Actions

Work Header

Fate/Scarlet Order

Summary:

A long time ago, two races ruled over earth. Humans and Monsters... but that's a story everyone has heard before. The laws have been changed, fates had been broken, chains had been mixed, concepts and reality itself had been shattered against their will, and reborn into something that shouldn't be possible for the Underverse's standards.

"My Child. You've gotten an invitation."

"Hm?... Chaldea? What's this about?"

Frisk looked up at his mother with intrigue, his eyelids opening up slightly, the soul of determination sat on his chair, looking at the letter that had just arrived, before the former Queen of Monsterkind took her phone, contacting her ex-husband and the rest of her friends for some advice. For some reason... not just her, but Frisk as well had a bad feeling.

A very... very bad feeling.

Notes:

Ok so... I decided to take a gamble. I promised myself a long time ago I would NEVER make a fanfic. EVER. "Why?" would you ask. You see, I'm the kind of person who moves on from one project to another as soon as possible: I don't like having "unfinished" business, so to speak, which is why I could never make a fanfic, and all my stories are just one-shots.

However... I decided to take a gamble. For around three days I've been thinking of how it would work; to mix up the worlds and concepts of Undertale with Fate/Grand Order and throw in Frisk in it. How would it work? what would it happen? But despite my intrigue, let make myself clear: this isn't going to be a FULL story.

I don't have the strength, the potential, the will, nor the energy to dedicate YEARS of my life to telling the story of Frisk going through the Singularities and the Lostbelts, I just... don't have it in me. This is more of a story I wrote on a "whim", where I will only go on talking about Frisk's arrival to Chaldea, and him, Mashu, Olga and Cú Chulainn going into Fuyuki, Singularity F, and then I'll resume my current projects.

I hope I can inspire someone out there who is way more ambitious than me, who is way more young, and has a better will to maybe produce something greater and better than what I'll do. That's what you guys have to do: Stay Determined, and surpass those who came before you. Someone out there must surpass me, whoever it is, I pray you really do your best once you pick up the mantle.

See you guys on Chapter 1. I love you fellas. ~Miguel16310, February 21th, Friday, 2025.

Chapter 1: A new experiment

Chapter Text

Munch... munch... munch...~

 

The little grey-skinned girl rested her head against her open palm, her mouth filled with a cinnamon-butterscotch flavored candies she had manifested out of nowhere some minutes ago. Her empty eye sockets, emanated a soft green light, mixed up with both Zeros and ones, binary code; there was nothing. Nothing surrounding her except from the pitch black darkness, as her short, white hair waved slightly.

 

"Hehe..."

 

Her gaze was fixated on a sort of green-colored screen standing in front of her, numerous worlds and their timelines, alongside the AU's they belonged to were listed, one by one. A sigh escaped from her lips, one of relief and satisfaction, before one by one more and more screens started to pop around surrounding her, she didn't need to look around to ensure everything was working accordingly.

 

She felt it, and it was a true relief.

 

Despite everything working accordingly, her playful, malicious and slightly evil yet always joking nature, made her act. She wanted to explore and evaluate the integrity of the AU's herself. The girl let out a sigh as she spun around again, this time floating accordingly; before extending her open palm in front of her, out of the same, as if she was some sort of Deity, a slight bit of Ceroes and Ones started to emerge.

 

Like cockroaches, like hungry pests, they extended themselves, surrounding her, and devouring her shortly after.

 

"First, lets visit Underswap..."

 

.


.

 

BOOOOOOOM

 

Right after the laser collided with the ground, it caused an explosion. Papyrus, who had an annoyed expression, pointed his extended hand towards the place where he had just shot his attack, part of his skeletal shape already coated in sweat, the Judgment Hall being partly destroyed due to all the fight they had been going through so far. Two hours.

 

They had been fighting for two hours, and he was getting tired already.

 

"Freaking kid..."

 

Sans' older brother grumbled, his sleeve going to his face in a poor attempt to wipe off the sweat coating his face. Right as the cloud of dust started to vanish, the bloody figure of an eleven years old boy made itself known, wearing a blue sweater with only one pink strip on it. Part of the fabric was slightly torn, revealing underneath a blood-soaked black shirt, that stuck to his bruised and wounded body, yet he was still alive. The First Fallen of Mount Ebott, the adoptive child of Queen Toriel and King Asgore, and Prince's Asriel's so called "Older Brother"...

 

Frisk Dreemurr, who slowly stood up; the determined genocidal's face was coated in shadows; he wasn't panting. Despite all the blood he had lost, he kept advancing, he kept fighting, like a damn robot unable to feel pain. Papyrus, on the other hand, took a long drag to the cigar between his teeth, in a poor attempt to try and relax himself.

 

He had broken his right arm, and disintegrated the flesh on his left leg, but not even that was enough to stop him... not yet at least.

