I want you to give you guys a heads up, there will be a Percy Effect. This basically means that Percy being in this story will change events that happen. Percy does change the story in small ways at the start, but as the story continues he will effect major events...

Also I know there was a complaint about rushing, but I couldn't find a way to fit Percy into the first two seasons. And no Percy will not just be rotting in a cell for like 10 chapters, but the ones he is in the cells you are going to get flashbacks of his time with some of his family members. Just wanted to point out again that the story will primarily be seen through Percy's view.

"Come on Robb! Are you even trying!" Percy joked as he twirled his sword playfully in his hands. Robb rolled his eyes at his younger brother before rushing forwards and swinging his blade. Percy easily deflected his attack, before swinging his leg and knocking Robb off his feet. Robb hit the ground straight on his ass, and then his sword was kicked from his grasp, before Percy's sword was at his neck.

"I yield," Robb said annoyed resulting in his younger brothers smirk. Percy removed his sword from Robb's neck and then offered his hand instead. Robb took it and allowed himself to be helped up.

"You better hope if we're ever in a battle together that I'm there by your side," Percy stated bluntly, "Otherwise big brother you may end up dead!"

"I can beat everyone in this town but you!" Robb argued, "Well you and Jon."
"You beat Jon sometimes, he beats you sometimes," Percy said, "But at least Jon is a challenge for me!"

"Not all of us have been blessed by the gods brother."

"I disagree," Percy stated his hand reaching into his older brothers shoulder, "Were blessed to be part of this world, to be born into a noble family. A loving mother and father, along with all our lovely siblings!"

"You are right about that brother," Robb admitted looking at his younger brother with a small smile. Even though Percy had no Stark blood in him, nor shared much resemblance to their siblings. He had raven black hair, and piercing sea green eyes. He stood at least three inches over Robb, and had twice the muscle on his body as well, his skin seemed to be naturally tan, even in the gloomy cloudy weather of the North, compared to the rest of the Starks naturally paled skin color. None of that mattered Percy was his brother. Blessed by the gods to have power over the sea, and it was a wonder to see Perseus manipulate water, and he even claimed to be able to understand horses.

"I'm going to miss you Robb," Percy stated a saddened smile on his face.
"And I You brother."

They embraced in a long hug, both of them remembering fond memories of each other from their childhood.

"Don't do anything idiotic till I get back," Percy whispered into his brothers ear.
"Don't worry Perseus, luckily for the both of us you're the Idoit," Robb joked receiving a small chuckle from his brother.

ROUGHLY NINE MONTHS LATER

Robb Stark hacked angrily at a tree with his sword, he was letting all his emotions out... all the pain and suffering he felt in his heart. He had been so close to getting his family back, he had Jamie Lannister, he could have traded the King Slayer for his family's lives in return, but before he even had the chance the boy King Joffrey had hacked his fathers head off.

Now his brother Perseus, and his two sister Arya and Sansa were hostages to the thrown. There was still a possibility of him getting his family back with Jamie, but none of that mattered anymore to him. Everyday he did nothing meant his brother and sisters were in danger. He had an army, and if he had to he would march all the way to Kings Landing and murder anyone in his path to get them back.

"Robb?!" He heard his mother call out but he ignored her and continued to hack away angrily. His mother called out to him three more times before he turned towards her, revealing his tear stricken face.

"You've ruined your sword," She said lightly, only resulting in Robb letting the Sword fall out of his hands as he let all his emotions out in front of his mother.

"I'm going to kill all of them!" Robb roared tearfully.
His mother ran to embrace him, and he let her as he wept on his mothers shoulder and repeated, "I'm going to kill all of them!"

"They have your brother and sisters," His mother reminded him, "We must get them back first. Then... Then we will kill all of them."

A few months after Neds Death

Percy was suddenly awoken as the loud sound of his cell door opening. He sat up tiredly and rubbed his tired eyes before glancing towards his opening cell door. His eyes widened in shock and joy as he saw his younger sister, Sansa, standing there un harmed and in one of her beautiful dresses.

