Prologue

"Is it working?" a voice shouted over the roar of the portal.

"What do you think?!" another called in response.

A blinding bluish light filled the room. Neither of the young men bathed in its cold glare could see a thing, however, they had spent so much time in the bunker that they didn't need to in order to know where they were going. As the two approached the entrance, its suction grew ever stronger.

After a certain point, the man in front was no longer able to resist the powerful inhale of their machine.

"We did it! Promise to meet me on the other side, alright?" he said, jumping towards the opening.

"Promise!" the other cried back, but his brother was already gone.

Before he could get pulled through, a cackle twinged with slight malice reverbrated throughout the room. The brother who was left glanced around, daring to open his eyes despite the fatally bright light.

"Brother?!" he screamed, twisting his head in search of the noise.

Whatever it was laughed again, and with its final outburst, the portal blinked shut.

"STANLEY!" The man's voice tore itself from his vocal chords, ripping his throat utterly raw.

His surroundings were now pitch black after such a blazing radiance, so the only thing separating the floor from anywhere else was the tears of regret that crashed, one at a time, on the cold, hard ground.

Finally, he could get his brother back. It took him over 40 years to fix with his inadequate funding and lack of help from his brother, but he still did it.

Now he just had to step through and fulfill his promise. After they had been reunited he planned on returning with the both of them, safe and sound. After all, he was just ripping a hole in the spacetime continuum and crossing an interdimensional wormhole to get to another universe. What could possibly go wrong?

But even if his brother didn't want to return, he still would. He would respect any decisions his brother had made in terms of leaving or staying. No matter how much he wanted to, though, he had to return. His great niece and nephew were staying with him for the summer, and he couldn't afford to lose them as well.

The blue light again filled the room, bringing with it a wave of memories from that night crashing down on him. He thought he was just imagining it when that laugh resounded once more. It was so real, he paused in his tracks and glanced around the room, reminiscent of that night so many years ago.

Too late he realized it indeed was real, and he had missed his chance to dive through the entrance.

Rather, the menacing opening spat out something that looked vaguely like a group of odd people, although it was somewhat challenging to tell based on their mangled silhouette. With that, the light flickered out of existence.

The man stood there dazed, staring at his machine, confused as to what exactly just happened.

As his eyes adjusted, he was able to make out that the writhing heap on the ground was, in fact, people. There were about six or seven of them, all wearing strange black and red outfits, and a few who had quite peculiarly shaped bodies.

Slowly, they all stood up, except for one, who appeared to be asleep. His incredibly large body was on another that resembled a palm tree. That one was squirming ceaselessly under the giant in order to escape being crushed to death. Eventually, the giant rolled over and the tree jumped up and started kicking the sleeping one's arm while yelling profanities at him.

The people began to realize that they weren't alone in the room. The exchanged surprised glances before the little kid of all people started walking towards him. He couldn't have been older than ten years old, but his face seemed the most mature. Upon reaching him, the young boy extended a hand.

"I'm Pride, and these are my siblings. Who are you and do you have any idea what we're doing here?" the kid said calmly, sounding both bored and afraid at the same time.

The man shook his hand. He was still in shock, but he was able to sputter out that he was Stan Pines and sorry, he had no clue as to who they all were or why they had come out of his portal.

Pride eyed him suspiciously, but said nothing more as he returned to his family.

Just as the palm tree opened his mouth, something profoundly unexpected to Stan happened. The portal turned back on.

A/N: YAAAAAAAAAAAY! Short prologues! Anyway, I just watched Brotherhood because everyone says I should and that it's better than the first series, which I've already seen. It wasn't. But I did really like the homunculi better, but Ed was more annoying. So yeah :/ There's more and I could rant on, but if anyone somehow magically happens to read this then you're probably not reading this to hear me complain about anime. So I wanted to do a fic for FMA, but I couldn't think of anything, and then I did, and then I decided to make it better by making it a Gravity Falls crossover. Ed, Al and those guys might show up later, and there will be more backstory with Stanley and stuff so just remember that REALITY'S AN ILLUSION THE UNIVERSE IS A HOLOGRAM BUY GOLD BYEEEEEEE!