 

What the monster wasn't expecting... was for the human to pick up that scythe of his, despite his small frame and the massive size of that weapon, Frisk moved as fast as lightning, and hit with the strength of a damn truck, moving and waving it as if it was a part of it, and as if it was as light as a feather. Dreemurr pointed his own weapon to his shoulder, his sight still concentrated on the Judge, and then he did it. Papyrus opened up his eye sockets in shock as he felt a shiver running down each and every single one of his bones, as he saw, horrified, how the boy decided to cut down his own broken arm, when he realized he had no more leftover healing items.

 

SLASH~

 

The blood started to pour from the recently open wound, like a fountain, spraying itself across the beautiful hall and staining red the golden-colored ceramic. Determination's purple eyes focused themselves on his opponent, red light coming out of them, his emotionless face, his cold-hearted expression, told Papyrus all he needed to know. He only saw him as another obstacle in his way, the last one. His head went from side to side, what kind of monster did that Chara brat woke up? if things had been any different, he would've rather killed the girl and completely discard the promise he made to that old King back at the Ruins, a long time ago.

 

But this wasn't the time to mourn about what could've been, and never would be. The world needed him right now.

 

His hands extended to the sides; bones started to come out of the floor, destroying everything, with the intention to impale him. Frisk squeezed his scythe, the heart-shaped necklace in his neck shinning with a golden light, boosting up his defense, as the blade of his weapon overcharged itself with his own power, he waved it, squeezing the handle as hard as he could, an energy crecent moon emerged from its tip, the battle was observed quietly by the grey-skinned girl, who had a smile on her lips.

 

Everything was working just fine.

 

"Hmmm... Both genocide timelines, pacifist timelines and Neutral timelines lack any sort of anomaly as well..."

 

She muttered, focusing on her small screen, now completely ignoring the fight going on right in front of her. Her body was covered by the shadows of one of the multiple pillars, even if her hiding spot was destroyed, they wouldn't be able to see her. For them, she didn't exist, because that's what she wanted. She nodded slightly, before clapping, once again, her signature numbers came out of nowhere.

 

Zeros and Ones, swallowing her.

 

"How about Underfell... ?"

 

.


.

 

"Dear friends... Humans and Monsters here tonight!"

 

A beautiful girl wearing a red suit spoke, standing on a podium, her arms extended themselves outwards. The little stalker manifested herself piece by piece on a nearby building. Her right eyebrow rose up with curiosity as she saw Ebott's town in this universe, the window she had next to her was showing her she arrived to a "True pacifist" timeline, apparently, Frisk in this world had been born a woman, and had accepted to be the Ambassador of Monsterkind as well after breaking the barrier and showing them the true meaning of Love, and kindness.

 

Tonight was the seventh anniversary since the Barrier broke, so now she was a nineteen years old woman, soon to reach her twenties.

 

The woman opened up her eyelids slightly, the excited, joy-filled screams from both monsters and their new neighbors came out almost instantly at the sight of her beautiful eyes. Some children rose their arms to the sky, others blew their party blowers, as one would expect, the little orchestra  acted as well. Tonight as a night exclusive for celebration, the eight fallen with red-colored soul had a beautiful crown made of golden flowers on her head, alongside a small blush on her cheeks, despite all these years, Frisk still couldn't get accustomed to being the center of attention.

 

But she was willing to do her best for those she loved.

 

"First and foremost, please let me wish you all a very good night and give you a warm welcome, I hope you're enjoying the party... in second place, I wanna remark how grateful I am, my soul beats with happiness and it burns with bliss seeing how after all this time, with each passing day, our relationship improves..."

 

One would think she was exaggerating or reading a speech she practiced previously, but it would be a lie. Frisk never, ever had used already written speeches. She always spoke with full sincerity, using her heart first, and maybe that's what managed to bring peace to both races. The white-haired girl sighed, her hand now resting between both her hands, her elbows resting against her thighs, her gaze scanning the entire street.

 

It was packed, some humans went as far as to open up the windows to look outside their deparments, work offices or homes. They all shut their mouths as Frisk started speaking, behind here were Flowey, Asgore, Toriel, Papyrus, Sans, Undyne, Mettaton and Alphys representing Monsterkind as a whole, since they were the closest to the brunette, each of them muttering or speaking as lowly as they could so they didn't interrupt the girl who had given them a taste of Freedom. Despite still having some resemblance to their terrifying appearances from back then...

 

They all seemed way happier and more friendly than when she was a child. Damn it, they all changed their horrible philosophy of "Kill or be killed", Toriel and Asgore went as far as to go back together, as impressive and impossible as it sounded. Her small arms crossed themselves as she observed the ambassador walking, speaking about all that had happened these last few years, and the progress they had gone through ever since both species started working together as one. She nodded to herself, having seen more than enough.