"Sansa! Thank the gods you're alright!" Percy exclaimed, "Is Arya here as well?!" Sansa shook her head no, filling Percy will fear and worry for his other sister. Sighing he motioned for her to come closer resulting in Sansa rushing forwards and embraced him, and he could hear her muffled cries. He let her cry, as he sat there unable to comfort her except for being able to shush her lightly with his lips, as his hands were cuffed and he was unable to even hug his sister back. After some time she pulled away and wiped her face, and did her best to smile at him, when he noticed a slight bruise on her cheek.

"Who did this to you!?" Percy asked angrily nodding towards it.
"Joffrey ordered the hound to do it," Sansa admitted sadly, "He showed me fathers head! Then said it would be joined by yours and Robb's!"

"Why Robb?" Percy asked curiously, after all he figured he would receive some sort of fate similar to his father after delivering an example of brute force of his powers.

"He's raised an army," Sansa said, "He's been proclaimed King in the North, and he has Jamie Lannister prisoner! Perseus he hasn't lost a battle, he could save us!"

"I told him not to be an Idoit," Percy groaned as he hit his head on his cell wall in frustration. Robb was marching the North down to Kings Landing, leaving Winterfell unmanned, and leaving his two younger brothers and mother defenseless. It would take months for Robb to March down un bothered, but to fight a war at their state would cause massive bloodshed and delay him so much further. He was now King, meaning Joffrey only had six realms now, and would want to take back the seventh. War would reign, destruction, lives lost, family's destroyed, villages, houses, good farmland would all be destroyed over a war over revenge. However, considering both of Roberts younger brothers Renley and Stannis had both proclaimed themselves the true kings, meant that Kings Landings army, which was mainly the Lannister's men, would have to fight a war on many fronts. After all Stannis was the master of ships, and had left with a large portion of the fleet, and who knew what support Renly could find himself with.

"Perseus I though you would be happy," Sansa said confused, "Robb is going to set us free."

"My sweet sister," Percy said smiling, "I just fear for Rickon and Bran... He's fighting a war for us, for father... but war is nothing glorious sister, I fear that Robb may be in over his head. He's going up against the King-"

"Robb is now a king as well," Sansa stated.

"I know, and you're still set to be the future queen, now let me finish. He's going up against the king, the son of Cersei Lannister, and if Robb has Jamie Lannister as well... then he his going to be fighting one of the richest men in the world, Tywin Lannister... and he has enough money to buy an army double the size of Robb's... hell maybe even triple," Percy explained. He felt saddened as Sansa, whose face had been so full of hope a few moments ago crumpled and she looked down at her hands sadly. Sighing Percy took her hands in his as best he could and said, "Sansa... Robb may very well March all the way to Kings Landing and save us, but do not count on it okay?"

"Okay," Sansa said with a sniffle clearly trying to stop herself from breaking down once again.

"I need you to be strong Sansa okay? Do what you're told, do what you must to show you're loyal to the crown even if you're not. We have to do what we must to make sure we survive, and when the time is right we will get justice do you understand?" Percy lightly said showing off his classic smirk to lighten the mood. Sansa nodded and Percy continued, "Now... any news on if I'm going to be killed like Joffrey wants?"

"The Queen... or I guess it's Queen regent now... has told me that you will be safe as long as Robb has Jamie."

"And you're safe because you're our future queen," Percy finished, " Well I'm so happy you have came
down and visited me Sansa, but you can't stay down here. This is no place for the future queen, you have to show your loyalty to the Lannister's right now even if it just pretend. They most likely won't let you back down here sweet sister... Be safe, I'll be out of here before you know it."

-So as you guys know. The prologue was basically just a summary of season one and how Percy was fit into it. For right now, Percy is going to be in the cell, and most interactions will be with Percy in his cell as the story is going to mainly revolve around him and not the other characters. Though there will be interactions with just the other characters to fill in story points, and there will be plenty of flashbacks as Percy has nothing to do but sit in the cell until he is out of it. Thanks for reading please leave a comment or anything it'll be appreciated.