Hey guys, this is my first time ever doing a Percy Jackson/ Harry Potter one. I started thinking about doing this fanfiction when I finished The Mark Of The Athena Book. I got really excited to see what happened to them in the House Of Hades. Unfortunately, it didn't come out, yet. So...this will calm me down from my obsession of Percy Jackson books.

EnJoy!

I do not own Percy Jackson nor Harry Potter.

Dark...beneath the Earth is her...The Earth goddess, Gaea. Asleep she is. She was still asleep when around her, a dark, shadow cloud formed. She felt this dark magic swarming her. The dark cloud formed into this creature she has never seen in her life. She thought it was some giant that she felt. She couldn't see it, she could only hear it whispering, some sort of spell. It stopped whispering and everything filled her with it. Finally, at long last. She can stand, able to walk again. She was...revived. She didn't need to spill the blood from the demigods no more...She was free.

She looked up to his face. He was bald, no nose, bare-footed, and held a wand. "Lord...Voldemort, I am glad to see you again. After that betrayal, I thought you would never ever come here. Why did you revived me?"

"I need your help...There's a boy who I can't get rid of."

Gaea laughed."Yeah, I'm not going to be a part of this silly game..."

"Oh...but, it involves that boy..son of Poseidon."

She had a grin on her face."Oh really? Does it involve with the other demigods?"

"Hopefully, it will. We both know that we want to rule the world."

"Hm...it sounds interesting. Who's the boy that you can't get rid of? Powerful? A demigod?"

"A wizard. Yes, powerful. Powerful, same as that son of Poseidon."

"I'll join in. What's the plan?" Both of them started to get blurry when...

"Wake up, Wake up! Wake up, Harry!"the voice said.

Harry shivered, grabbing his glasses. They were still at Hogwarts."Ron?"

"Sorry, but you were sweating like buckets and shivering...Is it a bad dream again?"

He nodded."Yes, but it's a dream that never happened to me."

"Alright, I'll go down the Great Hall. We can talk about it with Hermione."

"Alright, see you there."

"WHAT!?That's insane!"Hermione slammed her hand down the table. Everyone was staring at her.

"Voldemort...um...I meant 'You Know Who Is Back'? Didn't we...um..you know killed him?"Ron said.

"I don't know. It is a dream, but I got confused when I heard about a son of Poseidon and some demigods..."Harry said, rubbing his forehead.

"And that a lady in the core of the Earth is revived?! That's crazy! How can someone live in that heat?"

"I don't know...but whoever this son of Poseidon kid is...he's in trouble and we need to help him."

"You know what, let's go to the library today. I think you are talking about Greek mythology. Surely, we will found about a son of Poseidon. Wait, if Poseidon has a son, who is his mother and the son's name?"

"A Greek mythology class should be great for her,huh?"Ron whispered to Harry. Harry nodded, looking at Hermione still thinking about the Greek mythology.

He sighed. He's finally at Camp Half-Blood. He missed this place sooooo much. He can be with Annabeth, Hazel, Frank, Leo, Piper, Jason.(Sorry, I kinda left out Nico out. I didn't want too much people in my story that much.) As he entered, many people greeted him and welcomed him back. He was really tired from the battle with that giant and rescuing Annabeth from almost falling into the pit with that big spider.(Sorry, but I kinda , made some of it up, because I really don't know what happened to them. So I didn't know how to put it that way, but don't hate me because of that.) All he wanted to do was relax in the lake. He was glad that Reyna accepted Hazel and Frank could come to Camp Half-Blood. It's not like it's a better place than Camp Jupiter.

"Seaweed Brain, where are you going?"Annabeth asked.

He just realized that he dozed off ago and almost went to the girl's bathroom way."Oh..um I'm going to relax at the lake. I'll see you soon."

"Um..that's the girl's bathroom way.."

Hey moved to the lake's direction."How about now?"

"Alright! I'll see you then"Annabeth went up to him and kissed him in the cheeks and went with the others to their cabins.

"Wait, Percy!"Hazel and Frank yelled. They didn't have a place to stay yet.

"Oh, what's up?"

"What's up? We don't have cabins, Percy,"Frank said.

"Oh, yeah. Sorry about that. I just wanted to rest for a little while. I'll tell Chiron about it..."

"Nah, you don't have to tell me about it. Reyna already messaged me."Chiron said." Anyways, I'll show you where your cabins should be, follow me."

"Awesome! See you later, Percy!"Hazel shouts, following Chiron.

"I'll see you later. Have fun relaxing!"Frank shouts, catching up to them.