 

"Underfell's timelines are also going decently well... "

 

The Screens, all at the same time, were showing other timelines happening at that same instant, other worlds, not so fortunate and happy as that one. In one, a genocidal version of that same girl fought against Alpha Flowey, who was doing his very best to make her abandon that dark path she was walking. In another Pacifist timeline, Asgore's trident and cleaver clashed against the Flower's roots, who was trying, in vain, to convince the small brown-haired boy to attack and fight back, they had gone way too far and performed multiple miracles by this point.

 

They hadn't kill anyone up to that point, so maybe... maybe just this one time doing so would be good? but Frisk insisted in his negative, as terrified as he was, violence was never the answer, it hadn't been ever since they started their journey, it wouldn't be so now at the end. The screen alongside the scene vanished; the girl stood up, clapping her hands slightly; reality around her broke at that very instant.

 

She had returned to her homeworld.

 

"StarTale, Outertale, Storyshift..."

 

The names came one by one, with her voice, without performing any action, the Alternative Universes started to pop up in different screens, alongside their nomenclatures that mixed up multiple numbers and letters, in order to differentiate their timelines from one another. Her eyesockest shone in green with more strength than before, she was absorbing information at overwhelming speed, it made no sense, but she had no issue in the slightest.

 

The she rose her left hand's index finger; triggering a list, led by a beautiful pink-eyed girl with brown hair and pink highlights.

 

"Alongside the security systems; they're implemented and waiting to activate the anti-viruses in case ay sort of anomaly in the timelines occurs... perfect. Everything is... "

 

She kept going, extending her right hand's fingers as if trying to hold something; the code condensed and piled up in a small vortex, eventually, casting a small table, alongside a chair, and a White tea set. From the small cup, some warm vapor emerged due to how hot the tea was. She took it to her mouth sooner rather than later, not before adding in some sugar.

 

"Perfect..."

 

Thus she completed her phrase, before enjoying how the exquisite liquid fell from her throat, having manifested some of the chamomile tea Underswap's Muffet liked to prepare for her clients, although next time she would add even more sugar, things like diabetes or illnesses didn't worry someone like her. Changing her posture into a more relaxed one, her work and daily check up having been done already.

 

While everyone did remember the X-Event, she couldn't care less. Their memories, traumas, whatever, she didn't gave a damn. As long as the Alternative Universes remained stabilized, and new timelines continued being born, things would go smoothly for the rest of eternity, as they had gone over the last one-hundred thousand years, and how they would keep going for the next billion years as well.

 

She sighed, before throwing the tea cup away, disintegrating it. What could she do to entertain herself? hmm... now that she had seen with her own eyes that everything was fine, perhaps checking up on Revenger, Error, Ink, Core, Fresh and the Omega Timeline wouldn't be so bad after all, she would never get bored as long as the Multiverse was ok, so many stories, so many worlds, so many timelines; so much to see...

 

So much to do... and so little time...

 

Just joking. Time... heh. She had always thought of that word to be slightly funny, just as the mortal's emotions. Despite her still remembering how she had been a very long time ago, she wasn't the same person. She wasn't a human anymore, she hadn't been one in a very, very long time, but it was ok. She wouldn't change her current state and life for nothing in the whole world, she wasn't that person anymore. After all... she was eternal. Eternal, invincible, unmovable, and as such, to observe and entertain herself with the lives of others was her right, her whim, her wish, and what made her happy.

 

It made her feel... alive...

 

"..."

 

Her eyelids opened up slightly. Something wasn't right... or more like; she wasn't alone anymore. Her posture however, didn't change not one bit, no. No, its not that she was scared or afraid anymore, what she felt was... genuine curiosity. The little both omniscient and omnipotent girl turn around, just as she had suspected, one of the only two people who had the right to get in her world, had accepted her small invitation.

 

As always, his broken skull greeted her, always smiling, empty eye sockets staring back at her. Hunched over as one would imagine, he waved his head slightly as a small greeting, a small bow that she replied back, although, just by waving her hand that is.

 

"Doctor W.D Gaster... Timeline 0.55-D, classic universe."

 

She revealed with no hesitation, the former Royal scientist rose slightly, or at the very least, he tried. Of course... he couldn't hide anything from her. Not him, nor any of his infinite counterparts. So similar, yet so different at the same time. Her small legs started to take her, walking around her current visit with a vibe of superiority, but with no hostility at all. Gaster wasn't following her with his gaze in the slightest, he just stood there, in complete and utter silence.

 

This was... intriguing.

 

What was he doing here? from what she remembered, his timeline had been erased by his Chara after the Genocide Route, Frisk didn't accept the deal of giving her his soul, thus, condemning it all to remain in perpetual darkness, with nothing but the Eight Fallen, the princess of monsterkind and of course... the Father of the Skeleton brothers, here present.

