Disclaimer: I don't own Percy Jackson and The Olympians, Naruto, or Ant-Man. This is all just for fun, so calm down.

I said CALM DOWN!

...Thank you.

Size Always Matters

"I'm the boss. I'm the boss. I'm the boss."

A lone figure was running across the rooftop towards the Queensboro Bridge. He was a young teen, barely grown into his still kind of lanky sixteen-year-old body, wearing a motocross suit made of dark leather and Celestial Bronze-plates, a crude number four painted on his back. His face had whisker-like marks on either of his cheeks, his hair was a mess of blond, and his eyes were a heterochromic mix of earthy green in the left and deep ocean blue in the right. He panted with each pump of his arms as he leapt to the next roof, stumbling before he pressed on. August had barely started and Manhattan was in shambles. Mortals were unconscious, monsters roamed the streets, and demigods were killing each other.

That last one might've thrown some of you, so here's a quick recap: The Gods of Olympus, the so-called 'myths' were actually real, so don't call them that. Their archenemies, The Titans, were also very real and currently engaging in war with the aforementioned gods. That war happened to be centered in Manhattan, because the Gods' home, an overlapping plane of existence called Olympus, which used to rest on the Greek mountain that had been named after it, currently resided there. The demigods, well, the Greeks were famous for them and they never quite stopped.

"I'm the boss!" The blond told himself as he jumped to another roof, stumbling only slightly. A sharp whistle made him look up to see descending rocks and boulders that were lit aflame. "Oh, come on!"

He scrambled to his feet before he threw himself to the next roof, ignoring the sounds of the rocks' impact behind him, his eyes locked on the Queensboro as he kept running. He had to get there yesterday. The only problem was the intersection coming up. A pair of giants spotted him and were attempting to prepare an ambush. Attempting because, well, he saw them coming and can hear them arguing about who gets to eat him first. Unfortunately, if he diverted now, he risked being picked off by something else or being squished by the artillery coming from Queens.

What felt like a tug at the base of his ear made him tear his mismatched eyes away from the upcoming intersection. Green and blue orbs lit up when he saw a small cloud of dots coming his way at a high speed. Hope swelled inside his chest. He turned his attention back to the intersection, bending forward to pick up more momentum. Just a few feet before the edge, he jumped up, balled his hands into fists and willed his body to compact.

In the blink of an eye, he shrank.

By the next, he landed on the back of a carpenter ant. Repositioning himself atop her back, the blond patted the ant on the head.

"All right! Thank you, Ant-Ena!" He grinned and settled on her back, diverting her and her kin to the bridge. "Now let's get to that bridge!"

The ant and her swarm listened. The teen braced himself. He saw the horde of monsters crossing the bridge, the slumbering mortals on the road battered and knocked around like they were nuisances. Cars plummeted over the edge or were crushed against barriers. The army of Kronos, King of the Titans, was nearing the middle of Queensboro.

His orders from the 'General' were sound and clear.

"Are you even listening to me, Naruto?"

The armored teenage girl glared at him with steel-colored eyes. Between them was a map of Manhattan and set to the corner of New Jersey was a laptop, currently in sleep mode depicting a bouncing ball that would not hit the corner of the screen. It would be driving his A.D.D. crazy if not for a little thing called hormones. Self-preservation gifted to him by his Greek ancestor, not of the combat variety, had him barely managing to focus on the girl.

Annabeth Chase was a babe with a big brain. That was an eternal truth, and anyone in Cabin Seven would back him on that. However, she was also head over heels for the Son of Poseidon, Percy Jackson, and had been for years, if his gal-pals in Cabin Ten were right. So, as diplomatically as he could, Naruto looked her in the eye and grinned.

"Of course I am, Annabeth!" he lied.

"Then what did I just tell you?"

...Crap baskets. Quick, think of something really clever!

"You need me on the frontlines to kick monster ass!" He punched his palm.

Ha! Nailed it.

She pressed a hand to her head and muttered under her breath before she pointed at the map.

"Almost. I need you to go reinforce my cabin at the Queensboro Bridge. The giants will probably come from there." She gave him a flat stare before crossing her arms. "Think you can manage that?"

"Is that all? Pfft, yeah, I can manage it." He grinned and pointed a thumb at himself. "I'll get that bridge up faster than you can say Nothomyrmecia macrops!"

"It's a suspension bridge, Naruto."

"...O-Oh." Naruto's grin faltered. "Well, uh...then I guess you'll need me to help set bombs or something, right?"

"Naruto."

"Grow weeds to block it?"

She arched a brow. He sighed.

