I led the charge out the door and up the slippery stairs, wet from the lashing rain. The sight that beheld us, however, stopped me in my tracks for a second. The sky, dark as night from the storm clouds that stretched horizon to horizon, was lit by a split second of lightning, illuminating the scene perfectly. A huge, towering neck, topped by a gaping mouth of razor teeth and slit eyes that promised pain, loomed over the ship, gaze focussed on the two figures silhouetted below it, crouched on deck helplessly. Alexa stood before Annabeth, who was still too weak to leave the deck chair, pale hair silver in the lightning flash, hand holding out her dagger, defensive but ineffectual. Before I could register everything, the lightning had disappeared, and I couldn't see anything anymore. Rain whipped around us, the wind cutting into our quickly soaked clothes as we spread out. Taking my cue from Jason, who was gesturing at the sky as if to pull apart the storm, I jumped neatly over the edge of the boat, and almost drowned before I realised I could breathe, panic blocking my power for one terrifying moment.

It felt amazing. Being in the water seemed to sharpen my senses. Every little injury disappeared, and I was immediately in my element, power coursing through my veins as I breathed deep, and swam forward, propelled by the waves nearly effortlessly. My head cleared, and I could feel every little thing in the water, even the molecules linking the liquid together. I thrummed in harmony with the sea, and cast forward, searching for the monster. It wasn't hard to find, a huge disturbance in the water, rocking back and forth as it fended off blows from above. Taking a deep breath of water, I held out my hand and felt the familiar tug in my gut as I yanked on that patch of ocean, rocking it wildly as the sea serpent struggled, trying to resist.

Somehow, that was the last straw. Eris thought she could take over camp, try to take down the world, but that wasn't enough for her, no, she had to hurt my friends, stalk us all the way from camp, and then try to kill us just when I'd gotten everyone caught up. That was just...rude, and impolite. Somehow, my desperation and panic turned to hot anger burning in the pit of my stomach, and the ocean seemed to swell with me as I rose up, riding the waves easily until I was eye to eye with the monster. Then, curling my fingers into claws and allowing the waves to mimic the movement, I used precise strokes of barely contained fury to take the serpent apart, peeling scaly skin off like a banana and exposing waterfalls of thick black blood that hissed as it touched the surface of the water. Slowly, with water as my instruments, I dissected the monster, peeling flesh from bone and muscle and organ as it writhed and screamed in agony, until I ripped the vocal chords from its throat. Finally, the bones had been divested of flesh, and all that was left was the bones, the skeleton held up by watery tendrils. I grinned a fierce, cold smile, and leaned forward. "Give Eris my love." Then with a clench of my fist, the water turned the bone to powder, floating away on the bob of the waves.

All of a sudden, my head swam, and I realised the water that was holding me up was streaming down, despite my best efforts to hold them there. As my vision began to fade (again! honestly, for the umpteenth time?), I tipped forward, aiming for the deck. They'd be able to nurse me back to health there.

As it were, I was close, missing the ship by an inch, and then my body hit the water and the world was abruptly black.

-

I opened my eyes, slowly swimming to consciousness, and was rewarded with a massive, splitting pain that pulsed behind my eyes and shook my skull. "Gods!" Abruptly, there was a shadow cast over me, and a cool feeling began to soothe the agony. Struggling to open my eyes, I squinted up at the shape, which slowly cleared into a merman, complete with arched cheekbones and delicate, angled features. He was staring down at me, expression carefully neutral, and his fingers rested on my temples, ostensibly healing my injuries. Slowly, I passed back out again, not really caring. If this merman had wanted to kill me, he had ample opportunity before, so either they were under Poseidon's rule, or they were waiting for me to get back on my feet before ending me. Either way, it wasn't a problem for now, so I gratefully let the aching darkness on the edges of my vision take over.

-

The next time I came to, I was lying in the same bed, this time alone. Sitting up gingerly, I grimaced at the dull ache that pervaded my entire body. The reason for it was clear, blue, yellow and purple bruises and contusions up and down the entire length of my body reminded me. I muffled a groan and swung my feet down, allowing the water to almost-but-not-quite support me as I stood and snagged the horn of nectar that was sitting on the bedside table.

