Percy opened a door with four Chinese figures on it.

Inside he saw a forest, with a clearing a little further ahead.

"Sokka! Get out of the bison's mouth!" A teenaged boy said.

Percy closed the door. "Okay. Was that just..."

He decided to try another.

"I carried a watermelon."

"What the Hades?" He decided to try one more.

"May the force be with you."

"Percy!" Clarrisse yelled before he could process this. "Get over here."

Percy flashed to his lieutenant who was standing next to a door covered in flowing script.

"You gotta see this."

She opened the door, flames licking at the cracks. From within a deep voice spoke. "My armor is like tenfold shields, my claws spears, the shock of my tail a thunderbolt, my wings a hurricane, and my breath, death."

Clarrisse closed the door, glaring at Percy. "Other doors lead to other places. We almost got shot by a nazi earlier."

"What's with the Smaug impersonation?" Jackie asked, coming over. "It was excellent."

Clarrisse opened the door again, revealing the huge dragon.

"Oh dear." Jackie said.

"I think I just saw the Avatar over there." Percy added, jerking his thumb at his door. "And possibly Star Wars."

"We're in the fandom side of Tumblr! I knew it was real!"

Clarrise smacked him with her shield, making Jackie the first demigod victim of such action.

"No." Leia said, "I think we are between the raindrops."

"What do you mean?" Chris asked the daughter of Athena.

"Multiverse theory. Each world is a raindrop, connected by the air. I think we are in the air in the metaphor."

"An astute observation." A deep voice said.

Guardians, Hunter, Death and God suddenly found themselves standing in a half circle around a man made of stars, only visible when he stood in front of door, or looked at you with his golden burning eyes.

"You figured it out much faster then I had even hoped. Well done, Leia of the Guardians. Greatings, Perseus, god of blue food, heroes, tides, times, guinea pigs, cheeseburgers, unfortunate explosions, pegasi and leader of the guardians."

He thought for a moment. "What am I forgetting. Oh, wait. ADHD and Sass."

"Your the god of Guinea pigs?" Clarrisse asked with an unimpressed look.

"You're the god of cheeseburgers?" Leo asked much more enthusiastically.

"You're Chaos, aren't you?" Percy said, trying to change the subject. "Why are we here? Why did you send Loki against your descendants?"

"That's simple." Chaos said, sounding unbearably pleased but no one was sure as he didn't have a face. "I needed help."

"God, capital G, needed help?" Percy said.

Chaos nodded, or at least, Percy thought he nodded. "Yes. You see, there is a saying that there is no such thing as fiction, only history written in the wrong universe."

"Are we a book?" Jessie asked.

"Yes, but-

"Do I have Fangirls?" Leo asked.

"Yes, but-"

"Awesome! I love you all!" He said, waving at the air.

"Bet I have more than you!" Percy challenged.

"Bet you don't!"

"Stay on topic!" Chaos straightened his camouflaged shirt as the guardians settled down. "Now, where was I?"

"You were telling us who has more fangirls." Leo said seriously.

"You were telling us why we are here." Clarrisse said with a glare.

"Ah, yes. Well, I need your help because some of these world didn't go quite according to plan. Sure, most of them ended well, but important people made the wrong choices or died before a perfect world came about. I want you, Perseus, you and your guardians to travel to each world and help it along, be it a small nudge, healing in a much needed moment, or, after you have been at it for a bit, war relief. You proved you could mesh well when you accepted Natasha Romanov to your guard."

All eyes turned to the former mortal. "Nat isn't from our world."

Chaos shook his head, again, only a guess. "No. She is from Earth-616, while all of you are from Eath 58,043. But no need to memorize those numbers."

"Then how did we meet?" Clarrisse asked.

"I took each world and meshed them together to see how you would adapt, using the Mist to keep you from realizing it. The first time I tried I had to start over because someone realized the discrepancies. When they caught on, I was forced to remove her from the equation and change everyone's memories. I apologize. I will return her now."

He snapped his fingers and mist, lowercase m, flowed from a doorway, taking the shape of a twenty year old woman. First to form was tattered jeans, next, the green guardian, cloak, finally, curly blonde hair and tanned skin. She opened her eyes, a startling stormy grey.

"Annabeth." Percy said softly.

He then promptly punched Chaos aka God, capital G, in the face.

