Annabeth took a sword from one of the fallen Demigods at her feet and performed a vertical slash at an enemy. The enemy jumped back, but was hit with an arrow that went through their skull killing them immediately. The daughter of Athena shivered at the sight. Annabeth then blocked a blow aimed for her head and she pierced the Demigod's heart, killing him immediately.

Annabeth dodged another blow and slashed at her attacker's hand, cutting the tendon before killing the demigod. Thoughts rushed through the daughter of Athena's mind as she ended more Demigods.

'I must do this,' she thought to herself, cutting down monsters and demigods that attacked her. 'This is for the best. It's either them or us. The few or the many.'

Annabeth is not enjoying the culling of so many Demigods. But she knew that it was necessary. Unknown to her, she was starting to become stoic as her eyes slowly gained green streaks. As the battle raged on around Wisdom's Daughter, her skills increased. Her form, graceful. The way she stood showed a true leader, a true King. 

Hours went by as Annabeth fought more and more. Her shirt was soaked with sweat and blood. But she still went on. Only one goal in her mind, protect the innocent.

With Percy

Percy Jackson was living up to his title as he sniped at monsters and Demigods alike from his perch on the Empire State Building. How can he see the individual monsters from that height? By using reinforcement on his eyes he can see far better than a son of Apollo or a Hunter of Artemis. He stopped sniping for a moment when he heard a voice in his ear thanks to a spell seal there that Piper placed on him and the other Cabin Leaders, plus Thalia.

"How is everything looking up there, Perce?" Thalia asked him.

Percy smirked and replied with, "Everything is alright, but," Percy reinforced his eyes and looked down a little ways behind him. "The Hermes Cabin are dealing with a few telkines and a couple of Cyclops as well."

"And they didn't invite us?" Thalia asked rhetorically.

Percy chuckled, before turning his head in a different direction and his eyes widened.

'What is this mana?' the son of Poseidon thought. 'It feels... Familiar, but at the same time, it doesn't. Is this Saber?'

Reinforcing his eyes even more, Percy saw Annabeth fighting, watched for several minutes, before he aimed an arrow at a monster behind her and let it loose, the arrow entered the monster's head and through the eyeball before it turned to dust.

Annabeth just barely turned her head to look behind her and she saw dust fall before giving a nod and began fighting anew. Percy then looked in Thalia's direction and muttered a curse in Japanese.

"Thalia," he notched an arrow on his bow and pulled on the string, "when I say move, you move. Understand me?"

"What do you mean?" he heard Thalia ask through the spell seal on his ear. "Why must I..."

"Just do it!" roared Percy his eyes talking on a dull silver sheen. As the Archer drew back on his bow, he said, "This body is made of Swords." A burst of mana erupted from him and he released the bow shouting, "Move Thalia! Now!"

Percy watched as his arrow went through a monster and the werewolf known as Lycaon. Killing both of them at once.

"You're welcome Thalia," Percy said into the spell seal before jumping off the Empire State Building and landing on the ground safely due to Reinforcement. Percy then shot forwards like a cannonball shot out of a cannon. Summoning his blades, Kanshou and Bakuya, he began to send monsters to Tartarus. Soon, after a few hours, he found himself with Piper.

"Got tired of sniping, Archer?" Piper asked, while healing an ally Demigod.

"Something like that," Percy replied, he then threw Kanshou and Bakuya and the two blades cut through two cyclops before the swords acted like a boomerang and returned to Percy hands. "This is taking too long. We need to get this war over with before the casualties become too great."

"But how?" Piper asked, once she was finished healing the Demigod.

"I know how Luke is able to host Kronos," Percy told Piper. "I had to do the same thing in order to stand a chance against him. But it is also what made my memories and powers return."

"What did you do, Jackson?" Piper asked threateningly.

"I took a swim on the River Styx," Percy whispered before he ran into the battlefield and summoned the married swords once more.

Piper's eyes widened as she realized what the Archer did and how much danger he was in.

