Originally for one of the Percy-finds-out-he-has-a-twin-sister fics, but I'm posting it as a one-shot 'cos I've recently been in the mode to write one-shots of Percy finding out he has a sister in several different ways.


"Travis, take half of your cabin and go left. Connor, can you do the same, but go right?" The Stoll brothers nodded eagerly, setting about to get their cabin separated. Annabeth looked at her half-brother, Malcolm. "Can you organize our cabin?" He nodded. "Thanks." Annabeth smiled gratefully. Before addressing the next cabin, Annabeth scanned the demigods' faces, searching for Percy, despite knowing that if he were here, he would be at her side and not awaiting orders.

Annabeth pulled herself together. She had five minutes to quickly organise the last set of twelve cabins that were participating. Now that there were so many cabins and demigods, only twelve cabins could play at once, split into two teams.

But today, they were up against the Hunters of Artemis. Annabeth had been ecstatic to see Thalia again, but her mood had been dampened at the few previous games. Even if they went into one game and quickly into another, the Hunters energy was quickly restored. The campers hadn't won. Yet.

Annabeth was determined for the twelve Olympian cabins to win. She hadn't played against the Hunters before. The others had and had told her how difficult it was, but Annabeth's determination only grew stronger.

"Can anyone see Percy?" The match was about to begin, but Percy hadn't returned with the new camper, Louisa, who had wandered off. Chiron had insisted on her participation in the capture-the-flag match.

"He's on his way!" Leo replied, sitting on a low branch of a nearby tree.

"Thanks Leo. Ah… could you get down?"

"Why?"

"I'm not sure the nymph is too happy with a flammable boy in her branches."

"Uh…oh, ok." Leo jumped down. The nymph materialized briefly and kicked Leo in the shin, with a smug smirk on her face. A few laughed as Leo hopped about, massaging his new injury. He muttered something and a pinecone hit him in the side of the head.

"Leo, chill." Piper appeared, in her armour. Leo was glaring at the tree. Piper sighed and hooked her arm through his. "You really need to sleep more, Leo." Piper dragged him away from the tree.

Annabeth felt a hand on her shoulder. Turning her head, she saw Percy smiling at her as he tried to catch his breath. Behind him stood Louisa, who was looking at the other demigods, who were all wearing their armour. Annabeth noticed Louisa's lack of protection gear.

"Percy, you OK?" He nodded, grinning.

"She's… hard to find…" He breathed.

"Which explains why you're out of breath." He nodded in agreement. "Where's her armour?" Percy looked Louisa up and down before scowling. "Oh, Seaweed Brain! How could you forget?! The Hunters will kill her!" Percy smiled sheepishly.

"I'm missin' somethin'. What's goin' on?" A few of the Ares kids snickered. Louisa sent an evil glare in their general direction.

Leo's half-sister, Nyssa, took pity on her and explained the rules of capture-the-flag. Louisa understood. "Has anyone got any spare armour?"

"I got a helmet!" Travis replied. He passed it forward. Louisa took it, giving the plume an approving look.

"I take it you like red?" Percy asked her.

"It's an awesome colour." Louisa said, balancing the helmet on her fist.

"You're going to need that." Annabeth told her.

"Not really." Louisa said simply. "Thick skull, small brain." Louisa explained, rapping her knuckles on her head. Percy, Annabeth and most of the others snickered.

Louisa grinned at them before securing the helmet. Body armour was passed forward from someone in the Demeter cabin, who wasn't feeling too well.

Louisa was armed with her watch, but they didn't know that.

"Want a shield? Sword? Something?" Annabeth asked.

"No, I'm good thanks." The conch horn sounded and the cabins split up. "What am I doin'?"

"Whatever you want." Annabeth replied, remembering Chiron's orders. They still hadn't determined Louisa's godly parent.

"Cool." And she was gone.


Louisa was running through the forest, without an aim. Her instincts picked up on an approaching enemy before her hearing did.

She had just concealed herself in a tree when two Hunters burst into a clearing. One was Thalia- Annabeth's friend from earlier. The other was of similar height to Thalia, with thick auburn hair and sky blue eyes. Both were armed with silver bows and arrows, yet Thalia had a sword in her belt.

Louisa debated picking a fight with these two, but a shout caught her attention. She looked right as five children of Ares, including Clarisse, charged the two Hunters from the opposite side of the clearing.

Thalia drew her sword and met them head on, her weapon clashing with Clarisse's. Thalia's friend skirted the edges of the clearing, firing arrow after arrow. Louisa almost gagged on the strong stench of fart arrows. Too many caused a horrible smell that Hunters weren't fazed by.

