This is an installment in the Omniverse. The Omniverse is a linked world of fanfic stories. All Omniverse stories are marked in the description as [Omniverse Installment] or [Omniverse one shot]. I release them in chronological order, so for the full list, you can just go to my full story list. This story takes place in the year 1999.
Also, before this story begins, I'd like a bit of confusion before it arises. In the Omniverse timeline, the full events of Gravity Falls Seasons 1 and 2 take place before this story, the only changes being made is to the technology. So really, just no smartphones. This is, after all, a linked universe of stories, and this story, any story really, is just a small part of a larger timeline, and everything needs to fit together on a linear timeline without any problems.
Now that I'm done word-vomiting, let the story begin!
Today had been a slow day at the mystery shack. Stanford and Stanley Pines had not yet returned from their boat voyage, so Soos, Melody, and Wendy had been running the mystery shack. There we're about ten people visiting, and, as has been usually happening on Mondays, the Northwests were trying to "invest" in the mystery shack. "hey Wendy, did you see this thing in the newspaper this morning?" Soos asked.
"no, I don't really read the paper" Wendy replied.
"oh, well apparently a year ago today, some teenagers went on vacation in a cabin down in Tennessee, and one of them went mad and chopped the others up with an ax. They call him the 'Tennessee Killer"
"huh" Wendy said, as if to say "interesting", but was to distracted by her magazine to actually respond with words.
A man walk into the building. He was wearing a red long sleeved button-up shirt, brown jeans, and work boots with some of the steel exposed in the toe. But the ting that caught everyone's attention was the fact his right hand was missing. He walked over to the check out where Wendy was sitting and rested his stump on the counter. He leaned in close and in a hushed tone said "has anyone around here been acting unusually aggressive?"
Before Wendy could respond, they were distracted by a couple of guests at the other end of the shack. "Don't touch my son again"
the man who was getting yelled at let out a demonic screech, baring his large, sharp teeth. The one handed man ran out of the building. "come back and help us, you coward! You were the one asking about this!"
the creature threw the woman who was yelling at it across the room. She landed on the pot card rack. The man returned, holing a Grey duffle bag and a double barrel shotgun with the barrels shortened. "why don't you pick on someone your own size" he said, taunting the monster.
It charged at him, attempting to bite into him. He shot it in the chest twice, causing green blood to leak out of it. The man reloaded his gun and aimed it at the creature's face. "this is gonna hurt" he said. The creature screamed at him. He fired both rounds of his shotgun, causing the creature's head to explode. He blew the smoke away from the barrels, which made a ringing noise as his breath resonated inside the barrels. " who even are you?" one of the visitors asked.
"I'm James Holt, and right now, your greatest hope for survival"