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A Small Act Of Kindness(not really, it was actually quite important) by 3chovine
Fandoms: Undertale (Video Game)
27 Sep 2025
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Error breaks the Barrier.
Y'know, cause he's a good person now. And might as well use his human soul collection for something.Series
- Part 1 of DoodleVoid
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"Studying history sure is easy when you've lived through so much of it yourself!"
When the Barrier formed, it wasn't so easy for the Hammer of Justice.
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DELTATALE: UNDERRUNE by J88888888
Fandoms: Undertale (Video Game), Deltarune (Video Game)
01 Sep 2025
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the fun gang get dropped into random spots in undertale
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Songfic: Harpy Hare by Yaelokre
A story that ends when another begins. A child who changed history. A mother who wanted to keep them safe. A king who wanted best for his people. A story that would only be forgotten when the last listener is dead.
*Me trying to be poetic*Basically just headcanons and theories. Don't take this as a canon.
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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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The monsters had not been expecting the humans to attack. They were easily overwhelmed, forced back into the fallen city beneath the mountain.
A single skeleton child, separated from his family, finds himself lost in human lands instead.
And a single human child, trying to escape her own species, finds that the abandoned city she was living in is still, in fact, claimed territory.
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- Part 1 of My Undertale Backlog
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(Shoutout to T. Mark, R. March, and C. Enthus, the original TLRYheads.)
The sun rises as it always does over the eastern sea. In the impoverished fishing village of Callocast, twins Kas and Isri watch the sky light up together, unaware that their lives are about to change. Twelve years ago, the powerful and beloved Red Mage was murdered by monsters. Since then, the Magescourt has searched for the next child with such powers. Today, a company of mages rides into Callocast. Today, Isri's red eyes guide the twins' fate down a different path.
Thrown into a world of status and luxury at the Magescourt, mage of kindness Kas is overjoyed to see their sibling finally step out of the shadows. But things among the mages are not what they seem. Tensions between monsters and humans are rising, and the shadow of war looms on the horizon. Can the twins change fate, or is monsterkind's story already set in stone?
(Fan-prequel to Undertale, mainly focusing on original characters.)
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- Part 1 of FUSEVERSE
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Temporal Fenestra by aenor_llelo, Alderous, ConcoctionsFromHell, CryptkeeperKain, izziel_galaxy, Jaybird314, translunaryAnimus
Fandoms: Undertale (Video Game)
16 Nov 2024
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Temporal
1. relating to worldly as opposed to spiritual affairs; secular.
2. relating to time.
3. of or situated in the temples of the head.Fenestra
1. a small natural hole or opening, especially in a bone.
2. an artificial opening.Temporal Fenestra
1. openings in the temporal region of the skull of some amniotes, behind the orbit (eye socket).
2. artificial time windows.By complete accident, Sans discovers he's in a time loop. Entirely on purpose, he tells some guy named Papyrus. Despite himself, Papyrus wakes up every morning to meet a stranger named Sans for the first time.
Series
- Part 1 of Echtratale
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"Fuck, Sans... If you had killed this human the day you found her, we wouldn't be here..." Undyne whispered to him, filled with remorse and guilt.
She passed his hands behind his back, anti-magic handcuffs surrounding them. Checking their placing, she locked them.
Sans could not tell if she was hating him. Perhaps she was blaming herself, too. Perhaps everyone was feeling a little responsible. At least, he hoped so."Why did you do that?" she sighed, rhetorically.
"I did it out of love." Sans simply replied.
"That’s the stupidest excuse you could have chosen..."
•| ⊱❦⊰ |•
Corrupted by the Lust, monsters live a hell everyday, sex and immorality being a daily routine.
Sans is one of the most luxurious of them and then, the one who had always been the most disgusted by all of that. He lost hope. He lost will.One day, while going to this giant purple door, he found a package. A human baby. And strangely, Sans felt... at peace.
Now, Sans has something to protect from this world. And he is not going to give up, even when everyone seems to be against him. But it might be easier than he thought: it seems that this little girl can change hearts...
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Frisk finally defeated Omega Flowey and got out of the underground but as it turns out, contrary to their expectations. The Barrier wasn't broken and now they were in a random unknown location.
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While working on the machine, Sans receives a text message from an unsaved number.
It first starts out on one slow night that quickly evolves into eagerly waiting for a message from this unknown person.
Sans is cautious but he can’t help but feel drawn to this person - Despite that he never had met them before.
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WiseTale is one of the many prequels to Undertale, it is branched to the main timeline however whether it's the original history of Undertale is still unknown to this day. The AU revolves around the 7th forgotten human that fell after Chara, he is looking for his siblings as they fell down to the Underground. The seventh human is faced with a challenging path will he get to the barrier or will he fall just like...
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- Part 1 of Giroverse: The WiseTale Series
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Stuck in the facility Arius is miserable but she should be used to it by now, shes been stuck there for years.
in the case of Arius, monsters with her illness can grow tumors sprouting flowers from their bodies as a result of the ambient magic when expressing strong emotions.
In severe cases Victim's lungs or magical equivalents get filled with the flowers, leafy stems, painful thorns and, roots which grow in their respiratory system and burrow around and into the skeleton of the victim.
