It was a day like any other. Mystery twins Dipper and Mabel Pines were just getting up and about to eat breakfast. Dipper was deciphering something in the mysterious red journal marked with a six-fingered hand with a three on it. Mabel was trying to pick out all the nasty parts of her cereal, so only the marshmallows were left. She threw everything non-marshmallow to waddles, who happily ate them.
"Gah! Why can't they just make a cereal without all this stuff in it?" Mabel said. Dipper, too preoccupied with the journal, just nodded and said "Mhm."
"Dipper, c'mon, stop looking in that old journal and help me pick all this out!" She yelled at her twin. He lifted his head up from his book and looked at her.
"Mabel, I'm trying to-" He paused and glanced at the book. "Wait a second… Mabel, that's it! I just have to take out everything that doesn't make sense... I got it!" Dipper jumped up from the table and ran upstairs.
"Dipper, what are you talking about?" Mabel yelled, looking around the corner and up the stairs. She ran up them after her brother. He was in their room, dressed out of his pajamas, and tying his shoes.
"Mabel, get ready! I have to go get Wendy and Soos." He ran back down the stairs to get them. Mabel put on a white sweater with a blue pine tree on it, the same symbol that was on Dipper's hat. She didn't really want to wear it, but all her other sweaters were dirty or missing and she didn't have the time to look for them. She put a head band on, slipped on her black flats and ran after her brother.
"This is probably something to do with the stupid journal again…" She thought to herself.
When Mabel got outside, Dipper had already gotten Soos and Wendy. They were all sitting in the golf cart, Dipper at the wheel and Soos and Wendy at the back.
"Mabel, get in! We have to go right now!" Dipper said sounding frantic. Mabel hopped in beside her brother. Dipper slammed his foot on the pedal and drove into the forest.
"Hey, little dudes, where are we going?" Soos asked.
"Yea, I was wondering the same thing." Wendy added. Dipper handed the journal to them opened to a page with a drawing of two massive trees standing side by side on it. They both had one large limbs sticking out near their trunk that spiked out and connected to one another by a wooden circle. Thousands upon thousands of branches jutted out from the circle, and even more were hacked off.
"The twin pine trees. Said to exist in the heart of the forest, these two trees are said to tell a prophecy of two twins, a boy and a girl, who are children of omniscience itself. Both were born with the ability to see and be seen by the wonders of the forest, something extremely rare among mortal children. The boy was also granted the ability to decipher almost any code and know almost anything, while the girl was able to use magic and bend time to her will. Both are said to be immortal, but I cannot confirm whether or not this is all true. All I know is that the trees do exist, and do seem to be magically entwined to all of Gravity Falls. There seems to be some sort of barrier around the tree that only allows people it chooses to pass through, while anything else that attempts to pass it is viciously stabbed by the trees surrounding it. I don't plan on risking an attempt to pass it myself, and I urge you to not risk it either." Mabel read aloud.
"Dipper… this doesn't seem like a good idea. Maybe we should just,"
"No! We have to go! I need to know… I have to know!" Dipper interrupted. He had a determined look on his face as he drove the golf cart.
"But why do Wendy and I have to come with?" Soos asked. He still wasn't sure what was going on, but he had a feeling that he shouldn't go wherever Dipper was taking him.
"So I won't seem crazy when I come back and tell everyone what happened."
They had been driving for about half an hour now. Everyone was getting restless and kept asking how much farther it would be. Every time, Dipper would just say 'we're almost there.' Out of the blue, a chilly wind blew at them.
"Did you guys feel that?" Wendy asked.
"Yea, dude. It was super-creepy." Soos agreed. Mabel turned around with a puzzled look on her face.
"What are you talking about? I didn't feel anything. Dipper, did you?" Mabel said. Dipper grinned and shook his head.
"That means we're close! Hang on, guys." Dipper put the pedal all the way down, making the cart swerve. A clearing came into view. It seemed to be omitting some sort of blue light. The cart suddenly stopped, and Mabel almost flew out the front.
"Dipper, what the heck?!" she screamed. But Dipper wasn't listening. He had already gotten out of the golf cart and ran towards two extremely tall and slender trees. They looked exactly like the ones in the journal, entwined branches and all. Two profile views of children were engraved into their bark. One child had short hair, the others was long. The circle where the two largest branches had a very simplistic eye engraved into it, like some sort of weird Cyclops thing.
"Guys, this is it!" Dipper exclaimed, smiling widely. He and his twin sister gaped at the object with much curiosity, while Soos and Wendy stood still. The tree was frightening to them. Very frightening.
Dipper slowly walked towards the blue force field, hand stuck out. His eyes were the size of platters.
"Dipper, no!" Mabel yelled to her brother, running to pull him away. But it was too late. Dipper was suddenly pulled through and landed on the other side.