 

"..."

 

"Oh?~ what did you say?"

 

Was he... being serious?, even with all her power, the only thing she didn't do was spy inside the people's thoughts. Because that way they remained unpredictable, she only took that choice on "desperate" situations, situations that, oh look at that! never happened. Just as a green aura was coming out of her, from the creator of the Core, a purple aura emerged, both being quite intense.

 

His eye sockets had two small purple dots; his magic.

 

Her expression changed into one of intrigue; her small body rose into the heavens, binary code erupting from her hands, the numbers extending themselves from her skin, deploying another big screen, above all there was the same nomenclature. 0.55-D, the timeline where that poor bastard came from, she could've seen all its history, all the timelines that Frisk did until he had more than enough, and decided to go genocide...

 

But what interested her was something entirely different.

 

"Ah... so it was true... there's something quite strange in here..."

 

She noted, not giving a damn about the fact that his head was right behind her shoulder, as an inhabitant of the Void, he wasn't shackled to something as worthless and irrelevant as gravity, or the laws of nature. Both of them looked at each other briefly, she had just been looking for something to do, something to watch... and she had found it. Soon enough, she started to realize what he wanted, what he was looking for, and the motive of his unexpected yet welcome visit.

 

"..."

 

"Really?~ not even you?... well, understandable. You don't have enough power to force neither Frisk nor Chara to restore your timeline... much less change the past, present or future themselves"

 

Turning her back on him, she rose her shoulders and her hands, trying to show a lack of interest. Yet Gaster didn't say a thing, he just observed her. The power emanating from her, the numbers, all creation rested on the palm of her hand. That's why he took the chance of abandoning his mother land, and look for that brat's help. But the Risk had been worth it, no matter what happened... because he had no other choice.

 

Yes, he told the truth. He had no other choice but to look for her... and even if, truly, Frisk gave his soul to Chara and she resetted the timeline, there was no guarantee what he had seen... what he felt, became a reality. No. What he required was a trigger, something that rebuilt not just the entire world, but the universe itself, from its very foundation.

 

Something that altered the logic of the timeline, far beyond the "Preestablished laws" from all Alternative Universese and Timelines in the Underverse.

 

"HAHAHAHAHAHAH!!"

 

It was inevitable for her to start cackling. The bliss she felt, the excitement, oh heavens! Gaster saw his potential partner with attentive eyes, the black sweater she had, her grey shorts, her white hair, it all waved as if a storm was happening around them. Oh, oh, oh~ She hadn't felt this happy in a very long time! when? when? when was the last time she felt so much... adrenaline?

 

This... tickling...

 

How could she not be happy? once again, everything had gone well for her. Her body, overflowing with power, reality distorted itself, it broke in two as she let herself go, and then turned around, facing him one last time. Face to face, the dirty cheater, the traitor, the error yet ruler at the same time of all the Multiverse... and then there was him, him, the Royal scientist, father of the Skeleton Brothers, the man who speaks in hands, the Void's prisoner, the one forgotten by everyone, irrelevant, absent yet not fully.

 

"I accept your proposal, Doctor..."

 

She replied, snapping her fingers. With it, more screens started to appear. Gaster observed, attentively, how all past events of his home timeline started to vanish, one by one, they had never occurred. In the void, both Frisk and Chara; the humans, Alpha and Omega, vanished as well, as if they had never existed. His eye sockets closed themselves slightly, he wasn't resigned nor sad.

 

No.

 

He felt happy.

 

For the first ever in a very, very long time, Gaster was truly happy. He extended his right hand to her, in return she offered him her left hand, as a sign of acceptance for their new alliance. Both, the girl and the scientist, had a handshake, a tight one, as the entire world started to change, not for them, but for those who lived in Gaster's timeline.

 

Who could've thought something like this would happen?

 

"Humans, Monsters..."

 

She spoke, observing attentively the result of her actions; timeline 0.55-D changed, from its very foundation, the laws of its universe, she broke them herself, she was still breaking them, and reforming them, altering the past, changing the present, and of course, so would change the future. She had to admit it, this experiment seemed very...

 

Very... interesting...

 

"Servants!~ Mages! Types! Grands! Beasts!~ What kind of anomaly is this?! its wonderful, truly, truly wonderful!~"

 

The scream was even louder, ecstatic at the idea. Gaster made no sound at all, at least he couldn't talk, but just because he had no voice, didn't meant she couldn't understand him. He sat right next to her, neither him nor her willing to mess up with the timeline anymore. His dream, his mission, was completed; she had accepted his proposal, just as he had told her, they would watch something very, very interesting.

 

If only she had a soul... he was sure it would be filled with determination right now.

 

Now... all she had to do was sit back and enjoy the show.

 

"Let Frisk Dreemurr’s Grand Order... begin~"