Fellswap Prodigal

Coming soon.

## Story Prose

TW: This story contains depictions of violence, blood, death, genocide, religious terminology and experimentation. It depicts scenes involving spiders, cruelty towards children, killing of animals, and major character death.
Fellswap Prodigal – 1
Mother River gave the order. The monster WingDings Gaster was captured and brought to the Holy Sanatorium. The priestess had spend days before, studying the notes and powers bestowed to them by the devil named Error, and felt prepared to begin the experiment.
The faces of their sisters and brothers, Undyne, Muffet, Grillby, Napstabot, twisted in sympathy as the poor monster screamed. They couldn't understand his words through that cryptic font, but River knew he must have wondered what he did to deserve this...
But the will of Mother River would not be defied. The only one of greater authority was the Queen herself.
They needed to create Papyrus and Sans, as seemed to exist in every AU but their own. But, it would be a shame to waste a soul. Gaster's survival was unnecessary, and so, four more skeleton children were created.
Deep into the night, after the other staff had turned in, Mother River remained in the lab. They took physical notes while continuing to look at a hologram tablet, endlessly fascinated by the existence of other worlds.
“Why did you make six children? Only Sans and Papyrus matter,” came Error's voice from the shadows.
“Glad to see you in good health, my devil,” River's hood turned to him. “Why not? Besides, if I'd let Gaster live, he might have been a nuisance.”
Arms folded, Error approached the six tanks where the first signs of tiny bones began to grow. “Be careful. Though you desire survival, you might defy the code too far. I can't predict what it would do.”
“In truth, I want to see if I can make the children viable for holding Determination. And if the reports are correct, it's best I begin with prototypes before implementing such on the classic pair.”
Error chuckled, “You're smarter than I gave you credit for.”
“I've done my homework. And I can see why you value this 'Classic' timeline so dearly. It truly is the original, the sire of all these worlds...”
“Ugh, finally someone gets it!” Error held out his hands. “Can you see now why nothing else matters? It's the only one that should exist!”
Mother River fell quiet, making it clear they didn't agree. The whole point was to prevent this world from falling into oblivion.
“Doesn't that unsettle you? That none of you are originals? That you lack true individuality?” said Error, approaching them.
Fellswap Prodigal – 1
Mother River gave the order. The monster WingDings Gaster was captured and brought to the Holy Sanatorium. The priestess had spend days before, studying the notes and powers bestowed to them by the devil named Error, and felt prepared to begin the experiment.

The faces of their sisters and brothers, Undyne, Muffet, Grillby, Napstabot, twisted in sympathy as the poor monster screamed. They couldn't understand his words through that cryptic font, but River knew he must have wondered what he did to deserve this...

But the will of Mother River would not be defied. The only one of greater authority was the Queen herself.

They needed to create Papyrus and Sans, as seemed to exist in every AU but their own. But, it would be a shame to waste a soul. Gaster's survival was unnecessary, and so, four more skeleton children were created.

Deep into the night, after the other staff had turned in, Mother River remained in the lab. They took physical notes while continuing to look at a hologram tablet, endlessly fascinated by the existence of other worlds.

“Why did you make six children? Only Sans and Papyrus matter,” came Error's voice from the shadows.

“Glad to see you in good health, my devil,” River's hood turned to him. “Why not? Besides, if I'd let Gaster live, he might have been a nuisance.”

Arms folded, Error approached the six tanks where the first signs of tiny bones began to grow. “Be careful. Though you desire survival, you might defy the code too far. I can't predict what it would do.”

“In truth, I want to see if I can make the children viable for holding Determination. And if the reports are correct, it's best I begin with prototypes before implementing such on the classic pair.”

Error chuckled, “You're smarter than I gave you credit for.”

“I've done my homework. And I can see why you value this 'Classic' timeline so dearly. It truly is the original, the sire of all these worlds...”

“Ugh, finally someone gets it!” Error held out his hands. “Can you see now why nothing else matters? It's the only one that should exist!”