Louisa recognized the next arrow as the Hunter stopped beneath her. A net arrow that, if fired correctly, could trap the demigods and leave them struggling for hours at a time.

Louisa whistled and the Hunter looked up, the arrow still ready to fire. Louisa dropped down as the Hunter darted away, aiming the net arrow at this new opponent.

"Where'd she come from?" Thalia shouted, ducking a slash from Clarisse's half-sister.

"She was in the trees!"

"Shoot her down, Karla!" Karla took aim and shot. Louisa summoned her sword and slashed at the arrow, sending the two silver halves tumbling to the ground. Karla stared at her, wide-eyed with awe and what Louisa hoped to be a bit of fear.

Louisa grinned wickedly.

"Thalia!" Thalia slammed her shield into Clarisse before risking a peek. Seeing Louisa free and armed, Thalia threw her shield (like Captain America). Louisa had a split second decision- duck or be hit.

Obviously, she ducked, the shield slamming into the tree that Louisa had used as cover. Louisa picked it up quickly, raising it in time as Karla bought a short sword down on her head. Louisa tripped Karla up with a Judo sweep and while the Hunter was down, Louisa disarmed her, taking the arrows for her own.

She threw the shield back at Thalia, who managed to dodge it.

She grinned cheekily at the five Ares kids before sprinting off.

Louisa's sword shimmered and became her red and gold watch. She managed to load her bow with a Hunter's arrow and fired up at a medium high branch. It was a net arrow. Two Hunters fell from their hiding spot, encased in the net, which had tied itself to the tree. The net spun one way and then the other, suspended two feet from the ground. They shouted insults after Louisa, who had already moved on.

Five minutes later, when Louisa reached another clearing, she had set eight traps- trip wires, that triggered nets or ropes to lift the one who had tripped the wire stuck until someone cut them down, or hanging upside down by their ankles. Other trip wires dropped godly strength stink bombs on the tripee's head.


Percy and Annabeth were fighting together, the Hunters silver flag (with the full moon and a silver bow and arrow on) five metres from their current position.

There was no way they could get the flag. The Hunters had rigged various traps and had various arrows, all with special, different abilities, fired in Percy and Annabeth's direction.

If it hadn't been for Louisa, who cleared a three foot bush and shot three arrows (at once) in the same moment, Percy and Annabeth wouldn't have got the flag.

Two of the arrows were 'flash-bang' arrows that blinded them momentarily. The third was another net arrow, which trapped the two Hunters who had been guarding their flag.

"Where'd you come from?"

"The forest." Percy ran to get the flag. Annabeth knew Louisa's random timing had been what they had needed- an element of surprise.

Percy returned.

You take the flag. We'll stop anyone trying to get it back."

"Why've I gotta take it? Why don't Annabeth take it? She did all the plannin'." Annabeth was grateful to be recognised for her work.

"Guys, we don't have time to argue. Louisa, you take it. You're the fastest."

"But-"

"Just take it!" Percy shoved the flag into her hands. "Now, go! We'll cover you."

The boundary line- the creek- was in sight. Running towards it, on the opposite side was Thalia, with the Athena flag. Annabeth scowled. Thalia noticed and shot her a cheeky grin.

Louisa put on a burst of speed.

Then the impossible happened.

She and Thalia jumped the creek at the same time.

It was a tie.

The conch horn sounded, signalling the end of the game. Louisa and Thalia still held the flags, staring at each other in disbelief.

Chiron appeared a minute later, along with a few demigods. It didn't take long for the Hunters and the Campers to file in.

"Do we have a tie?" Chiron asked, almost smiling.

"Yeah." Louisa and Thalia replied truthfully. Louisa flashed a devilish grin.

"Now what?" Percy asked.

"I believe a fight between Thalia and Louisa is required." Chiron said. There was a new light in his friendly brown eyes- one of hope. The Hunters had won consistently, almost a hundred times in a row. Now there was a chance they could break that winning streak. "Hand the flags over and stand five metres apart, one either side of the creek." Chiron instructed.

Thalia and Louisa obeyed. Chiron stood on Louisa's side of the creek. He caught her eye and gave an encouraging smile.

"That's a bit unfair." Annabeth quietly told Percy.

"What is?" Annabeth rolled her eyes. He scowled at her, but was smiling sweetly a second later. "What's unfair, Wise-girl?"

"Louisa's got to fight Thalia. The whole camp is putting a lot of pressure on her to win."

