Notes: The events of Undertale have been bumped back a few years, from 20XX to 201X. Chara fell down sometime in 199X. Events take place after Undertale, and before Roadside Attraction from Gravity Falls. Other timeline stuff to be announced as the story goes on.

Chapter 1: Fallen Down

Once upon a time, two races ruled over the Earth: humans and monsters. They lived together peacefully. One day, a war began between the two races. Numerous were slain, but the humans were eventually victorious. They locked the monsters below a mountain with a magic spell.

Many years later...

201X

They say that those who climb the mountain never return.

However, a young child did indeed climb the mountain, and, through the power of love and determination, freed the monsters. What happened after, though? Let's take a dive in and see.

Hundreds of miles away...

A young boy is reading in a living room. It just so happens that today, August 19, will be a strange day indeed. He has moved to Gravity Falls, Oregon for the summer, along with his sister, and has been here for two months now. He is staying in a place called the Mystery Shack, owned by his great-uncle and infamous conman Stanley Pines. Recently, his long lost brother, Stanford Pines, has come back after a multi-dimensional adventure. Also, there's a dude named Soos and a laidback teen named Wendy that work there. Now, I've been explaining long enough. What is this young man's name?

BORING MCDORKFACE

Hey, now that's just mean. Try again.

DIPPER PINES

Good! That's a great name right there. This boy's name is Dipper Pines, though his real name is Mason. He's currently reading some book on a bed on his room, waiting for something interesting to happen. Suddenly, a girl wearing an extremely glittery sweater bursts through ugh the door.

"Dipper! You've gotta see what's on the news!" this girl, Dipper's sister, yells loudly.

What shall we name her?

OBNOXIOUS MORON

No! Try again.

MABEL PINES

Good. The next time you pull something funny like this, you get your naming privilege taken away. Anyway, let's continue.

"No, Mabel, I haven't," Dipper says. "This better not be another one of those weirdly popular infomercials. Bill Brisk advertising Flexible Sealant is permanently burnt into my mind." He taps two fingers to his head, further driving his point.

"No, you silly goof," Mabel says, pulling Dipper over to the TV screen. "Take a look at this!" She points. The cameras are focused on some kid speaking at a podium. They're dressed quite casually, wearing a striped sweater and some blue pants. Or maybe that's a onesie? The fandom will never know.

"So what? It's probably just some kid that invented some sweater that never gets hot or something," Dipper grumbles. Mabel's seriously interrupting me attempting to study this journal for some kid's speech? Jeez. Must be a slow day both for her and for the news.

"No! Although, that'd be pretty cool.. But still! Look!" Mabel says again, moving her finger closer to the screen. Standing next to the kid, there seem to be some... monsters? What? There seems to be some skeletons, an anthropomorphic lizard, a blue fish lady, some anthropomorphic goats, and more! It seemed that there was an entire crowd, no, a whole nation of assorted creatures standing around the stage where the kid was talking. But real monsters only came Gravity Falls. This must be some hoax or town tradition... right?

Dipper sits back, shocked. How? Where in the world did these monsters come from? Dipper thinks. He looks closer at the news caption, which reads, "Local child frees underground civilization." "Urban legend of subterranean monsters becomes true." The list goes on. Dipper stands up and runs into another room, Mabel calling him to come back and continue watching. Dipper finally stops at a door that was originally hidden behind a cabinet, but was removed after Soos discovered it. It leads to where Grunkle Ford is, hunched at a desk, tinkering with something. He was quite an adventurer and a knowledgeable scientist, being stuck traveling across dimensions and hopping planets for a few decades.

"Grunkle Ford! I need to ask you something," Dipper says.

Ford replies, "Oh, hey Dipper. What do you need?" Ford doesn't turn to him, eyes locked onto his whatever he's working on.

Dipper takes a deep breath. "I need to ask about some strange monsters, or something."

"Oh, shouldn't be too big of a deal. What's bothering you kids this time? Gnomes? Zombies? The kismoirspritice? Whatever it is, we can probably just send it to another dimension and let its inhabitants decide what to do with it," says Ford.

"Actually, no," Dipper responds. "I wanted to ask about an underground civilization of monsters. You know, like a bunch of different kinds living in it's own... society, I guess?"

Ford freezes, and slowly turns his head towards Dipper. "What do you mean, 'underground civilization of monsters?'"

Dipper, sensing Ford's tension, stutters, "I-I saw it on the news. Some kid freed a nation of monsters that a-apparently lived underground."

"Dipper," Ford sternly says, walking over to him and going down on one knee. He then puts his hands on Dipper's shoulders. "I've never told anyone about this, but... I've seen this before," says Ford.

"What?" Dipper asks, clearly confused.

"Yes. I have seen this, but not in this dimension, no," says Stanford, now standing up. "You see, as I was traveling through dimensions, I saw many different... let me say, iterations of this universe. Out in the infinite abyss of reality, there are many different universes. Most, as you can imagine, are vastly different from ours. Some, however, are very similar to ours. Many of them are almost perfect copies. Others are like out world, except another big supernatural event happens. I've seen alien women from space, battles between monster pets, and even one where you and Mabel team up with a whole crew of kids, and called yourselves the Mystery Kids." Ford laughs, but then stares off into space wistfully, almost as if remembering a certain pointy-haired alcoholic friend of his.

"Okay," Dipper states, still a bit puzzled, "so does that mean that this race of monsters has happened in most of the copies of our universe?"

"No," Ford says firmly, surprising Dipper. "Most of the other universes are without these monsters, and, as I have observed, most of them turn out completely fine. The problem is, is that the universes with our type of situation end up completely different."

"What do you mean? Does something bad happen?" Dipper asks panicked, "D-does someone die? Does-"

"Dipper, stop. I don't want you to worry. By 'completely different,' I meant that in a good way." Dipper wipes his forehead and lets out a sigh. "Although, for some reason, I sense that our universe is drastically different."

Dipper's face falls. "Grunkle Ford, what do you mean by that?" he asks.

"It's probably nothing Dipper. I'm sure that it's nothing. Yep," he says confidently, standing up, "we're going to be just fine. Now, Dipper. You should head back to your sister. She's probably wondering where you ran off to."

"Okay Grunkle Ford. I guess I'll go then."

Dipper leaves Ford's room visibly distressed.

—-—-—

Meanwhile, in another universe, a boy in blue and his friends watch the events on the screen in hushed anxiousness. Another figure, this one clothed in orange, turns to him and says, "I think that we've found another universe to save."