"...You want me to Kaiju it."

"I want you to Kaiju it." She nodded. Naruto groaned. Suddenly he didn't feel so thrilled about being pulled aside by the camp's 'General'. He rubbed his neck.

"Okay...so...But what if I...what if I can't?"

"What do you mean?" Annabeth frowned. "You shrink all the time!"

"Yeah, shrinking is easy! It's almost second nature!" He did so in the blink of an eye, reverting back to his normal height just as fast. "But getting bigger? Not my strong suit."

"You did it during the CTF in '04!"

"That was an accident! I was still in Cabin Eleven then!"

He didn't even remember what had triggered it. He just remembered running through the woods, trying to keep pace with the others, and then losing sight of them. Something snapped his ankle when he chased after Conner, and then it was dark. He woke up in a daze, panicked wherever he was, and then he was towering over the trees and the campers all looked like frightened ants. He was claimed shortly after he managed to return to his normal size.

"Naruto, you have to." Annabeth urged, drawing him from his memories. She put a hand on his shoulder. "You're the only member of your cabin that got this ability from your godly parent. The only camper who can alter their size! We need that part of you. Olympus needs that part of you."

"Great, no pressure."

A jerk from his ride snapped Naruto out of his thoughts. Looking down, he saw that he was directly above the bridge, with Roosevelt Island directly below that.

"Showtime." Naruto patted the young queen on the head before he stood on her back. He took a deep breath, hesitated and then looked at the ant once more. "Ant-Ena, if I don't make it, name a thousand of your kids after me."

The ant's mandibles snapped and he understood the message she was relaying. Naruto nodded, swallowed some spit to wet his dry mouth. He closed his eyes, thought of the feeling that led him to being claimed, and looked down at himself. Lightning illuminated the sky from the fight between the gods and Typhon, the crudely painted number four on his chestplate. Naruto thought of his dad out in Louisiana, swearing to himself that if he made it out of this he would go back down and tell his dad that he loved him.

"I'm the boss." The whiskered teen psyched himself up. He clapped his hands on his face. "I'm the boss. I'm the boss. I'm the boss. I'm the boss."

Then, finally, Naruto jumped.

Adrenaline raced through his system as he descended. Mismatched eyes narrowed as they focused on the atrocities being committed by the small group of monsters crossing the bridge. He took hold of the anger, the fear, welled it up inside. Built on it. Embraced it.

Then, with absolute confidence in himself and his abilities, he cried out: "I'm the boss!"

The ground shook with his landing, the bridge collapsed beneath his feet, and for the second time in his life, Naruto Namikaze was a colossus given life. The group of giants that had been advancing on Malcolm and the rest of Cabin Six looked like G. I. Joes while the other assorted enemies appeared to be green army men. A portion of the platoon had stopped and stared incredulously at the three hundred-something foot tall demigod, but the giants continued to lumber on. Naruto reached down and grabbed the closest giant and hoisted it up.

"Where do you think you're going, Short Stuff?"

"...To kill Olympians?" The giant got points for its honesty, but lost a lot more for its stupidity.

"Wrong answer." Flipping the giant in his hand like he would a football, Naruto reared his arm back. The other pointed at the sky, giving him the pose of an Olympic javelin thrower. "Tell me what space feels like, would ya?"

"Huh?" Naruto launched the unfortunate giant with all of his might, sending him off like a rocket with a crack against the sound barrier. "AHHHHHHHHHhhhhhhhhhhhhh!"

Mismatched eyes fell away from the distanced giant and locked back onto the forces he was blocking with his body. Fists the size of small sedans came together over his chest and fingers as large as a mortal was tall interlocked before the knuckles that kept them intact cracked like boulders falling in an avalanche. He grinned a toothy grin when he spotted a few monsters scramble back.

"What's wrong? Doesn't anyone want to go next?"

"What the fuck was that!?" An oily haired teen demanded as he stormed into the Titan's Demigod Forces command tent, his helmet yanked from his head and a snarl on his face. The two demigods inside the tent looked up from their map.

"...You're going to have to be a little more specific, Todd." The lanky, brown haired teen drawled. His left hand was set on a notebook that had intricate runes on it, the other pointing at something on the map.

"Spare me, Alakazam!" Todd Shanner sneered. He tossed his helmet on the ground and pointed out toward the battle behind him. "Didn't either of you see what happened to the 59th Street Bridge?"

"We got the report. It was destroyed, correct?" The second teen was lacking an eye and had a wiry build.