Mother River fell quiet, making it clear they didn't agree. The whole point was to prevent this world from falling into oblivion.

“Doesn't that unsettle you? That none of you are originals? That you lack true individuality?” said Error, approaching them.

Fellswap Prodigal – 2

“Is the sparrow unsettled that it's feathers aren't unique? Or how much it behaves like the generations of sparrows before it? Or does it worry more about where it will find seeds and worms and the avoidance of predators?”

“Is that supposed to be humility?”

“Of course. All that matters is survival. The relevance of this 'classic' timeline means nothing to me.”

Error growled, but Mother River held up a gloved finger. “But- That does not mean I find no use in it. Why is it all these worlds seem to be copies, or at least, carry similar patterns from the original? Why shouldn't the multiverse be filled with worlds that bare no resemblance at all?”

The devil gave a shrug. “Does it matter?”

“Perhaps the solution to your problem, the existence of all these anomalies... exists somewhere within the original. Something must have happened there... something that connects all these worlds together.”

“If your asking to go to the classic timeline, the answer is no.”

“I'm asking if you've ever been in the classic timeline yourself.”

“Pff, of course I have. I'm from a classic timeline-”

“And you truly can't remember how the multiverse came to be?”

Error pulled a string from his eye, shooting it to wrap around their neck, “DO NOT interrupt me!”

Mother River fell quiet, realizing she'd overstepped. After a moment, Error relaxed, letting the string fade away. “And no, I can't. Falling insane in the Anti-Void for several months did hell on my memories...”

“Hm...” River rubbed their invisible chin. “I have a feeling... the patterns that appear in the different AUs, these are of no consequence. No more than DNA being randomized in offspring. If you want to know why the AUs exist, the answer is somewhere within the original.”

The devil went quiet, seeming to seriously consider her suggestion.

“I suppose I could do some investigating in the classic timeline...”

Papyrus barely remembered his siblings. The most he remembered was their varying heights and their screams through the walls. His own screams joined theirs when the plate was drilled into his hand, 1-P MRP.

He was alone for a long time, locked in a small room and closely monitored by the clergy. But one day, he was brought to play with one of his siblings.

Fellswap Prodigal – 3

They were the smallest one he could remember and appeared even more fragile. Papyrus couldn't help but be curious, crawling up carefully to observe the other creature. He poked them a little, and they poked him back. Their handplate read 6-S MRP, the bone still red from irritation.

“Papyrus, this is Sans. Sans, this is Papyrus. You two are brothers. And the both of you will be together for a very long time...” explained the tall invisible monster in white robes.

He barely understood the meaning of those words then. All he did know is it was nice to not be alone anymore, to have someone to talk to. The clergy taught Papyrus to read and write and how to do math. Sans seemed to struggle a lot with these things, so Pap would do whatever he could to help his brother when they were left alone.

Neither of them knew what had happened to the other children. Their voices through the walls had grown quiet. Papyrus wondered if they'd disappeared completely. Fearing Sans would be taken away and disappear too, he had to make sure his brother didn't displease Mother River.

But no matter how they performed, the pain did not end. The experiments continued- with magic being pressured into their souls and small doses of Determination being carved into the calcium.

Papyrus hated the spiders. Controlled by Sister Muffet, he was told to be still as they crawled inside his skull and rib cage, embedding grains of DT.

It seemed all the worse for Sans. Many times his brother came to the edge of death. When ever they took him away, Papyrus begged Mother River to let him go- to take him instead.

“I will do whatever is necessary for our survival,” they said.

“our survival!? or yours!?” said Papyrus.

Even though he couldn't see their eyes, he felt that disapproving glare upon him. He knew then things were only going to get harder.

One day, his purpose would be made clear. Papyrus was made to fight and kill a variety of animals in Mother River's tests. A killer. “Someday, a human will come that can not be stopped, regardless of our weapons or defenses. And so, it is your purpose, Papyrus, to put a stop to them. To make them give up on the genocide of our people.”

