fear. While order was restored, freedom and decency were lost, and the situation only intensified with time.
Now, an interloper has appeared, with a manipulative nature and serving unknown causes. In his eyes, he must succeed at his goals and will do anything to persevere. To the others, his existence may drag ugly secrets to light, spark a rebellion, or end their lives.
Yet, beneath all of this, someone else has been watching, waiting, and everything, no matter how unpredictable...
Has all gone exactly according to plan.
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Hello. I hope you enjoy this. It's going to be rather esoteric and unorthodox. I wanted to go out on a strange limb with this and I feel like I've succeeded. Please leave a comment if you have any thoughts on this work at all.Thank you for your patronage.
-BFA.
Vote on your favorite character here: https://strawpoll.com/poy9WlLa3gJ
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For a more conventional fanfiction, please consider this Alphys-centric work here: https://archiveofourown.org/works/51642697Series
- Part 5 of BFA's Undertale Stuff
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It's Underfell's turn!
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- Part 2 of My Child
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John Smyth, a 17-year old Computer Science professor at the University of [REDACTED], likes writing fanfiction. Currently, he's been fixated on a game called Deltarune and has accordingly been working on a Deltarune fanfiction. After one of his classes discovers his writings, he rushes to polish them before his writings further embarrass him. But exhaustion sets in, and he ends up asleep at his desk. When he awakes, he is met with the world of Deltarune and an adventure he is more than hesitant to go on. He will face great challenges throughout an increasingly connected multiverse, from false worlds, dark worlds, Dess Holiday, the Human Monster War, and a mind-control prison to void creatures, hidden backstories, Hell, and even a material that can reverse death itself. But the greatest challenge he has to face isn't any of those. It's himself.
To meet your favorite fanfic authors, like Sophtopus, TimeCloneMike, or Dorked, and of course, me, join the Fanfic Paradise Discord Server at https://discord.gg/TD2DJzbgWn
If you like (or dislike) the story, please let me know! It'd mean a lot to me!
BEING REWRITTEN AS RE:CONNECTED.
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Rank: Determined Survivor by Veloo
Fandoms: Henry Stickmin Series (Video Games), Undertale (Video Game)
30 Apr 2023
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After Triple Threat, Ellie decides to have a vacation, Charles gets a break, and Henry? Henry's bored. Without his friends, there's not much to do. He needs some more adventures in his life! But what should he do? How about climb that mountain that nobody returns from? Sure, why not?
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Derringer is the queen's Enforcer, but not by choice; the Underground is underneath a tyrant's thumb and no one seems to be able to defy her except him... and even then it has led to his personal suffering as he tries his best to stay between the tyrant and the innocent monsters she wants to dust for her own amusement or stupid whims. He knows that he cannot keep up this forever and his brother, second to Captain Alphys of the Royal Guard, could be left on his own if ever the tyrant had reason to dust him. One day, while on his way back from the usual day in court, he comes upon a strange monster in need of help ...
Series
- Part 2 of Fellswitch: Fate
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Kris goes to great lengths for Susie's heart, but this time he's gone too far.