Hi! This is my Percy Jackson and Gravity Falls crossover. While you're reading, keep in mind this was supposed to be a one-shot. So this chapter might be a bit funky. So, this is my story, hope you like it! There are no Slash, but maybe some slight coupling with the characters already paired in the series. There might be a few spoilers, so if you haven't read Percy Jackson or watched Gravity Falls, you will be majorly confused and things will be spoiled. You have been warned!

Leo Valdez was dreaming.

Of course this was normal if you were a demigod, but this dream was different.

Everything was black and white. Actually, more like grey. Yeah, everything was grey like the all color was sucked out of the world. The only colorful thing he was himself and this weird triangle dude. The triangle dude was neon yellow, wore a tie and a hat, and had a single eye.

"HEY SPARKS! THE NAME'S CIPHER! BILL CIPHER! AND I'M GOING TO CHANGE YOUR LIFE, KID."

Leo was confused and annoyed. He actually wanted to go to bed tonight, and here was this triangle ruining whatever sleep he was going to get tonight (curse you Gaea!). But he was also curious on what this triangle wanted, "Don't call me Sparks. What do you mean by 'Change your life'?"

"YEESH, DON'T BE SO SERIOUS, SPARKS. I THOUGHT YOU WERE GOING TO BE FUN!"

"Hey! I'm loads of fun! I'm Leo Valdez, bad boy supreme! If anyone's fun, it's me."

"ALRIGHTY, KID. WHATEVER YOU SAY. ANYWHO, I WANTED TO MAKE A DEAL WITH YOU. HAHA! I RYHMED!"

Leo instantly felt suspicious. They were in a war, and when a mysterious triangle shows up in your dreams to make a deal, it pretty much has Gaea written all over it. But, curiosity won him over. "What sort of deal?"

"OH, NOTHING BIG. JUST SOMETHING THAT COULD SAVE THE WORLD AND YOUR QUEST. WANNA SEE MY SCREAMING HEAD?" a decapitated head sprung out of nowhere and screamed. Leo yelped and stumbled backwards. Bill snapped his fingers and the head turned inside out and disappeared.

"Okay, first of all, eww. And second of all, did you say save the world?"

"HAHA! I LIKE YOU, SPARKS. STRAIGHT TO THE POINT. JUST LIKE MY LITTLE PINE TREE FRIEND!"

"Who-what-now? Actually, never mind," he didn't want to see another screaming head, "what's your deal, Cipher?"

"EASY. I WILL FINISH YOUR PROJECT IF YOU GIVE ME A PUPPET!"

"Wait. How did you know about my project?" he hasn't even told his friends about his project. How could this guy know?"

"SPARKS, I HAVE EYES EVERYHWERE. I KNOW EVERYTHING. HEY! DO YOU NEED ANY INTERDIMESNIONAL SUGAR?" a colorful sugar bag appeared out of nowhere, and all the grains seemed to be blowing up each other.

"Err, I'll pass. If Piper figured out I ate sugar when I was supposed to be in bed, she'll blow a fuse!"

Cipher shrugged, "OKAY, SUITE YOURSELF!" The bag disappeared in a random tiger's mouth. Then the tiger exploded.

"Umm… okay? Anyways, what do you know about my project?"

"NOTHING MUCH. JUST THAT YOU PLAN TO REBUILD YOUR DRAGON INSIDE YOUR SHIP, AND IF YOU MESS UP, YOUR WHOLE SHIP WILL SPONTANIOUSLY COMBUST!"

"So… pretty much everything?"

"YUP!"

Leo ran his fingers through his hair. There was a good chance that the ship would explode even if he didn't mess up. It would be so much easier for him to make the deal and get things over with. No risks of killing everybody on the ship. But there had to be a catch. "What do I need to do?"

"I JUST NEED A PUPPET, THAT'S ALL."

"A… puppet?"

"YEAH, YOU KNOW, A PUPPET. SOCK PUPPETS, WOODEN PUPPETS, TIME BABY PUPPETS. THE WORKS. I THINK THERE'S A SHOP ON YOUR NEXT STOP."

"Why would the Pyramid of Giza need a puppet?"

"HEY, AS A DREAM DEMON OF PURE ENERGY, IT GETS AWFULLY BORING IN THE DREAMSCAPE. PUPPETS ARE HILARIOUS!"

