Hey, everybody, Jack of Knaves here, coming at you with a Deltarune-Undertale crossover, set in the Glitchtale AU to be more precise. Admittedly, this is a concept that I have been thinking about doing for quite some time, and now I have decided to put it to work.
So, here's what you need to know. From the Deltarune side of things, this follows the Snowgrave Route, so Berdly is a popsicle thanks to Kris and/or Kris' Soul and Noelle, and that will also play a part in this story as well. Plus, having another spellcaster, especially one capable of freezing a person solid, would be extremely beneficial for the group. Although, I think against the likes of Betty Noire and the like, Snowgrave would be a delay tactic at most. Granted, it would be a good while before she does break out on her own, but I think, as an entity that has survived for eons, Betty and Akumu would ultimately break out on their own… and that's if they weren't working alongside the Roaring Knight.
Indeed, I fully plan on having the Roaring Knight become one of the main villains alongside Betty Noire and any other villains I can come up with during the bigger and better Fun Gang's adventures through the new Dark Worlds that the Knight creates in the hopes of bringing about the Roaring. Should be fun, right?
I do have other things planned, but that will have to wait, as AO3's author's notes only allow for a limited number of characters. Let's get this show on the road!
DISCLAIMER:
THE FOLLOWING FANFICTION IS A NON-PROFIT PROJECT, SET IN AN AU OF ANOTHER, FAR SUPERIOR NON-PROFIT PROJECT. UNDERTALE, DELTARUNE, AND ALL ASSOCIATED PROPERTIES ARE THE TRADEMARKS AND PROPERTIES OF THE ANNOYING DOG AKA TOBY "RADIATION" FOX. THE GLITCHTALE AU, ITS ORIGINAL CHARACTERS, AND ASSOCIATED CONCEPTS AND PROPERTIES BELONG TO CAMILLA CUEVAS, NYXTHESHEILD, AND ALL OTHER ASSOCIATES WHO WORKED ON THE GLITCHTALE AU FAN ANIMATIONS THAT THE AUTHOR CAN'T REMEMBER RIGHT OFF THE TOP OF THEIR HEAD, BUT EXIST NONETHELESS. THE EVENTS OF THIS FANFICTION ARE CANONICAL TO THIS AU OF THE GLITCHTALE AU ONLY. UNLESS YOU DIDN'T LIKE THEM, OR THEY REQUIRE REWORKING OR MODIFICATION FOR SOME REASON. IN THAT CASE, IT WAS ALL JUST A DREAM.
Chapter One
An Unexpected Malfunction
The Underground-Snowdin-Sans' Workshop
Sans, a short skeleton wearing a blue hoodie, black shorts, and pink fluffy slippers, was working diligently an a machine of some sort, an uncharacteristically determined look on his face.
Nearby, a creature that resembled a talking yellow flower not dissimilar to the sort one would find in a children's cartoon watched on with an annoyed expression on his face. In another life, this creature would have been Asriel Dreemurr, scion of the Royal Family of the Underground, and heir to the throne, until a dark turn of events resulted in his death and subsequental rebirth as the creature he was now. Now, he was Flowey the Flower, and he was nothing short of a living nightmare, to put it lightly.
Laying under a blanket nearby was a teenage human boy with tanned skin and shoulder-length brown hair wearing a blue and purple long-sleeved shirt, black jeans, and black boots. Hovering above the human was a red, empty heart-shaped object. This was Frisk, and under normal circumstances, their Determination-trait soul would have allowed him to have total control over the timeline, able to RESET, SAVE, and CONTINUE, as well as granting him a variety of other combat abilities. Now, however, his Determination had been extracted from their soul, rendering him weak and powerless.
To better understand how this situation came about, one must first look back to the beginning. For thirty long years, Frisk had been resetting the timeline after achieving the same "happy" ending for their adventure time and time again, and getting increasingly bored with it all the while, even enabling Hard Mode in the hopes of shaking things up. In the end, however, it was a fruitless endeavor, and ultimately, Frisk decided to just up and kill everyone and commit genocide, as though all the friends he had made were nothing more than toys.
Ultimately, at the end, Frisk had to face Sans in a fight to the death, and was killed multiple times for their trouble, though his Determination and ability to SAVE his progress allowed him to return from the grave time and time again to challenge Sans, before the horrendous guilt finally ate away at him enough that Frisk decided to abandon his murder spree and RESET the timeline.