"She doesn't look under pressure." Percy pointed out. Annabeth looked at Louisa, noticing that the undetermined demigod's emerald eyes had a slight glimmer of unease.

"She could be trying to cover it up." Percy didn't answer, silently agreeing with his girlfriend.

"Fight!" Chiron ordered.

Thalia pounced, with her sword in hand, on the unarmed Louisa. Louisa ducked to the left, Thalia's sword grazing her shoulder.

Louisa did the natural thing and punched Thalia in the stomach. Thalia staggered back, winded.

Thalia regained her balance and stood up straight, her blue eyes flashing with power. Louisa stared her out.

Thalia's shield unfolded on her arm. Normally the sight of Aegis unsettled people, but Louisa's expression remained blank. What was she doing?

"Are you gonna fight or not?" Thalia asked impatiently.

"Mmm…" Louisa hummed, her tone monotonous.

Thalia's impatience got the better of her. She ran forward, her sword raised.

Louisa's sword appeared in her hand as Thalia's sword narrowly missed her throat.

The two exchanged jabs and blocks, parries and slashes. Thalia smashed into Louisa with her shield. Louisa fell heavily, losing her blade. She cursed in Latin and rolled away as Thalia stabbed down.


Louisa took a turning point five minutes into the fight. Her expression suddenly hardened towards Thalia.

Thalia charged Louisa for a third time.

In a matter of seconds, Louisa had grabbed Thalia's wrist, somehow made Thalia drop her sword. Louisa twisted and flipped Thalia over her shoulder.

Thalia pushed herself up, her back throbbing in pain. She glared up at Louisa, who stood her ground a metre and a half away.

The Hunter scrambled to her feet. Louisa's sword had disappeared and Thalia's own blade was too near Louisa to risk retrieval.

If Louisa was going to fight with hand-to-hand combat, then it was only fair for Thalia to do the same.

Thalia didn't charge Louisa this time. Instead she started walking sideways, in a circle. Louisa copied, keeping twenty paces from her opponent.

Louisa had a sudden burst of inspiration and sprinted towards Thalia unexpectedly. Thalia met her head on, bracing herself to struggle against Louisa.

But Louisa had other ideas. She dropped to her knees, allowing Thalia to miss and stumble forward. When Thalia's arm swung back, Louisa grabbed her wrist and stood up, staying in a slight crouch. She flipped Thalia over her shoulder again. Thalia groaned as she landed on her front on the hard ground. Louisa hauled her to her feet and had the Hunter in a headlock a second later. Thalia fought to break free, trying in vain to use her remaining strength. Her left arm was a disadvantage and Louisa knew it.

Thalia hooked her leg behind Louisa's and kicked forward. They both toppled backwards, Thalia gaining a few precious seconds to escape.

Louisa managed to free her bow and three fart arrows. She ran and jumped, firing down at Thalia. The fart arrows exploded in front of Thalia, disorientating her.

Thalia choked on the fart gas. Something collided with her, knocking her to the ground. The air was knocked from her lungs.

Thalia looked up and saw Louisa glaring down at her, holding her knife to Thalia's throat. Louisa was pinning Thalia down underneath her.

Louisa's glare vanished as she grinned with triumph. She got up, holding out her hand. Thalia blinked blankly at her before smiling and taking Louisa's hand. Louisa pulled Thalia to her feet.

"So did Lou win, or did they both win? I'm confused." Percy admitted to Annabeth. She laughed softly, catching Chiron's eye. Percy looked up at their teacher. "Chiron, who won?"

"Louisa did." Thalia announced, surprising everyone. It wasn't like her to admit defeat. "Fair and square." Louisa looked astounded. "You're a good and fair fighter and I respect you for that." Thalia laughed at everyone's shocked expressions.

Louisa gave her a cocky grin, holding out her hand.

"'N' I respect ya for bein' a challenge." They shook hands, grinning at each other.

Suddenly a sea green light momentarily blinded them all. When that faded, they all saw what had caused it.

A hologram floated about Louisa's head.

"Dude, I've got a ninja for a sister!" Percy grinned. Laughter followed before demigods, Hunters and Chiron bowed to Louisa. Percy bounded forward, standing at his new sister's side.

Oddly enough, a sense of relief washed over Annabeth. While Louisa had been undetermined, she had worried a lot as Percy and Louisa had got on great. Annabeth had been jealous. Now she could relax and keep Percy for her own.


This might be a bit :/ but I did type this, like, forever ago!