Eventually patients choke on their own blood or dust and petals,
Treatment: Varies based on severity
Diagnosis: Hybrid emotive variant of Hanasaki disease - severe
Monster Type: Skeleton
Gender: FemaleSeries
- Part 2 of The many that loved nothing
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Human magic before the Barrier was achieved through the Cooperative Connection, a bond wherein a monster gifts his or her memories, and thus a part of their soul, to a human. Discovered when Queen Toriel gifted a blind prince a blanket which she weaved in her memories of describing the starry sky far above her castle in the Monster Capital, the Cooperative Connection shines this trust both on the sleeves of human mages as well as in the relation between human and monster society. The trust of the Cooperative Connection exemplifies itself in the Monster Mages, humans whose magic makes them monsters in soul, tasked to protect monsterkind as the most powerful mages there are.
Follow Cter, as the war between humans and monsters come to an end, with nothing else than a total defeat for the monsters. The lives of those the Monster Mages swore to protect are now more in danger than ever.
For they will lose the very home they so wanted to protect.
Series
- Part 10 of Soul of our Hearts
- Part 15 of One falls anthology
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Human magic before the Barrier was achieved through the Cooperative Connection, a bond wherein a monster gifts his or her memories, and thus a part of their soul, to a human. Discovered when Queen Toriel gifted a blind prince a blanket which she weaved in her memories of describing the starry sky far above her castle in the Monster Capital, the Cooperative Connection shines this trust both on the sleeves of human mages as well as in the relation between human and monster society. The trust of the Cooperative Connection exemplifies itself in the Monster Mages, humans whose magic makes them monsters in soul, tasked to protect monsterkind as the most powerful mages there are.
Follow Cter, as the consequences of the Second Fusion thunder across a land already scared by the First Fusion. The return of the terror that cracked the relationship between humans and monsters.
Now shattered upon the battlefield.
Series
- Part 9 of Soul of our Hearts
- Part 14 of One falls anthology
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Human magic before the Barrier was achieved through the Cooperative Connection, a bond wherein a monster gifts his or her memories, and thus a part of their soul, to a human. Discovered when Queen Toriel gifted a blind prince a blanket which she weaved in her memories of describing the starry sky far above her castle in the Monster Capital, the Cooperative Connection shines this trust both on the sleeves of human mages as well as in the relation between human and monster society. The trust of the Cooperative Connection exemplifies itself in the Monster Mages, humans whose magic makes them monsters in soul, tasked to protect monsterkind as the most powerful mages there are.
Follow Cter, as the consequences of the fusion between a human and a monster soul settles in with the world around the monsters, with the humans so much more powerful than them.
Humans now know what the monsters never did.
Series
- Part 8 of Soul of our Hearts
- Part 13 of One falls anthology
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Human magic before the Barrier was achieved through the Cooperative Connection, a bond wherein a monster gifts his or her memories, and thus a part of their soul, to a human. Discovered when Queen Toriel gifted a blind prince a blanket which she weaved in her memories of describing the starry sky far above her castle in the Monster Capital, the Cooperative Connection shines this trust both on the sleeves of human mages as well as in the relation between human and monster society. The trust of the Cooperative Connection exemplifies itself in the Monster Mages, humans whose magic makes them monsters in soul, tasked to protect monsterkind as the most powerful mages there are.
Follow Cter, as a promise becomes an itch she can not scratch.
Series
- Part 4 of Soul of our Hearts
- Part 9 of One falls anthology
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Human magic before the Barrier was achieved through the Cooperative Connection, a bond wherein a monster gifts his or her memories, and thus a part of their soul, to a human. Discovered when Queen Toriel gifted a blind prince a blanket which she weaved in her memories of describing the starry sky far above her castle in the Monster Capital, the Cooperative Connection shines this trust both on the sleeves of human mages as well as in the relation between human and monster society. The trust of the Cooperative Connection exemplifies itself in the Monster Mages, humans whose magic makes them monsters in soul, tasked to protect monsterkind as the most powerful mages there are.
Follow Cter, as the consequences of the fusion between a human and a monster soul comes to change the world beyond what it did the human and the monster which died to form it.
A fusion to split an entire world.
Series
- Part 7 of Soul of our Hearts
- Part 12 of One falls anthology
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The first time Doctor W.D. Gaster takes S-01 to see the BARRIER.
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Human magic before the Barrier was achieved through the Cooperative Connection, a bond wherein a monster gifts his or her memories, and thus a part of their soul, to a human. Discovered when Queen Toriel gifted a blind prince a blanket which she weaved in her memories of describing the starry sky far above her castle in the Monster Capital, the Cooperative Connection shines this trust both on the sleeves of human mages as well as in the relation between human and monster society. The trust of the Cooperative Connection exemplifies itself in the Monster Mages, humans whose magic makes them monsters in soul, tasked to protect monsterkind as the most powerful mages there are.
Follow Cter, as she comes to understand what it means to have discovered something that should never have come to light. The truth of the Cooperative Connection, laid naked for the world to see.
And the consequences of its reversal.
Series
- Part 11 of One falls anthology
- Part 6 of Soul of our Hearts