"Yeah, yeah, puppets. And if I make the deal, you'll finish my project with Festus?"

"OF COURSE! IN FACT, BEFORE YOU FILL YOUR END OF THE BARGAIN, I'LL FINISH MINE! I DON'T USUALLY DO THAT! SEE HOW NICE I AM?"

Leo rolled his eyes, but still felt uneasy. He could be working for Gaea, but Gaea's dreams usually don't act this way. It's usually Ha-ha-ha-ha-ha-You-are-nothing-but-a-puny-ant-Leo-Valdez-You-and your-friends-will-fail-and-I-shall-rule-the-world-Ha-ha-ha-ha-ha-ha type of thing. This felt different somehow. "So, you promise to hold side of the deal?"

"CROSS MY BOW, AND HOPE TO DIE."

"Okay then," he held out his hand, surprised that it became surrounded in blue fire, but ignored it. This was a dream, after all. Bill extended his hand (also in blue fire) and shook it. Leo crossed his arms, "Now do your side of the deal."

Bill snapped his fingers, "DONE! NOW TIME FOR YOURS!" he reached forward and grabbed Leo. Leo felt Bill enter his body and share his mind. Leo yelped in surprise. The world returned to normal color and they were suddenly back in the engine room.

Leo stood up uneasily, holding his head. "What the Hades just happened?"

"HEY SPARKS!"

"Ahhh!" he jumped three feet in the air, but found nobody near him, "Where are you Bill?"

"GET A MIRROR, KID."

For a moment, it seemed like those words came from Leo's own mouth. Naw, that's ridiculous. No one talks through my mouth, except me. He reached into his tool belt and pulled out a mirror (the type on cars and trucks and stuff) and looked into it. What he saw nearly gave Leo a heart attack.

Everything looked normal except for his eyes. One eye was it's usual, charming, handsome self while the other was pure yellow with a pupil shaped like a reptile's. "W-what the-"

"HMM. I GUESS SINCE YOU ARE HALF GOD, I CAN ONLY CONTROL HALF OF YOU. NO BIGGY. THIS CAN BE WORKED TO MY ADVANTAGE." Those words came from his mouth.

"What's going on Bill? This wasn't part of the deal!" now, he couldn't say anything at all. In fact, he couldn't even control his body. The only thing he could do was think.

"HAHA! YOU SOUND LIKE PINE TREE! OF COURSE IT'S PART OF THE DEAL! I NEEDED A PUPPET, AND YOU'RE MY NEWEST ONE!"

"You've done this before?"

"OH YES! LOADS OF TIMES! GOOD OL' SIXER AND PINE TREE! HAHA! THEY WERE HILARIOUS TO PLAY WITH!"

"Why are you doing this?"

"LOOK, SPARKS. I KNOW WHERE TO DRAW THE LINE. WHEN OLD EARTHY COMES AND TELLS YOU TO DO SOMETHING, YOU DO IT. OF COURSE, AFTER I FINISH UP USING YOU FOR HER PLANS, I CAN HAVE YOU ALL TO MYSELF! YOUR FIRE IS DELUX!"

"You're working for Gaea?"

"WE ARE BOTH POWERFUL FORCES WITH OUR OWN PLANS ON WORLD DOMINATION. WE JUST SAW WE CAN BOTH BENEFIT FROM THIS, SO A TEMPORARY TRUCE WAS MADE. BELIEVE ME, SPARKS, WHEN I'M THROUGH WITH YOU, OLD EARTHY WOULD WISH SHE NEVER CROSSED ME!" Bill walked across the room and put his hand under the pump. His hand was squashed. "HAHA! PAIN IS HILARIOUS!"

"OW!" he screamed in his mind. His single eye watered. He felt the pain. "You'll never get away with this!" Wow, that was cliché. Way to go, Valdez.

"HAHA! YOU SOUND LIKE PINE TREE! BUT THE THING IS, SPARKS," he looked back into the mirror, directly in his eye, "I ALREADY DID!" (Cliché again!) his hand lit on fire and he walked out the door.

All Leo could do was scream.

Hi! did you like it okay? Keep in mind that as I was writing this, I was meaning for it to be a one-shot, so sorry if it's a little funky. So, yep. Leo's a puppet now. Reviews are appreciated. Please point out spelling mistakes. If you criticize, make it constructive criticism. So anyway, bye!