“to make them give up? am i not supposed to kill them?”

“... you are to kill them. But this human can not be stopped by death.”

Fellswap Prodigal – 4

“HOW CAN SOMEONE REFUSE DEATH?” Sans asked along side Papyrus.

“It's a power called RESET. There are some humans who are born with the ability to create limitless Determination. It allows them to refuse death and re-attempt whatever scenario killed them,” she said, all while showing them images of what it looked like from a human's perspective.

“HOW CAN WE POSSIBLY FIGHT THAT? IF THEY CAN KEEP TRYING TO KILL US OVER AND OVER?”

Mother River held up a gloved finger. “Ah, my children. That is the purpose of your suffering. I must not fail where others have before me. I am attempting to give you the power to create Determination... to beat the human at their own game... It is not enough to absorb human souls and become a god. The records have shown even gods are felled by a human with the power of Reset. The both of you must also defy death.”

Understanding why made the pain a little easier. Papyrus and his brother had to find a way to become unkillable- to exhaust this prophesied human into submission. Only then could their world, and their people, be saved.

One night, Papyrus woke from a strange dream he couldn't remember. There was a light in the darkness. A white light that read CALIBRATE. It looked like the RESET power he had once seen- and so he reached out to touch it.

Sans woke from his sleep, screaming. That same bright light shone from every hole in his skull and from his soul. Panicking, Papyrus screamed too- screamed for help until one of the clergy came.

His brother was taken away, leaving Papyrus alone and in fear- that strange button might have killed Sans.

In the morning, Mother River came for him. He was brought to see Sans, who had been rattled by the experience, but remained in good health.

Mother River's voice was laced with glee. “It seems we have made a breakthrough. Sans has been granted the power of foresight.”

“Sans can see the future? but i saw something- a button called CALIBRATE, when i touched it, that's when the light came out of him.”

“CALIBRATE?” said Mother River, before leaning down close. “Show me.”

Papyrus regretted that day. He shouldn't have told Mother River what happened. Because from then his CALIBRATE button would only bring his brother more suffering.

Fellswap Prodigal – 5

Though the physical experiments on Sans became few and far between, every day Papyrus would be expected to press the CALIBRATE button, in which a clergy member after would record Sans's predictions.

They were always extremely accurate, preventing many losses around the underground from accidents or conflict. At first, it was Mother River who received credit for these prophecies. But now that they felt Papyrus and Sans had become something of use, Mother River presented the two brothers before Queen Toriel.

Nervous, Sans and Papyrus had heard about the Queen from Mother River's staff. That she was stern and ruled monsterkind with little tolerance for disloyalty. But when they saw her for the first time- she seemed to be a kindly old woman.

Though the terrible clawed scar across her face made her seem a little scary, she gasped in awe upon seeing the two of them and asked for their hands. “Tell me your names, children.... So, it is you we have to thank.”

Mother River watched the interaction quietly- always hard to read, given they had no face. “Mother River, these boys will be staying with me from now on. For ones so young, they have given so much for monsterkind. They shall be my sons and my heirs.”

The invisible monster gave a bow. “As you command.”

“heir? what does heir mean?” Papyrus asked his new mother as they were shown their rooms. A tower overlooking the city, fit for royalty.

“It means that you are now princes. And one day, you will be king,” Toriel said, still holding both of their hands.

“PRINCES!? WE'RE PRINCES! HOLY SMOKES! PAPYRUS, IT'S JUST LIKE A FAIRYTALE!” Sans said, all too thrilled by the idea.

Even with their new titles, Mother River stressed the importance of continuing her experiments. The boys were not completely liberated from their suffering. But- at the very least they had someone to complain to if Mother River pushed them too hard.

Life went on like this. Papyrus and Sans, two children surrounded by adults expecting much and uncertain if they could provide.

It came from Sans's visions that they knew for certain this genocidal human would come. And with each new variation, new defenses and weapons were built by Sister Undyne to prepare for that fateful day.