"Dipper!" Mabel yelled. She jumped after him, brown hair flying behind her, but she never made it. Dipper turned his head back just in time to see his sister be impaled by thousands of branches all through her body, through her legs, arms, head, and torso. The only thing that seemed to be left intact was her left eye. Blood flowed down her and onto the forest grass, and turned her white sweater a sickly red.
"Mabel!" Dipper yelled. He ran towards the force field and tried to jump through, but only collided with it and fell backwards. He got back up and started to bang on it and kept yelling his sister's name.
"Mabel! Mabel! No no no, Mabel!" Dipper tilted his head down, crying. He didn't want the others to see him like this. He quickly glanced over at Soos and Wendy, just to see where they were. Both seemed to be stopped mid-gasp. Dipper lifted his head up to get a better look. Sure enough, they weren't moving at all. It didn't even look like they were breathing. Now that he looked, not even the trees were shaking in the wind like usual. High above the clearing, two birds were completely still. Now Dipper knew something was wrong.
"Did… time stop?" He whispered to himself. "But… that's impossible…"
"It's funny how dumb you are."
Dipper jerked his head up. He knew that voice, that expression…
"Bill!" He yelled, turning around. But this couldn't be Bill, could it? Before him was a very tall man with blonde hair, a yellow suit with long coattails, black shoes, tie, top hat, and cane, and an eye patch over his right eye. Dipper stood there, not sure whether to start yelling accusations at him or ask who he was.
"Dipper. Glad you could show up." Bill said. "Yes, I am Bill, and yes, I did stop time."
"Bill, why are you doing this?" Dipper asked. Bill walked over to where Dipper dropped the '3' journal and picked it up. He flipped to the page that had the twin pine trees on it and showed it to Dipper.
"I'm sure you've seen this before. The twin pine trees, said to tell a sort of prophecy." He tossed the book back at Dipper, who caught it and tucked it back under his arm.
"As you probably didn't notice, since, you know, you're pretty dumb, that page wasn't always in the journal. One night, while you were sleeping, I added it to your book." Bill said, pacing back and forth on his long, elegant legs. His cane hit the ground with a dull thud with every step.
"But that doesn't make any sense. Why would you-"
"Because I needed to talk to you, and I knew that you wouldn't meet me if I just asked you. I knew if you saw such a thing in the journal you would just have to explore it, with your extreme curiosity and all. These trees were always here, it's just that the man who wrote those journals never wrote about them. Quite the coincidence that it was this mystery he didn't write about. They're just the thing I need." Bill explained. Dipper was extremely confused at this point.
"Why do you need these trees? What are you planning, Bill?" Dipper exclaimed, pointing an accusing finger at him. Bill grinned and stood still, leaning forward on his cane.
"To tell you a story, of course. Take a seat Dipper; this is going to be long."
"I think I'd prefer to stand."
"Ok, fine, whatever. But if you pass out I'm not catching you." Bill said sighing.
"Why would I fall?"
"You'll see in a moment." Bill lifted up both legs and sat floating above the ground and cleared his throat.
"Ok, I guess I should start at the beginning of my story. I was never really born, just suddenly 'poof!' I took form in this galaxy. I had no idea what I was doing, or at least until I looked around. Behind me was a massive blue and green ball you know as Earth. It was back when nothing but bacteria and plants lived. It was boring as heck for the first billions or however-long-it-was years. I had nothing to do but sit around and stare at little squirmy things all day. Once they started to evolve and get bigger, I finally was able to have a little fun. Did you know that there used to be a type of duck with a snout like a dog and fins? Those little annoying pests kept biting me when I swam, so I got rid of them all. Anyways, I've seen everything since then happen on Earth, blah blah blah. I taught man how to survive and I gave them knowledge. I made humans the dominant race. I tried to rule over them, but they never would listen and I ended up killing them. I tried to naturally have children, but nothing any mortal woman could conceive survived past age four. They were all a little different, too. One grew into an elder and died in two years, another had a head the size of a normal baby's whole body and a body the size of a hand. So I stopped trying that. I attempted to build them from plants, but they all burnt up. For thousands of years I did nothing but test and research how to create a perfect human. Then it hit me! What if I transferred my power into two identical humans? It was perfect! So I set to work sculpting them out. Naturally it had to be a boy and a girl. It wasn't till the 19th century that I finally finished making their bodies. I'd gone through thousands of prototypes, but these two were perfect. They were my ultimate creation. But the hardest part was still to come. I had to split one very young soul in half so it would be just right. Many explosions happened there. See, splitting a soul is like splitting an atom, but ten times worse and you have a pretty good chance of causing some break in the space time continuum. Luckily I avoided that and by the 21st century, they were completely finished. I created 'parents' for them. They would raise them until they were old enough to be able to handle my magic, when they would return to the place of their creation and fulfill their destiny."
Dipper was amazed. Bill was so powerful he could mess with life and create it himself?
"Why exactly did you tell me this?" Dipper nervously asked. He wasn't sure what to expect. Was he supposed to go and find these two people and bring them to Bill?

"Because, Dipper."

"Those two children are none other than you and your sister."