"Sono baka!" Piper shouted in Japanese. "We will be having a talk about this Perseus Jackson!"

Percy sighed as he killed a hellhound that attacked a 'hole' in his guard.

"How stupid can these people get?" Percy asked, killing an enemy demigod. "They always attack the holes in my guard, which is a good thing considering my quick reflexes."

Thanks to his memories as Emiya Shirou aka Archer, being integrated into this life, he also gained, not just his memories and powers, but also Archer's battle style. By leaving holes in his guard, and knowing that his opponents would always go for the holes to get him out of the fight quicker, he'd be able to know where they will attack. And due to his class skills, he's able to read his opponents better than most, thus making this combat style even more deadly.

(A/N: Hope I did a good job explaining it. I got this explanation by reading some Fate/Stay Night crossover fanfics. So I am not sure if I did it right and as such, I am most likely wrong on it.)

As the battle began to reach it's climax, Percy felt another burst of mana. One that was far greater than before and one that came from Annabeth's area of the battlefield.

"Annabeth," Percy muttered. "I need to get up high."

Reinforcing his legs, Percy jumped atop a building and then reinforced his eyes which then widened the moment he laid eyes upon Annabeth.

With Annabeth just moments prior

"Hello, daughter of Athena. Where is the son of Poseidon?"

"Hyperion," Annabeth stated, her face emotionless except for a slight flicker of fear in her eyes. "I should've known that you'd be here."

"Yes well, Lord Kronos wanted to have me so that you all would perish at my strength," Hyperion gave an evil grin here. "He wants you all to suffer for the disruption you have caused in the past few years."

"On my honor, you will not succeed," Annabeth declared, slashing the air with the stolen sword. "I'll die before I let you go against Percy and anyone else."

"'On your honor?'" Hyperion questioned, before letting out a bellowing laugh. "What are you? A knight?"

For a split second, Hyperion felt as if he was in the presence of a king. One that would slay even the mightiest of monsters or even gods to protect their home.

"Yes," Annabeth replied as a powerful burst of mana erupted from her. "I am a knight."

https://youtu.be/HVPZ-KZNlrQ

(Please play the song above to truly appreciate this last bit of the chapter. Thank you.)

With those words, time seemed to freeze around her and a lady with hair as dark as a raven's and eyes as blue as the deepest of oceans appeared in front of her. The woman was wearing an old styled dress that was a sky blue color. Her skin was the color of freshly fallen snow.

"Lady Nimuë," Annabeth muttered, as the name came to the forefront of her mind. "Wait... H-How..."

"How do you know who I am?" Nimuë asked with a small smile. "You know because I gave you your sword, Queen Artoria Pendragon."

"Then these memories," Annabeth began, holding her head in her hand. "These sword skills that I gained throughout this battle... That is my past life? I was the female version of King Arthur?"

"Otherwise known as Saber," Nimuë replied before a sword appeared in a flash of light. "Are you going to pick up your sword again, my Queen?"

Memories flashed through Annabeth's mind as she remembered Kiritsugu and Irisviel and then becoming Shirou's servant and falling in love with her Master. All before Archer's betrayal and fight with Shirou.

"Yes," Annabeth replied, her hands reaching for Excalibur and it's sheath Avalon. "Thank you Lady Nimuë."

"Your welcome, my Queen," Nimuë replied before vanishing and disappearing from in front of Annabeth as time went back to normal.

In another burst of mana, Annabeth's Grecian armor and modern day clothes disappeared and changed into shining armor with an old styled dress, made from old-fashioned blue cloth, underneath. Her hair was also now in a bun and two bangs hung over her face. Her eyes, while a startling grey, now had flecks of dark green.

"Who are you?" Hyperion asked in shock at the sight that lay before him.

"Who am I?" Annabeth asked her hand going to the sheathed European styled blade at her side. "I am Annabeth Chase! The King of Knights!" She then drew her sword and a burst of air erupted from behind the demigoddess as she charged forwards.