Disclaimer: Kingdom Hearts and Gravity Falls are copyright to Disney

Note: This story is set roughly a year after the end of the original TV series, so all Gravity Falls characters are a year older.

Prologue

Dive into the Heart

He was falling… falling through the vast void of space, toward an unknown destination.

"I've been having weird thoughts lately…

…Is any of this… even real?"

His eyes suddenly shot open, and he found himself on the edge of the coast, the sun pounding into his eyes. He pulled his hat down, trying to shield himself from the harsh rays. Looking up at the ocean in front of him, he could just make out the shape of another boy, one he didn't know, a ways out into the water. The other boy seemed much older than him, with spiky white hair, dirty brown clothes, and dark skin. He wanted to try and say something to the other boy, but as he was taking a step, he noticed the water suddenly pull away from the shore. That could only mean…

His head shot up, confirming his concern; a massive tidal wave began to form at the far end of the ocean. The boy in the water showed no fear whatsoever. He merely turned around, revealing his sinister yellow eyes, holding his hand out for him to take. Without even thinking, he dashed towards the other boy, just as the wave came crashing down on him.

He spun around under the waves, staring ahead at the older boy, still unfazed, hand still held out for him to grasp. He tried to swim over to the older boy, but the current was too strong. In mere seconds, he was swept away, carried rapidly towards the surface.

He gasped for air as he broke the surface, shaking the water out of his hair. His attention turned back to the shore, where he found a girl the same age as him standing there, waving and calling out to him. Elated, he waded through the water over to her, a smile plastered on his face. As he reached the girl, she playfully punched him in the shoulder, grinning softly until her attention turned to the sky. Following her gaze, he discovered a figure falling towards the ocean before them. Staring closely at the figure, he realized that it was him.

Suddenly, he was in the place of his doppelganger, falling towards the sea below him. The girl reached her hand out to him in fear, her image rippling away as he broke through the surface.

He kept sinking, closer and closer to the ocean floor. He could see the bubbles passing him as he fell. Eventually, his descent began to slow down, allowing him to orient himself, his feet landing on something solid. It was at this moment that he realized something; he could still breathe. He glanced around the area, wondering what was going on. He tentatively took a step forward…

…and he was suddenly forced to shield his eyes as the ground below him erupted into a massive flock of doves, revealing a large platform made of stained glass at his feet. The platform depicted a beauty maiden, with ebony black her, blood red lips, and skin as white a fresh fallen snow, cradling an apple close to her mouth. She appeared to be asleep. He watched as the doves flew away into the darkness, dumbstruck at what had just happened.

Suddenly, a voice rang out through the void…

"So much to do…" He looked around wildly, searching for whoever was talking. "…so little time. Take your time. The door won't open just yet." What the heck is this voice talking about?

"Now, step forward. Can you do it?"

What, now they're asking if he can walk? Almost insulted, he strode to the center of the platform, and waited for the voice to speak up again. He looked up to the dark sky, expecting some sort of sign. From his peripheral vision, he saw a spark of light in front of him.

He looked ahead, and for a split second, he could have sworn he saw a boy with windswept, caramel brown hair before he disappeared. In his place, a small pillar appeared near the top edge of the platform. He turned in place to see two more pillars appear around him.

"Power sleeps within you…" The voice spoke up again, as three weapons appeared, one above each pillar; a sword, a shield, and a staff. "…if you give it form… it will give you strength. Now, what will you choose?"

He glanced uneasily at each weapon, wondering what he should choose. Glancing at the shield, he tentatively walked over to it, and picked it up, holding it in his hands.

"The power of the Guardian. Kindness to aid friends. A shield to repel all. Is this the power you seek?"

Kindness was definitely one of his better qualities, but he thought the "shield to repel all" bit sounded cowardly somehow. Still unsure, he put the shield back, now going over to the staff.

"The power of the Mystic. Inner Strength. A staff of wonder and ruin. Is this the power you seek?"

This certainly appealed to him. Inner strength meant powers of the mind, and powers of the mind meant cunning, something he had in spades. Looking up, he spoke for the first time since his arrival.

"Yes." The staff suddenly burst into a flash of light, seeping into his chest.

"Your path is set. Now, what will you give up in exchange?"

What? Now he had to sacrifice one of these things? He glanced at the sword, deciding he should at least know the entire package before he made his final decision. He went over to the sword and picked it up.

"The power of the Warrior. Invincible courage. A sword of terrible destruction. Give up this power?"

He had to admit, the part about invincible courage sounded pretty badass, but the terrible destruction thing gave him reason to consider giving it up. Thinking back to the shield, he looked up to give his answer.

"Yes." The sword disappeared, the particles of light drifting into the void.

"You have chosen the power of the Mystic. You've given up the power of the Warrior. Is this the form you choose?"

