Unwanted consequence of an experiment went wrong, prince Asriel Dreemurr finds himself reborn as a soulless flower unable to feel love or compassion. When confronted to death, he discovers himself a new power : Determination. The resolve to change fate. With the ability to travel through time and erase the consequences of his actions, the prince now held the power to play god.

A story of a foolish girl who fell...and finds herself trying to stand back up. A story of a scientist who ends up trying to save her. The story revolves around Gaster and Frisk, but more character will be introduced as time go on.

(This is a remake of the original What if) Down into the dark, Chara fell. Down into the dark, an experiment was run. What if she got to go home? But what if it wasn't to the world as she knew it? What if she was placed into another, at another time? What if that happened to be a version of Underfell?

Sans goes to work at Hotland's laboratory, as usual. But today something different will happen to him, something very, very interesting... A (I hope) unique take on W.D Gaster's incident. One-shot.

Chara is angry. Why? Because Sans was kicking her ass and killed her 10 times already. With his attidute and his stat's defining moves. But she makes a fatal mistake that results in her losing the option to fight back, every monster being revived, Frisk no more being blinded by LOVE and her only choice is to RESET.

Frisk has Reset hundreds of times while searching for an ending that is just out of reach. When a run ends differently than any other, Frisk sees a chance to find the ending they truly desire and fulfill a promise they made long ago.

Seeking shelter from a storm, a blind child descends into a realm of monsters. A chance meeting grants him a companion in the form of a ghostly girl garbed in the colors of flowers. Yet, what seems but a simple adventure becomes much more as memories of dark pasts claw their way to the surface. Lives forsaken, a name unspoken... what does this new future hold in store?

Sans has questions: Who are these people? Why did they kidnap him, and how do they know so much about him? In any case, they don't seem too dangerous. What's the harm in sticking around to find out? After all, his life has always been pretty weird. Why would that stop now? Sans' memory has never been the best. History's forgotten far more. Oh well, at least they have each other.

What if you didn't destroy the reset button, but rather the menu? How does the world work when you cease to exist? What story will it piece together then? Hateful Glitch explores that question with a new set of characters and enemies alongside some well know past characters who are...A little different. Second Story.

Everyone knows the story, the story of how Frisk fell into the underground, made many friends, and eventually set the monsters free. But what if that wasn't the end of the story? What if there were someone who simply couldn't move on after the monsters were freed? Someone who's tired of being alone in the dark. Can Frisk avoid the consequences once again? Or is it already too late?

A human falls into the Underground, and quickly realises that everyone there is either drunk, stoned, or completely off their face. Will they succumb to the temptations of the Underground or stay sober? [Contains a lot of drug use, swearing and graphic depictions of violence] {cover image by u/ipoststupidthings on Reddit)

What if two humans were in the Underground at once? What if one human was DETERMINED to stop the other? What if they could both SAVE? What happens when an Unstoppable Force meets an Immovable Object? When a certain scientist pulls enough of himself together, he finally finds a way to stop the destruction of his world. (Undertale AU. Rewrite of DT.)

Hope is a young girl with an open heart and a friendly manner who only wants everything to work out. What happens when a young girl with a green soul finds a family in a skeleton and a goat mom? Will life remain in the ruins or will it continue into something more? Time will tell if only it could...

"Do you want to be the first human on Mars ?" Frisk had never planned on being an astronaut, but with only limited time to prepare for a 8 months trip on their own and no hope of coming back to Earth after that, their SAVE power made them the perfect candidate and their help was requested by the space agency itself. Being given such an opportunity... How could they have said no ?

The Underground is divided. Evil lurks in the darkness as hope slowly fades away. Only a human, a monster, and a dead prince can restore this corrupt kingdom, but not if it corrupts them first.

Como científico real, Gaster debe ver siempre por el funcionamiento de todo pero eso ha llegado a costarle mucho más de lo que imagina, y por eso mismo el rey debe encargarse de él, pero ¿hasta que punto? ¿Cruzarán la linea más allá de la amistad? [NSFW]

Eran las primeras vacaciones que se tomaba. Sans pensó que serian relativamente tranquilas, claro, si se ignoraba los gritos de su hermano, Papyrus, y el enamoramiento de este con Frisk; la molesta y deportista Undyne, intentando que se levantase del sofá y moviese el esqueleto; además de la familia Dreemurr, conocia a Toriel, pero sus hijos eran otra cosa. [Chara x Sans] [Chans]

Sometimes, those who FIGHT must cast aside their battleclaws. Follow the story of Undertale through the eyes of Ginger Wingren, a young Barn Owl who ends up trapped within a human's pelt beneath Mount Ebott. As she adapts to her featherless form and new environment, she learns about monster history, interacts with the locals, and most of all, uncovers the hidden strengths of MERCY.

...I don't know if this is a good thing or not. I don't know whether I should have just stayed home, or done more. I don't know if I should have gone up that mountain that day...or meet any of them. ...but do I regret it? Not for a second.

DIRECT SEQUEL TO "PATCHWORK SOUL" — A few months later. A family of monsters and their little human kid try to start life anew beyond the confines of a giant mountain. Maybe they find something. Maybe they lose something. Time flows ever onwards, but sometimes it goes sideways, and it's heavier than they thought.

The adopted daughter of the King and Queen of monsters, a young girl who can't handle humanity, both abandoned the civilizations of their birth species, lived a century apart, now they must work together to free the Underground and allow the monsters to see the sunlight once more. But will they be able to succeed, or will a certain flower stop them? Time will tell. Charisk.

Frisk and Chara, pacifist and genocide. two sides of the same coin, not always in control. What if someone new stumbled into the mix, dragging behind him his own troubles, something...otherworldly.

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.

There are monsters in the forest. Now trapped within the endless woods surrounded by mask-wearing individuals, it is up to Frisk to discover the truth of the forest and to find the lost past of her mask companion all while hiding what she is from those who would seek to wear the skin of her face as their own.

Two essences in one body, it was never meant to last. Two weeks after monsters' freedom, the unlikely cohabitation between Frisk and Chara within one body starts breaking down. Frisk's body pays the price while both of their consciousnesses slowly start blending together. As they become a kind of human amalgamate, the two begin losing themselves more and more with each passing day.