The Bridge Jumpers – Fellswap Prodigal – 6

Though they had no friends, at the very least Sans and Papyrus had each other. Around adults, they had to speak to the full scope of their vocabulary and respect. But in the long nights and those brief moments away from the clergy, they could be themselves, just children.

“HEY PAPYRUS, WHAT DO YOU THINK IT WILL BE LIKE WHEN YOU BECOME KING?” Sans asked, the lights out and the echo of their voices hidden by a soft rain.

“well, i'll get rid of mother river, that's for sure...” Papyrus groaned, his skull still aching from another DT session.

“BY GET RID OF... YOU DON'T MEAN...?”

“why not? it's not like they wouldn't deserve it.”

“BROTHER!”

“i'm just kidding bro,” he said, though he really wasn't.

“YOU BETTER... I THINK YOU SHOULD- AND YOU WILL BE A GOOD KING. YOU CAN BE NICE AND KIND... WHEN YOU REALLY WANT TO.”

“you'd probably be a better king than me. you're better with people...”

“BUT I WON'T EVER BE KING. ONLY CHANCE OF THAT IS...”

Papyrus rolled over to look at Sans. “that's not- i mean... i don't want to be king. i just think you'd do a better job.”

“BUT- YOU'RE A LOT SMARTER THAN ME, AND STRONGER TOO.”

“that's not true. and besides, you got something i don't. charisma.”

“UGH, YOU'VE SAID THAT BEFORE- I STILL DON'T UNDERSTAND WHAT THAT MEANS!” Sans patted his knees in frustration.

“it just means you're a natural- people like you for who you are. unlike me. the clergy hate my guts. remember that time i bit sister undyne?”

“I DON'T LIKE THINKING ABOUT THAT. I KNOW I LAUGHED BUT... THEN MOTHER RIVER DRILLED THOSE SPRINGS INTO YOUR JAW...”

“yeah but... it's funny now, i guess.”

“I DON'T LIKE IT WHEN YOU'RE HURT. ONE DAY, MAYBE WE CAN BE KINGS TOGETHER? I'D FEEL MUCH BETTER WITH YOUR HELP, PAPYRUS.”

Fellswap Prodigal – 7

Papyrus closed his eyes with a soft smile, “it's the best idea ever, Sans.”

Being king didn't matter to him. All that mattered was remaining together. Though he felt his CALIBRATE ability a curse, it had been a small blessing- only working so long as they remained a pair.

After their nineteenth birthday the human arrived. Of course, Mother River had calculated the day via Sans's visions- and the whole of the underground went into lockdown- prepared to defend and fight for their lives.

At first, things seemed well enough. Every screen in the kingdom was tuned to Undyne's various hidden cameras as the human exited the ruins.

Tens of thousands of deadly traps had been meticulously planned throughout the route to New Home. Sat next to Sans, Papyrus remembered that moment well- the first trap. The human walking straight into, cutting off their leg, leaving them to bleed to death. At first there was a moment of doubt. Was this truly the merciless killer Mother River had warned-

The first RESET. Papyrus woke in his bed- and everyone was planning the arrival of the human. Only he remembered the human had already arrived.

It was then the true terror of the RESET ability became clear.

Endless chances, endless possibles, to circumvent nearly two decades of careful planning. Every effort laid to waste.

It was maddening, to say the least. Papyrus being the only person to bare witness to the true horror. Each time he attempted to warn Mother River and the others what was happening- and they only began to believe him as they watched the human navigate their maze.

Even so, it wasn't enough. The human's progress crept forward as a growing inevitability. All those years of training, the strength Papyrus had build- and he would be trapped in the castle, mentally wasting away, waiting for his opponent's arrival.

Some days Papyrus didn't even bother getting out of bed. Sometimes he'd sneak away before the maids could come to wake him. In these days he was desperate to scrap any variety he could from the world around him.

It would take over 800 resets before the human arrived at New Home. In this time, the terror in the people build up. To them, they only witnessed the human navigating their defenses like an omniscient being.