"Yes, it is," he answered with conviction. He stumbled off the pillar as it suddenly started sinking into the platform. Looking around, he was horrified to see that the platform was breaking apart. Before he could react, the platform had shattered, sending him plummeting into the darkness.

Eventually, another platform came into view underneath him. Like the last one, it was made of stained glass, but it depicted a blonde woman in a silken white dress. She, too, appeared to be asleep. As he landed on the new platform, he noticed a blue haired young woman standing in front of him, but a split second later, she was gone. Before he could think about it, there was a flash of light in his hand as the staff he chose earlier appeared in it.

"You have gained the power to fight." The voice spoke up again. He gazed at the staff in his hand, giving it a few test swings. He took a small battle stance, and began shadow boxing with his weapon. He panted lightly as he finished. He suddenly noticed small shadows appearing on the ground in front of him.

"There will be times when you have to fight." The shadows suddenly rose from the ground in front of him, morphing into small, black creatures with glowing yellow eyes and crooked antennae on their heads. He was terrified at what was now before him, but quickly steeled himself, and began hacking into the monsters with his staff. He didn't noticed one of the creatures melt into the shadows and slink around him. "Behind you!" Heeding the voice's warning, he twisted around on his heels, splitting the monster clean in two. Before he could do anything to the remaining monsters, they sunk into the platform, causing dark pools to appear across it. He suddenly found himself sinking into one of the pools. He struggled to get out, but it did him no good. He felt terrified for his life as his vision went black.

His eyes flung open, and he found himself in front of an old shack in the middle of the woods. He noticed three people positioned around the shack's porch.

"Hang on. The door won't open just yet…" He heard that voice again. "Now, tell me more about yourself." He didn't need much to figure out how he would do that. He walked over to the closest person, a teenage girl with long red hair.

"What's most important to you?" She asked him. He looked on as he contemplated his answer.

"My friends," He finally answered.

"Is friendship really such a big deal?" was her response. Ignoring that comment, he went over to the next person, a chubby man in a green shirt.

"What are you most afraid of?" he asked. This one, he actually had to analyze for a while before he could respond.

"I guess… being indecisive."

"Is being indecisive really that scary?" He went over to the final person, an old man in a black suit and a red fez.

"What do you want out of life?" the old man asked. This one was a no brainer.

"To see rare sights."

"To see rare sights, huh?"

"You value friendship. You're afraid of being indecisive. You want to see rare sights. Your journey begins at midday. Keep a steady pace and you should be fine."

"Sounds about right."

"The day when the door will open is both far off and very near." He didn't understand what the voice meant by that, but before he could think about it, his vision went white. When it cleared, he found himself back in the dark void on yet another stained glass platform. This one depicted yet another sleeping woman. She was surrounded by thorny vines, and wore a red dress, clutching a rose to her chest. She seemed as beautiful as the last two women he saw on these platforms. Her hair was golden like the sunshine, her lips could shame a rose, and her sleeping face held an expression of bliss.

He looked up to briefly see a tall, muscled young man before he disappeared, leaving behind more of the black creatures he fought earlier. Having now become familiarized with their patterns, they were disposed of quickly.

When the last monster was disposed of, he noticed a spotlight appear in the center of the platform. He watched as it traveled to the edge of the platform, where is revealed a long, twisting ramp made of stained glass panels, leading to another platform in the distance. With no other leads, he proceeded up the ramp, never noticing the panels disappearing behind him.

Soon, he came upon the new platform. This one showed a beautiful, brown haired woman in a yellow dress, once more asleep, but behind her, he could see the image of a massive, brown furred beast. A strong light shined on the center of the platform. He walked slowly over to it, wondering what was supposed to happen now.

"The closer you are to the light, the greater your shadow becomes." At the voice's words, he turned around to see that, indeed, his shadow was now massive. Suddenly, right before his eyes, his shadow rose up from the ground, beginning to morph into a different shape. He began to slowly back away from whatever this thing was, watching a pure black hand flex itself in the free air, staring at the twisted foot that planted itself on the ground. Terrified, he turned tail and fled, only to stop as he reached the edge of the platform. He turned around, staring at a massive monster, its head wrapped in a mass of black tentacles, leaving only its glowing yellow eyes visible to him. Smack dab in the middle of its torso was a giant, heart-shaped hole that he could see clean through. "But don't be afraid…" The voice spoke up again. He whipped out the staff, deciding he wasn't going down without a fight.

The battle was long and hard, but eventually, he got the giant on the ropes. Before he could deal the final blow, his staff suddenly disappeared. In his brief moment of distraction, the monster brought a fist down in front of him. He stumbled back, falling into a pool of darkness, which rose up to entangle him.

"But don't be afraid…" The massive monster loomed over him as the darkness ensnared him. He reached a hand out, hoping someone, anyone, would rescue him. "…and don't forget!" He could stare ahead, absolutely terrified as his vision went black.

"You are the one… with their blood in your veins…"