Percy continued to walk to the lake. He dropped his bags, took his shirt off, and stepped into the water. It felt refreshing. All the injuries on him healed away, leaving him underwater, seeing little sea creature swimming around him. He closed his eyes, taking a nap. But then, he heard whisperings.

"I'm back Percy Jackson, prepare for your worst nightmare..."

It faded away."I'm sure I heard Gaea's voice, but...wasn't she dead or still asleep? She did needed Annabeth's and my blood to spill, so she could revive,"he thought in his mind.

"Don't worry. I don't need that to revive me...I already have someone who can.."

He could hear her laughing. He quickly got on land, put his shirt on, grabbed his bags, and went searching for Annabeth and the others.

Harry, Hermione, and Ron went up to the library. A lot of people were crowded in there. They all went seprarate searching through the sections.

"Greek mythology, Greek mythology, Poseidon, Poseidon, POSEIDON!"Hermione yelled, getting the book out from the shelf."Harry! Ron! I found the book!"

"Why does she always find everything first?"complained Ron.

They all sat down on the table. She started on the first page, looking at the picture.

"That's Poseidon, wow...he's humongous.."

"Shut up, Ron! Just let me read!"Hermione snapped."Anyways...Poseidon is the Greek god of destruction, earthquakes, horses, hurricanes, oceans, seas, storms, and other water bodies. His brothers were Zeus and Hades."

"Who are..."Harry quickly shutted his mouth.

"Well, he has 3 daughters named Demeter, Hera, and Hestia.?What!? This is a blank page. Your dream says that there was a son of Poseidon!"

"Maybe, some one ripped it.."Ron explained.

"Maybe..."Hermione sighs. She started sniffling.

"Hermione, don't cry. It's just a book."

"No...I'm not crying."She sniffed more."Do you guys smell that?" They started sniffing. It smelled."RON! Did you just..."

"Farted?!"Harry says, holding his nose.

"Of course not! Not in a million years will I stink like this!"

Everyone started running out the doors. As well as Harry, Hermione, and Ron. There was now green smoke in the library.

"You wizards are so stupid. I'm the one who ripped the page out,"says a woman behind the book shelves. She had a grin on her face.

They were at the common room, now, catching their breath.

"Oh my gosh, that was a nightmare, right Hermione?"Ron says. She was scanning the table."Hermione?"

"THE BOOK...where is it?!"

"Hermione, chill out. Don't worry, as soon as the.."He started snickering."the..the gas clears up...We'll go back."

"Ron, this isn't funny!"

They heard the door slammed very hard. They stared at the person who came in. Only Hermione stood up.

"Excuse me, who are you? Why are you doing in our cabin? How did you come here? Slytherin..."Hermione says.

The person grinned, flipping her hair."I am Gaea. I just joined Hogwarts and I just typically got lost."

"Got lost?"She remembered about the sorting hat,but didn't remember a name, Gaea in there. "If you've gotten lost, how can you know the password?"

"Guessing, sort of? Anyways, I saw you guys in the library and you left this,"She showed them the book that they left.

"Oh my gosh, thanks...I didn't expected you to be in that group. You look...very nice. Most of the Slytherins just take it and read what they had."

"Hm...I am very different from everyone"

" Anyways...Thank you for returning the book, I'll see you soon then!"

Harry looked at Gaea's face. It looked really familiar in his dream. Gaea left and they sat down, continuing reading the book.

"Oh gosh guys. I found where the son's page were, hah! Let's see now..."She ran through the book."Oh my...HARRY!"

"What?"

"Your name...it's on here! You're one of the sons of Poseidon?"

"No...no, it can't be. Voldemort would've already told me that...Read about what it says about children of Poseidon."

"Well, you can breathe underwater. And you did, remember the Goblet of Fire?"

"Neville gave me that thing,"Harry argued.

"Anyways, you can control water. Didn't you did that in the Chambers of Secrets?"She looked at his expression. She kept scanning through the book."And... other things, but I think these 2 are the most important."

"Hermione, I am dead serious. I am not the son of Poseidon! Do you think I am, Ron?"

"Well..."

"You know what, let me go ask Dumbledore then,"Harry got up and ran through the door.(Sorry, but I letted Dumbledore stay alive. I kinda needed him in this story.) He didn't realized that Gaea was at the corner of the doors.

"Hm..they now believe that the boy is the son of Poseidon? Well, the plan is going well, Voldemort. I ripped the page off and pasted a new one. How do you like it?" She went back to her cabin, grinning as possible. She could hear Voldemort laughing.

How do you like it? Tell me! But look forward to the next chapter! REVIEW