When the human arrived at their gates, Mother River approached Papyrus, who did not seem to share the people's terror. “... you know something.”

The Bridge Jumpers – Fellswap Prodigal – 8

“can you guess that i've already told you this hundreds of times before?” he said, not looking up from the book he flipped through.

Mother River gave pause. “I suppose you have. And in all that time, you have learned nothing to stop the human from breaching our gate?”

Papyrus groaned and shook his head.

“I see... very well. Then this is goodbye. Hopefully it will not be our last, your highness,” said Mother River, before departing.

At first disinterested, he realized they had never said that before. Bolting from his seat, Papyrus made chase, asking where Mother River had gone-

Another Reset. But this one was different.

Mother River had completely vanished. Nor would she ever return.

What happened? Papyrus was sure they had been there every reset before- how had they escaped? And why hadn't they bothered to help him or anyone else get out either? For the first time Papyrus felt... abandoned. As much as he'd wished for River to disappear, now he just felt angry they finally had.

The human would eventually arrive in the Judgment Hall, covered in the dust of their felled armies. And Papyrus would be waiting to face them, as Sans had always predicted would happen.

And due to the visions, Sans came to the Judgment Hall as well, prepared to fight, standing behind his brother.

“Sans, you need to go hide with everyone else!” said Papyrus.

“I'M NOT GOING TO LEAVE YOU TO FACE THEM ALONE!” Sans persisted. No matter what Papyrus did or said- in no reset would Sans leave.

And because Sans was nearly as powerful- but physically weaker- the human would always kill them first.

Ten times. Twenty times. Fifty. Even though Papyrus held the human off, the despair of watching Sans die slowly graded over him. Eventually, he could take no more.

If Sans is going to die, it will be by my hand.

Turning from the human, he approached Sans before stabbing a sharpened bone through his chest. The look of betrayal burned into Papyrus's memory, which faded to an understanding smile. “IT'S ALRIGHT. I UNDERSTAND. I'M SORRY I COUDN'T BE STRONGER...” he said, before turning to dust in his arms.

Fellswap Prodigal – 9

But even Papyrus couldn't continue giving Sans a respectable death. The human kept trying to defeat him. And with each attempt Papyrus grew more numb. Eventually, he didn't even look at Sans. He'd summon a rain of bones to quickly render his sibling to dust.

At some point, Papyrus lost count of how long he and the human were locked in battle. Though each attempt reset his physical strength, his mind was degrading- along with his magic.

Finally, the human's knife pierced Papyrus's chest. The shock and pain sent adrenaline through his body. Stumbling back into a pillar, he clutched the wound before sliding to the floor.

The human, with those red eldritch eyes, giggled before moving past, leaving him to suffer.

Tears fell from his eyes. And yet, there was relief... maybe this suffering was finally over. Closing his eyes, he let the darkness take him.

And yet, he didn't die. Something like an earthquake woke him- the loud sound of crushing, the shaking of the earth. Cracks appeared all across the hall and the floor itself began to heave.

Gasping, Papyrus stumbled to his feet, finding his second wind. Mom. Queen Toriel- maybe she-

Even through the pain, Papyrus ran for the castle- giving a guilty glance at his brother's dust. But he wasn't sure how long he'd been unconscious- or if it would be possible to save his mother's life.

As he ran across the bridge connecting his home to the Judgment Hall, he could see the city all around him, collapsing- What on earth was happening? Surely this wasn't the human's doing?

But before he could reach the front gate, something caught him by the leg- throwing and twisting him in the air. Blue strings wrapped all around his body, digging into the bones and held tight.

Papyrus screamed and struggled, held in the blinding white as his home crumbled all around him. After several long agonizing minutes a figure descended from the sky. A skeleton with black and red bones.

Who the hell was this? As Papyrus stared into those red eyes- that expression. “S-Sans?” The true judge who knew all his sins.

“... forgive me...” he pleaded, though after all he'd done, he deserved none.