"I deserved that." Chaos said as Annabeth Judo flipped Percy.

"You seaweed brain! Seriously! You couldn't think your way out of a paper bag!"

It took a bit but the pair finally stopped yelling at each other long enough to hear Chaos's explanation.

"Still pissed, but I'd rather have you back." Percy said.

"I love you too, seaweed brain."

"I'm so sorry I forgot again."

"It wasn't your fault."

Both leveled a glare at Chaos who smiled sheepishly, teeth a stary white.

Clarrisse decided to take up interrogation as both captain and lieutenant were occupied, it was the duty of the third in command.

"So you want us to run around helping people in other worlds?"

"Yes, to nudge it on gently in a way that no one will realize that you aren't natives. Be it you pretend to be aliens, fae, elves, daimons, spirit, or angels."

"And, since we don't know which door is ours we can't go home until we are done." Annabeth added, holding hands with Percy.

Chaos grinned. "Exactly."

"How many worlds do we have to help before you send us home, I demand a contract stating the terms of our deal." Annabeth said. "Along with compensation for kidnapping, faking my death, and illegal alteration of memories, along with holding us all against our will and forcing us into servitude." She leveled a rather terrifying looked at him, equal parts, expectant, intimidating and disappointed.

"Uhh..." Chaos began, taking a nervous step back. "Increased abilities?"

Her eyes narrowed.

"Along with invisibility cloaks."

She started to tap her foot impatiently.

"Along Shapeshifting abilities based on godly parent, personality and past?"

She took a step forward.

"And a way to communicate with your friends and family."

Her hand rested on her dagger.

"Tent of Requirment!"

Annabeth smiled. "Pleasure doing buisness."

"She scares me." Leo told Percy.

"Me too." Percy replied.

"Anything to add, Percy?"

"No, ma'am." Percy paused. "Uh, no, you did great." He turned to Chaos. "Where to first?"

"First up is Camelot. You can take certain people who are not imperative to the timeline with you, but but I'm afraid that this does not apply to one of your number. You will have to leave them behind."

"Me." Nat said, pushing her way forward. "I have to stay."

Chaos nodded. "Your destiny lies with the Avengers. But worry not, I shall reverse the time stream to right before Fury learned of Perseus. I'm also going to remove your memories."

"Seal." Percy said. "I understand why she can't remember but I'm placing a claim."

Chaos looked impressed. "Very well then."

"Claim?"

"Something only Artemis and myself can do. I'm placing a claim on your soul. My very first one. When you die, you shall have the option of moving on to the afterlife or returning to the guardians in the same form you were in when the claim was placed. I will also seal your memories until after your death or you need them in order to save yourself from circumstances out of your control."

Natasha nodded. "I'm okay with that." She leaned forward and hugged him. "Thank you." She looked around. "All of you. I may not remember but I will definitely miss you."

"We'll miss you too, rookie." Clarrisse said. "Good luck."

"Goodbye, my fellow firebender." Leo cried, his hair on fire.

"Thanks for giving the widow stings to the hunters." Thalia said.

"We will definitely start teaching jiu-jitsu." Alena said.

"You taught us so much!" Travis and Conner sobbed as Nat laughed.

"I'll miss every single one of you. I swear on the River Styx."

Thunder rumbled and everyone began to step back.

"Alright." Nat said. "I'm ready."

Percy held out his hand and gave her a hug, Percy's crest appearing on her back, a crossed sword and trident, before fading away.

He stepped back and smiled. "May your sword stay sharp, the gods pleased."

"And the monsters with runny noses." The others chorused.

Nat's eyes went dim and she vanished into the mist.

Percy turned to Chaos to find he had vanished.

A doro stood before them, crimsion red with a dragon emblazoned on it.

Words encorcled the beast.

In a land of myth, in a time of magic, the destiny of a great kingdom rests on the shoulders of a young man.

His name: Merlin.

Smiling sadly, Percy opened the door.

-----------

Okay, so I just made myself cry. I love Nat so much that I almost had her come with them but, as they say in Albion, a life for a life.

I'm planning a number of small crossovers, some brief, some a few chapters long. I'm not sure if I will continue to post to this story or start a new one. I'm thinking the second.

I fell in love with my guardians and the havoc they cause in crossovers so first stop, Camelot.

See you there.