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I am a Player, and there are worlds to explore! by TrueGuardian32
Fandoms: Undertale (Video Game)
07 Mar 2026
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Undertale Player ends up exploring through Undertale AU's
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You wake in a strange room and the only thing you can register is the overwhelming amount of magic that saturates the air. You can barely sense your brother and the strangers standing over him.
...wait a second.
Series
- Part 1 of That Damn Machine
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You were a normal human. You went to college, you had a life, friends, family, etc. Apparently, the void didn’t care much for happy endings, and you find yourself strapped to a table in an underground lab.
It’s fine, you have plot armor.
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Or, you get sucked into the void and your soul is placed in the body of eight-year-old Sans.
Arc 1: Heritage (1-7)
Arc 2: Hell (8-10)
Arc 3: Home (11-45)
Arc 4: Heart (46-59)
Arc 5: Hostage (60-76)
Arc 6: Home [Reprise] (77-90)Series
- Part 1 of How To Be A Human Being
- Part 1 of Hounds Of Love
- Part 1 of I/Me/Myself
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Making A Monster by absurdmagewrites
Fandoms: Undertale (Video Game), Underfell-fandom, Underswap-Fandom, Swapfell-Fandom, Fellswap-Fandom, Fellswap Gold-Fandom, Horrortale-fandom, Crafttale-Fandom, Seaswap-Fandom
03 Mar 2026
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Sometimes life throws you a curveball. For you, your curveball was going to bed looking like a human, and waking up looking like a monster.
A skeleton monster to be precise.
With the barrier breaking, a large surge of magic descended on the town you live in, and transformed you overnight. Unsure what to do with you, and the others changed, you're ushered into a facility until a monster with similar magic can take you to teach you how to wield the now uncontrollable magic you've been given. After waiting in this place for four years, you'd given up hope that anyone would ever want to take you.
What a surprise for you when you find out that someone does. A lot of someones.
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You and your family are just enjoying a nice day at the park, when a life changing event happens that ruins everything.
You get taken away to a facility to be tested on...
Life doesn't feel as peaceful as it once did, you hated your new life.
"I wish I could just go into those story books I used to read..."
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Sans has wanted Grillby since he's met the man. Unfortunately Grillby is incredibly off limits because of the monster owning his soul.
...
Maybe Sans should've asked more questions.
Series
- Part 13 of I/Me/Myself
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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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Wake up buried in snow, alone, and with no memories?
Check.Keep seeing numbers, words, and random text floating around every object and surface as far as the eye can see?
Also check.Why does every person he meets say he needs help?!
He’s perfectly fine, if you ask him.“I wonder what determination tastes like.”
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Note from the author:
This is my take on Fatal Error — a much more non-canon,[this isn’t even OOC, this is just straight-up a different person with the same name]
amnesiac version of him.
He’s also not fully canon-compliant in terms of power scaling and may even have a different origin and and backstory.It’s my reimagining of him with a completly diffrent story.
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Monsters came out of the mountain last year. An unknown number societies filled with creatures small enough to be held with one or two hands. Without their Core, their Souls need to gain ‘magic’ from Human Souls caring for them. So of course, shops popped up all over the place advertising different ‘varieties’ of ‘Bitties’ for Humans to ‘adopt’.
I’ve seen plenty of these poor little creatures up close and I’m telling you, these are tiny people who deserve more than pet status. Not to mention the fighting rings. There’s intelligence in their eyes that I don’t even see in half the Human people I encounter. Not that I’m particularly interested in encountering people. My street cat Emily and I prefer staying at home, making just enough money off of my video game streaming to stay afloat.
Emily is an odd cat. She came into my life freshly pregnant and demanding to be my cat. Her cool as fuck skeletal pattern gave me the idea to keep my identity online a secret by slapping on skeletal face paint. The viewers love it.
Sadly, Emily gave birth just a few nights ago, to a litter of stillborns. She’s been beyond miserable. She goes out every night now, I’m really worried about her.
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Continuation of "Pretty Like A Car Crash"
Crumble must prove to the facility that she can handle whatever is thrown at her, except sometimes the problems come from the skeletons that are supposed to help her.
It's up to her to prove everyone wrong.
Series
- Part 2 of Crumble and her Crumbling Life
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Palette, the child of the Guardian Of Positivity and Protector Of AUs, is use to being alone. But eventually his little mind grows curious. Wanting to be like his parents and helpful, he runs away one day and begins his little journey of explornation! Until something comes along his way... Will he be able to advoid it and achieve his goal in the end?