Outside stood the same merman, arms crossed and sculpted features arranged in an expression that managed to be both aloof and disdainful. Noticing me, he bowed fractionally and swam away, looking back now and then as if expecting me to follow. Jeez, this guy needed to learn to express himself through his words. Last I checked, mermen weren't mute. Still, I trailed along. I needed him to show me where my dad was, presuming he did answer to Poseidon, so that he could help me get back to the ship. Without my guidance, it was probably lost at sea, and while Piper's cornucopia would ensure they didn't starve, time was running out. Sooner or later, Eris would make a move against Olympus, and that would almost certainly not end well. If a demigod and a god together could end a Titan, then I didn't want to think about what havoc a demigod and a primal force from before the Golden Era could wreck together.

Fortunately, it turned out that the merman was indeed under my dad's command, as he led me to a merlon atop a sunken castle that looked suspiciously like the sandcastles I used to build when I was a kid at Long Island, except scaled up to life size. On it stood a man with regal, flowing black hair held down by a gold circlet, dressed entirely in iridescent blue armour that seemed to shimmer and flow with the water around it and clenching in his hand a dull gold trident, moss twining around patches of the weapon. At the bottom, I could see a few lucky barnacles, hanging on for dear life as he banged the stick against the ground and growled.

"Dad!" I called, and Poseidon turned, shifting as he did. What had once been armour and a circlet was now normal dad fishing gear, and his trident had elongated into a fishing rod. A tired smile split his face, and he walked forward, enveloping me in a hug that smelled of saltwater and felt like home.

"How are you, Percy? You took that fall pretty hard."

"Yeah, uh, I was fighting this massive sea monster."

"Yes, I've heard." Poseidon's eyebrows drew together in an impressive frown, and I couldn't help asking, "What did you hear?"

"That an ancient force is awake and about again, and that even the gods' powers can barely harm her. She is wickedness, evil in its purest form. Only such a creature could feed off strife."

"Then you know we need help. If we work together again, we could bring her down, right? Nothing can stop a demigod and a god working together."

"Percy, some things are more powerful than even that. A god and a demigod will always conflict, even if it's unconscious. We're just too different." Poseidon finished his sentence, but looked thoughtful, so I took a risk and kept on. If this could help retake the camp, it would be worth anything my dad could throw at me. "Is there anything that could help, then?"

"In the past, the evil was once defeated by the unification of two gods working through one demigod, but they had to truly meld. Then, they were united by the threat of the evil, and yet it still wasn't enough to banish her. Now... it would have to take a miracle to ever accomplish anything like that again." I swallowed, but nodded. It wasn't the ideal answer, but it would have to do. "So, would you be willing to do it again?"

Poseidon looked at me then, sea-aqua eyes assessing, and reached around his neck for a necklace, placing it over my head. The leather thong it hung on held an egg-shaped object, colours shifting like sunlight on waves. "History repeats itself. Even if that was not the most pleasant of experiences, I would do it. In the name of destroying that evil, I would not hesitate."

I nodded, grin too wide to speak around. "Thanks, Dad!" He just smiled, tousling my hair. "All I ask is that you tell me who this boy is. Nico di Angelo, yes?'

I could almost feel the blush heat my cheeks, but I nodded. "Yeah, dad. Um, I really love him."

"Son of Hades?" I nodded, and Poseidon's expression grew unreadable. It could've been longing, wistful, sad, regretful, or any combination of the above, and for a split second, I wondered...

But Poseidon was already gesturing at the merman, who stood by stoically. "Mermando will lead you back to your ship. Try not to get the bends."

"I'll do my best. Thanks again for everything, Dad."

Following the expressionless merman (with a name like Mermando, he'd probably needed to learn some zen pretty fast), I considered the new information. I had Poseidon on my side, now all I needed was another god who was willing to meld minds with me and my dad and destroy Eris, as well as a common threat strong enough to unite all of us.

The question was, who would it be?

A/N:

So.

Hey, friends.

Please don't throw things at me.

Okay, but for real I'm super sorry about not updating, just that life is fricking crazy right now (i shouldn't even be doing this damnit) and has been for the past, uh, year, so :D

Sorry for the cliffhanger (again), and no promises this time about the next update, yeah? My exams are coming up really really soon and I need to get my shit together, so. Love y'all!

-n

ps. as an apology, ive written a nice fluff oneshot called tea and toast for all you pernico shippers. hope you enjoy!