However, what Frisk had failed to realize was that as he continued his "Genocide Run," he was unwittingly calling back someone known as Chara, whom many monsters in the Underground had mistaken Frisk for, and was apparently the first child who fell into the Underground after the Barrier that seperated monsters from humanity was created, and was adopted by the Royal Family alongside Asriel. The more lives Frisk took, the more he lost himself and became Chara, who was decidedly not human anymore, but rather a demon.
When Frisk attempted to RESET the timeline and abandon his Genocide Run, Chara assumed complete control of his body and would have killed Sans had Frisk not broken free, sacrificed himself, and given Sans his soul, allowing the skeleton to finish off Chara and RESET the timeline, undoing Frisk's crimes and bringing back those lost because of him.
Unfortunately, though those who had died had been brought back, the damage done to the timeline itself was irreparable. Thirty years worth of resets, Hard Mode, and an aborted Genocide Run were the perfect ingrediants for causing things that no one wanted to have happen to occur. In all honesty, Sans was surprised the demented puppetmaster that was his Error counterpart, or someone from the same universe, wasn't trying to purge their timeline, it was so glitched up and distorted.
And sure enough, just as Sans had thought, something bad that no one wanted to have happen ended up happening, in the form of Chara Dreemurr, now a full-fledged demon, returning, his new existence fueled by pure Determination taken from the Amalgamates buried within the depths of the True Lab. To make matters worse, despite the combined efforts of Sans and Flowey, Chara managed to use Doctor W. D. Gaster's Determination Extractor to siphon Frisk's Determination and absorb it, giving him complete control over the timeline.
With their backs against the wall, Sans and Flowey retreated to Snowdin with the weakened and powerless Frisk in tow. Upon arriving at Sans' workshop, the skeleton immediately got to work on his pet project, the very machine he and Flowey were working on right now.
Groaning, Frisk lifted his head up and looked to see what the flower and skeleton were up to. Feeling Frisk's eyes on them, Sans and Flowey turned towards the young human.
"Hey… feelin' better?" Sans asked gently.
"Not really…" admitted Frisk. "What are you guys working on?" he asked.
"I'm tryna fix something here at the moment," said Sans, before turning his attention to Flowey. "Hey, Flowey, could you pass me the wrench from over there?" the skeleton asked, pointing in the direction the aforementioned wrench was in.
"Do I look like your stupid assistant?" snapped Flowey. "Get it yourself."
Sans' left eye glowed a bright blue while his right looked as though its socket was completely empty. "Please," the skeleton said, his voice a clear indication that it was not a wise idea to test him after the day they'd been having.
Heaving an irritated sigh, Flowey slinked over to where the wrench was. "Yeah, sure, whatever," the demonic flower grumbled as he picked up the wrench. "Take your stupid wrench!" Flowey said as he chucked the wrench at Sans, who effortlessly caught it.
"Thank you," Sans said as he continued working on the machine.
As Sans continued tinkering with the machine, Flowey took a glance at Frisk, who had climbed out of bed to get a better look at what Sans and Flowey were up to. Or more specifically, the flower took a glance at the human's empty soul that floated above their head.
After a few moments, Sans stopped working on his machine. "Alright, it's done," he said as he stood up and grabbed a nearby remote. "Let's hope it works this time…"
That caught Flowey's attention. "Wait… 'hope?' 'This time?'" he asked Sans, confused.
"How many times have you tried this before?" Frisk asked Sans.
"Eh, just a couple hundred times," Sans said with a shrug as he pressed the button on the remote. "But… if that demon child Chara managed to get back on his own… then I'm pretty sure I can bring him back…"
"'Him?'" asked Frisk, confused as the machine began to emit light that steadily began to grow brighter and brighter.
"You'll see in a moment. But, uh… you should probably shield your eyes a bit," said Sans.
Frisk and Flowey both shielded their eyes as the light coming from the machine began to glow brighter than their eyes could handle. Finally, with the brightest flash of light of all and a whooshing sound, Frisk and Flowey opened their eyes to find a smokey mist billowing out of the machine as a figure began to emerge from the mist.
It was another skeleton monster, tall like Papyrus, slender with what appeared to be two cracks in his head, one running up from his right eye, the other running downwards from his left eye. Both of his hands had a circular hole in them, as though a piece of them had been cut out. He wore a black coat with a dark gray turtleneck underneath, dark gray slacks, and black dress shoes.
"Heya," said Sans.
"Heya," said Doctor W. D. Gaster, Sans' father, creator of the CORE, and the original Royal Scientist, before cracking a smile. "Did you… mist me?" he asked Sans, who chuckled.
"Let's 'a-void' the jokes for now…" said Sans, a soft smile on his face. "We got a huge problem at the moment. Chara Dreemur's back, and he's taken control of the timeline from Frisk. Needless to say, your help will come in handy," explained Sans.