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Sans has put in the bone work.
For fifteen years, he's raised Papyrus.
Not even counting the time loop.
And now some pretentious ancient bones want to have a say?
Oh hell no.
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Said "ancient bones" are mortified.
How were they supposed to know the short depressed skeleton was barely two decades old?!
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You find yourself out of a job, on the verge of getting kicked out of your apartment because you can't pay the rent and no where to go. Until your newest skeleton friend suggests you move in with them and their cousins until you get back on your feet again. You didn't expect to like living with this many people at once so much though...
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Undertale & Deltarune Drabbles by DeckofDragons
Fandoms: Undertale (Video Game), Deltarune (Video Game)
24 Jan 2026
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A series of unrelated Undertale drabbles and now some Deltarune drabbles too!
I take requests for these.
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Dream’s life shattered before Nightmare’s very eyes, his brother’s future being wiped out in one bite of an apple. A golden apple. He had been eating so many that Nightmare knew the positivity would overwhelm him and his senses, it’d become toxic. Corrupting.
This wasn’t right. This wasn’t right at all.
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After Dream eats all the Positive apples out of the Tree of Feelings, he corrupts into Shattered Dream. Slowly, due to this error in the code, the Multiverse begins to break - and Nightmare is at the centre of it all.
Series
- Part 1 of Longfics
- Part 1 of Apple of My Eye
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Souls are one of the most powerful forms of currency. Demons use them as a food source while Humans use theirs as a bargaining chip. Most Demons aren’t physically capable of taking human souls, so in order for them to feed, to truly feed, they need permission. This caused the creation of the soul deal where the Human gets something, anything in return for their soul.
Though people don’t realize that Demons have souls too. They aren’t the same as human souls but they have similar properties. Meaning a Demon can sell their souls to another. I’ve never heard of it actually happening as a Demon risks death as unlike humans they can’t survive without a soul.
Until in the dead of night a loud crack of magic surged through my tiny cottage. Alerting me to a situation in my kitchen. I found the tiles covered in thick layers of blood and white dust. Amongst the chaos was two skeletal Demons with one who was gravely injured. The other looks at me with fiery purple eyes.
Saving this Demon would change the very foundations of my life. As that single action tied me to them. All fourteen of them from every ring. Will more deals be made? Or will these Demons devour me whole?
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Underlust Mettaton has a "great" time in the multiverse. Or a better description: Papyrus gets kidnapped, and Mettaton goes hunting.
This is very much a self-indulgent/vent fic. I'm tired of Sans being the only character talked about; he's the strongest, the coolest, yadda yadda. So I decided to write a fic with the premise of, "The sans multiverse discovers they're not the only ones with power." And I went with Underlust Mettaton for that role because he's unassuming-looking, but should be way more powerful than generally depicted.
I don't actually hate the sans multiverse, I'm just not really into it. I've seen it be done hella well over the years. This story just isn't about that. -
sweetheart, give me something to work with by chorussfruit for minniegoodasgold
Fandoms: Undertale (Video Game)
29 Dec 2025
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Hearts asks Error for some help when he finds himself in a bit of a... bind.
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The Serif household has been through many odd scenarios. After all, they are entirely comprised of other versions of the same two skeletons who got stuck in the world they have called home for six years, unable to return to their worlds and thus forced to carve out a life for themselves until further notice. All things considered, they found their stride and adapted to the ongoing weirdness of universe hopping.
That is, until she arrived. Flora, a woman so out of left field and disrupting their normality, appeared in the basement, battered and bloodied to hell and back. Stuck like all the others who had appeared before her, the Serif household is forced to accommodate her until she stabilizes, slowly beginning to get to know the lackluster and stone-faced woman who ensures they don't injure themselves via stupid means.
Few expect her to open up. Fewer expect her to accept becoming friends.
None expect for any of them to become much, much more.
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Diary of a Tired Afro-Latina who Decided to Date 14 Fuckass Skeletons at the Same Damn Time by BiblicalBeasts, sagemelons
Fandoms: Undertale (Video Game), Deltarune (Video Game)
18 Dec 2025
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When you agreed to move in with your datemates, you didn't think shit would be so damn chaotic. They argue over the dumbest shit and somehow manage to drag you into it?? Honestly, if the sex wasn't so good, you would've run for the hills already.