What if all the people at the convention turned into who they were dressed up as?

Once Becky had made sure that Sam and Dean had come to the convention, she ran up to her room and changed into her costume. She had read every book at least 60 times. She knew stuff. Well, she knew that there was stuff. She had sought out the hoodoo priestess that Sam had mentioned in The Magnificent Seven.

Now, armed with the knowledge that she had received, she mixed the ingredients—some of it pretty disgusting, and said the incantation. "Let everyone play out their fantasy, no more will anyone be a wannabe, as each one pretends to be, he or she will actually be." With that, she lit the match and dropped it into the potion. The building shook for a few seconds and then was still.

SSS

"What is going on?" Sam asked as the building stopped shaking.

"Earthquake?" Dean asked.

"I don't think so. Look."

Dean turned to follow Sam's gaze. A few minutes ago, the room had been filled with a bunch of geeks dressed up as characters out of the book. Now they were faced with the real thing. Dean counted 5 sets of him and Sam. He wondered if they were actually just like them and had all their weapons and could fight all these things. He hoped so, because this was way too much for him and Sam to handle at the same time.

"Sam!"

Sam and Dean turned around to see Jessica bounding down the stairs. "Jess?"

"I'm not sure where we are, but did you guys find your father?"

Sam just stared. He didn't know what was going on. He had a feeling that whatever it was wasn't good, but he didn't care right now. "No."

"Sam," Dean said. "Room full of monsters."

"Room full of us, too. Looks like they're taking care of things pretty well."

Dean turned around and saw that Sam was right. A Dean had just made a Hook Man disappear by shooting rock salt at it, and a Sam had just hacked the head off of a vampire. Then he realized something.

"Dude, these people are probably killing people."

"Hi there, Sammy," the yellow-eyed demon said. "I thought I killed pretty little Jessica."

"What?" Jessica asked. Who was this guy? Why were his eyes yellow?

Sam gently pushed Jessica behind him. "We need to find out what's going on?"

"What's happening?" Chuck asked, running up. "There are actually monsters here. Thank God Lillith wasn't in any of the books." Being the only supernatural creature he had actually met (besides a couple of angels), Chuck found Lillith the most terrifying of all. But as he looked around the room he realized that pretty much everything was terrifying. How did Sam and Dean do it? He certainly wouldn't seek these creatures out.

"Who are you?" the yellow eyed demon asked.

"Me? Nobody?" The yellow-eyed demon was pretty scary, too.

"He's a prophet. Wouldn't mess with him," Dean said. He wasn't sure if he wanted the archangel to show up or not. On the one hand he could probably set everything straight, but Dean pretty much thought angels were dicks and he would just obliterate everybody. Plus, he would tell Michael where he was.

The fighting was going on behind them. The rest of the creatures seemed content to fight with the fake Winchesters, Bobbys, Ashes, etc. It made Dean wonder if the yellow-eyed demon knew that they were the originals. It didn't make sense. He would have been a fake also.

"I'm not interested in him anyway. Sammy and I have some things to discuss," the yellow-eyed demon said and grabbed Sam's arm. They disappeared.

"Great," Dean said. Nothing good ever happened with Sam and demons and he didn't think a fake demon would be any better.

"I'm going to check on Becky," Chuck said. He really liked her, but unfortunately she was too into Sam to give him a second glance.

"Wait. Do you know what's going on? How we can fix it?" Dean asked as he followed Chuck upstairs, figuring if they broke the spell, or whatever, that Sam would be out of the yellow-eyed demon's clutches.

"No," Chuck said and knocked on Becky's door.

"Hey, this is the room I was just in," Jessica said. She had followed Sam's brother and the other guy, not knowing what else to do. She was a little overwhelmed to say the least.

"Do you have the key?" Dean asked.

Jessica reached into her pocket and pulled out a key. They went inside. Dean saw a bowl with smoke rising out of it and some papers next to it. He went over to investigate it.

"What is it?" Chuck asked.

"Becky cast a spell to make everything here real. Everybody turned into what they dressed up as. Apparently before she cast the spell, she dressed up as Jessica."

"So, there's some girl here dressed up like me?" Jessica asked.

Dean struggled with how to answer that. That was obviously Becky, but in her mind, she was Jessica. He wanted to strangle her, but he guessed he would have to wait until he reversed the spell. In the meantime, should he tell her she wasn't who she thought she was?

SSS

Sam and the yellow-eyed demon were in the basement. Sam looked at the door.

"It's locked," the yellow-eyed demon said.

"What do you want?" Sam asked. Every encounter Sam had had with this demon had ended badly. His father had died, he had died, and that had led to Dean selling his soul.

"I want you to say yes."

"Yes to what?" Sam asked.

"To Lucifer. No need to play games with me."