Flowey groaned and rolled his eyes at the two skeletons. "Your jokes are disgusting…" he grumbled, before something caught his attention. "Hey, Smiley Trashbag! Do we need to worry about that?" Flowey asked, pointing at the machine Gaster had just emerged from.
"Huh? Worry about what?" asked Sans before seeing what had caught Flowey's attention.
The machine Sans had just used to bring back his father was going nuts, shaking side to side like a leaf in the wind as electricity sparked around it, even throwing off bolts of lightning around the room.
"This isn't good… get down!" said Gaster as he called upon one of his hand-shaped weapons, this one with a green core, and used it to form a protective shield around himself, Frisk, Sans, and Flowey just in the nick of time as the machine exploded, pieces of it flying in every direction.
However, parts of the machine weren't the only things flying from it. Four decidedly humanoid-shaped entities were sent flying into the far wall, the biggest, most brute-like of them actually leaving a crater shaped like them in the wall before falling out of said crater and onto the ground.
As the room settled down after the explosion, Gaster dropped his shield so he and the others, except for Flowey, could get a better look at what, or who, had just come flying out of the now-destroyed machine and into their midst, and see if they needed medical attention.
Needless to say, they were quite surprised to find that it had been three monsters and a human boy, all unconscious, that had been flung out of the machine that was now lying in ruins.
One of the monsters was a female humanoid reindeer with flowing blonde hair wearing a a red and green checkered sweater with a grey romper underneath. Firmly fixed onto her finger was a ring made out of what looked like metal thorns, reeked of powerful magic, and seemed quite painful to remove and put on.
The second of the monsters was female as well, and was clearly a brute, plain and simple. She had purple skin, shoulder-length black hair, a dark purple shirt with a white undershirt, tattered blue jeans, and purple and white sneakers. This monster honestly made Frisk a little nervous, as she looked as though she could bite one's face clean off.
The third monster of the group was admittedly something of a surprise. Although Frisk and the others thought he was a girl as well, closer examination revealed that not only was he a boy, but that he was a dead ringer for the late Prince of the Underground, Asriel Dreemurr, wearing green-rimmed glasses, a green robe with a pink scarf wrapped around his neck, and lying nearby was a matching green hat that seemed much too big for him.
I miss being fluffy, lamented Flowey as he looked at the doppelganger of the monster he used to be. I am so, so sick of being a flower… so sick of being numb… I just want to be Asriel Dreemurr again… more than anything…
The goat monster's resemblance to the late Prince aside, out of all four of these new arrivals, the human of the new arrivals really threw them all for a loop. He looked exactly like Chara Dreemurr back when he had been a human. He was even wearing the same green and yellow long-sleeved shirt, brown pants, and black shoes as Chara. However, the shaggy black hair that almost covered his eyes, and the tanned skin reeked of Frisk as well.
Speaking of Frisk, he couldn't help but feel as though this new human was familiar, like he was a long-lost family member that he had once been joined at the hip with. As for Sans, he felt as though he had "befriended" the human's mother, if one were to understand the meaning.
"We should take them inside your house, Sans, and examine them for injuries while we wait for them to wake up," said Gaster. "And personally, I would like to not only know why exactly the young goat resembles the late Prince Asriel, but why the human looks so much like both Chara and our young friend here," the doctor added, gesturing to Frisk as he spoke.
Flowey rolled his eyes in annoyance. "Ugh, seriously? We're gonna play doctor for four kids hailing from scenic who-knows-where while Chara has complete control over the timeline, and is poised to erase this world and everything and everyone in it at any moment? We don't have time for this!" he said.
"Eh, it's not a problem," said Sans with a shrug. "The only way Chara could possibly amass the power needed to erase this world and the timeline is if he were to slaughter literally every monster in the Underground, and considering that his existance his entirely fueled by Determination he leeched off those Amalgamates down in the True Lab, something tells me he won't be trying that. That demon child would need to find another way, and something tells me he would need the aid of an outside force to do it. We should be fine for now."
On that note Sans used his psychokinetic powers to haul the three monsters and the new human inside his house proper to receive care for any injuries they might have sustained. Following closely behind them, Doctor Gaster's mind racing at a thousand miles an hour as he dwelt on these four new arrivals.
He had a funny feeling that things were about to get very, very, interesting…
And thus concludes the opening chapter! If you guys liked what you saw here, then be sure to fave, follow, and review, and be sure to check out my other works as well, every little bit helps! And join us next time as Frisk and the gang get a proper introduction to the Fun Gang! See you then!