"Yeah, no shit it was destroyed, Ethan! That freak Namikaze became a fuckin' skyscraper!" Todd snarled. He ran his hand through his hair with a growl. "How the fuck are we supposed to fight a giant that's bigger than our giants?!"

Ethan Nakamura and Alabaster C. Torrington looked at one another. The latter smirked while the former sighed. He reached into his pocket and pulled out a bill before he slapped it on the table. Alabaster snagged it and stuffed it away.

"Not a word." Ethan warned.

"I wasn't going to say anything…"

"...Did you two fuckin' know he could do that?!" Todd snapped. They looked at him.

"He did it once-"

"Three years before you arrived." Ethan quickly cut in, glaring at the son of Hecate. Then looked back at the son of Enyo. "He never did it again. We didn't think it was likely that he could do it on command."

"Well, he fuckin' learned real fast, didn't he?" Todd growled, arms crossed.

"Don't worry, Todd." Alabaster smirked as he looked back to his notebook, and started to flip through it. He stopped and held it up for the other demigod to see. A cruel grin spread across Todd's face as the mystically gifted demigod finished speaking. "We've got just the thing to use against him."

"This is the way we chuck the monsters, chuck the monsters, chuck the monsters, this is the way we chuck the monsters, early in the morning!" Naruto laughed to himself as he tossed another telekhine to the other side of the East River.

Having seen the damage the colossal demigod had done to a bridge that quite a few of his cabin were fond of, Malcolm Stark of Cabin Six sent him to run interference on the surviving water-based monsters. They managed to get past the East River god's whirlpools and torrents, but were forced to yield when a three hundred foot tall teenager started plucking them from the water and chucking them like they were spoiled crops. As the last telekhine was turned into a makeshift flying fish, the blond demigod dusted his hands off.

"Well, this has been fun." He pursed his lips and looked down at himself, waist deep in the metropolis' no-swim zone without a care in the world. "I wonder how long I can stay like this?"

The record for his shrink time at his smallest - a whopping zero-point-three millimeters! - was about three hours before he had to get to a larger size. He'd already been in 'Colossal Mode' for at most an hour. Maybe two hours then?

Ugh, Naruto scratched his head. If only I could remember how long I was a giant last time! I know it wasn't more than a day. Chiron would've had a cow if that were the case.

While he pondered his first experience with his enlarged state, something so traumatic he subconsciously locked it away, he failed to notice that the far side of the East River had calmed. It was only when he started to hear a commotion from the land behind him that he stirred. Turning to the others, he lifted a hand and waved.

"Hey guys, I got this! Go help another cabin or something!"

The other campers kept waving towards him. Malcolm, easily spotted by the plume on his helmet that marked him as a commander, was handed something that he lifted up to his mouth.

"N-..-o, g-...-t o-..-e w-..-r!"

"What!?" Naruto blinked and took a few steps closer to land, wading through the water as he did. He got closer to the land, the river barely reaching his hips at this point and shivered. The downside to a leather suit that shrank and grew with his body, it retained water. And despite being near the end of summer, it was cold.

"Get out of the water, Naruto!" Malcolm said again, the object in his hand revealed to be a megaphone, evidenced by the feedback that cut through after he spoke.

"Why? I'm winning!"

"Don't argue with me, just get...Naruto watch out!"

There was a loud splash and then there was a sensation of what felt like two dozen knives piercing through his shoulder. Something was biting him! Claws grabbed onto his body and something coiled around his chest. Then came the squeezing.

Worst.

Hug.

Ever.

There was a sickening crunch and more pain flooded through his system. He yelled before his assailant jerked back and pulled them underwater. The East River needed a serious cleaning, it was not fresh. Nor was it salty. Regardless, it burned as it went into his lungs.

Panicking as he drowned, Naruto struggled against his attacker. Whatever it was that had him was as large as he was, but it had gills. And teeth. And claws. And oh, for the love of the gods did he wish he had gills right now!

Air. Need! Air!

His left arm got loose and he used it to regain a semblance of control. He swam up to breach the surface, sucking in lungfuls of air and coughing out the water that almost ended him. The monster that had him pulled him back down, but not before he managed to close his mouth.

Naruto couldn't hold his breath forever, especially while he was being thrashed about like an alligator's chew toy. So, his left fist started swinging wildly. The claw that was digging into his sternum got a serious whump, but it was the head that was chomping down on his shoulder that took even more damage. Three blows knocked a few teeth loose, and another two managed to stun the whatever-it-was into letting go. A sixth and final blind shot to a series of gills made it retreat, releasing the blond and allowing him to drunkenly swim towards Manhattan.

He broke the surface and collapsed against the wall, the fence that stopped Manhattanites from casually strolling off the edge snapping under his arm like a toothpick.

"Naruto!" Through blurry blue and green eyes, Naruto found the speaker. Malcolm was rushing towards him, his cabin mates in tow.

"Hey guys! Malcolm, so glad you could make it!" He turned to brace his back against the wall and groaned before he sought out his attacker. A large red fin was swimming towards him and he rolled his neck, cracking it, before he pushed himself back to his feet. "Hold that thought, Shell-head. I got a fish to fry."

"Naruto, you can't just fight that thing, it's a Cetus!"

"It's about to be Fish Sticks!" Naruto shot back, glaring at the monster as its head broke the surface. Golden eyes glared back and a series of razor-sharp teeth gleamed at him with a smile. He held his hands up when it breached, jumping at him like a shark would at a seal, and caught the jaws. The leather covering them tore and his skin ripped as the monster's teeth pierced through his palms. The claw-like fins reached for purchase on his body, but he held it away as best he could. Holding it out of the water, he let out a bellow and thrust his foot into the monster's massive eel-like lower body.

The Cetus was knocked back, taking what felt like a good chunk from his hands in the process, but Naruto couldn't worry about that right now. He balled his bleeding hands into fists and held them at the ready. The next time it came at him, he countered with a wild right cross that cost it a few more teeth. He groaned when it turned to come at him again, teeth fully regenerated.

"Oh, c'mon, what's it take to put this thing down?!"

"Perseus used Medusa's head!" Malcolm shouted helpfully.

"Great, you go get some Gorgon head and I'll keep the giant fish stick occupied!" Naruto grumbled as he caught the Cetus' next attack with a choke-hold that lasted for all of three seconds. "Gah, you slimy mother of France!"

"Naruto, you can hit things harder after you're small, right?"

"Well, yeah! It's how I beat Damian in our sparring ma-a-tch!" Naruto hissed when the Cetus snuck behind him and slashed his back with its claws. He spun to hit it again, but it had swam away. He bared his teeth at it and ignored the pulsing from his palms and shoulder. How was he going to beat this thing if it could take his punches?

Not to mention it's way faster than I am. He thought as he shifted out of the way from the next charge. I need to hit it fast and hard, but I can't do that when I'm this size! If I was smaller, I could-Wait. That's it!

Naruto grinned as he countered the Cetus' attempt at chomping on him again. He had a plan now, but it would only work if he did it just right.

On the next go around, Naruto braced himself. When it breached the surface, he met its gaze. When its jaws opened, he narrowed his eyes. When its body lifted out of the water, he made his move. The jaws were wide open when he suddenly shrunk down to the size of an ant, and his world was encased in darkness. He was suspended in the air for a good second before he landed with a grunt on the slimy wriggling mass that was the tongue.

"Yeah. Okay, gross decision." Naruto grunted, making a face when he lifted his hand to find it covered in slime. He looked around as best he could, which wasn't saying much. The Cetus' breath smelled foul, no different than when he was big and being bitten by it. Now he was no taller than one of its taste buds and damn he regretted this plan already. Shaking the slobber off of his palm, Naruto stood up and started to move towards the back of the monster's mouth. The throat was cavernous, and the smell of death and decay only got stronger with each step.

Finally, he reached the opening of the monster's throat and closed his eyes.

"Demeter, please don't think less of me for this, but it's all I got." His request given, Naruto clenched his fists - ignored the pain - and brought back the feelings of fear, anger, and uncertainty. He overcame them. Used them.

Then he grew back to his massive size and ripped the Cetus apart from the inside out.

He landed with a grunt, crouched over the gunk-covered members of Cabin Six, while the monster's two halves dissolved around them. Malcolm stood in the center, his raised sword and armor caked in the residue of the Cetus. The grey-eyed blond looked at the giant demigod. He blinked and then dropped his sword. Many others followed his example before they started groaning at their current state of being.

"Uh...hey, Malcolm. How goes the fight?"

"...You were supposed to shrink and then grow to punch it harder! Not go on a freaking suicide mission!" Malcolm snapped.

"Oh. Heh, yeah. That would've been a lot cleaner." Naruto chuckled sheepishly and scratched his head, pulling a piece of Cetus out of his hair. He made a face before looking at the other members of cabin six and smiling weakly. "Um...Anyone up for seafood? I make a mean Cetus Creole."

And that's a wrap for now!

...Until I get inspired by a different cultural reference for the next godly parent.

*eyeballs the Greek God on Life Support*

REFORESHADOWINGINTENSIFIES