They continued on their way across the open water, pegasi and dragon still edgy after their encounter with Momus, each giving the occasional nicker of agitation if they got too close to each other. Jason watched on as Frank moved up in the group to fly beside Hazel, his shoulders hunched and his head bent as if he were trying to talk to her, she staring straight ahead and barely registering his presence.
Jason felt guilty. Hazel was right, of course. He hadn’t had any control over what he was saying, but even still, he couldn’t understand how he had so easily let the words slip out of his mouth.
He hated the way he had felt when he was around Momus, the way they all had felt, for it had clearly been bothering all of them. The demigods were still a little too cautious, a little too quiet.
All that was, except for Leo.
The son of Hephaestus was yammering away about his invention, the PercAnnaLeoamatic 3000 as he was calling it.
“Did you all see that?” he repeated for the umpteenth time. “I mean, he totally fell for that. That was some high stylin’ improv right there!”
“Proud of yourself, are you?” Jason muttered. Thankfully no one heard him, though Piper threw him a worried glance at his dark expression.
I must still be being effected, he thought with a sigh. He hated it when he couldn’t control his emotions, and this kind of thing seemed to be happening more than usual.
The dark landmass behind them was soon just a distant memory and the sea reverted back to its usual monotony.
“Percy, where are we?” Jason yelled, drawing up beside Blackjack.
“Almost there,” he said, though Jason didn’t like the grim way he said it. “30°N, 57°W. My father’s old palace turned hangout of crazy titans. Ready?”
“Set,” Jason shrugged.
“Go.” Percy patted Blackjack on the neck and whispered something to him. The pegasus must not have liked whatever his rider said because he shook his head and huffed in protest. Percy nodded to Jason. “Tell everyone we’re here and to get ready. We’re going to start going down.”
Jason turned out, gliding back around to the others and spreading the message. He didn’t really know what Percy had in mind, but considering he and Jason were the only two that could last underwater, this was beginning to get much more interesting.
The others looked skeptical but didn’t question the supposed plan - perhaps they’d see what Percy was thinking before jumping into the water but they trusted him.
Calypso was the only one who said anything after Jason had gone back to Percy to gather the rest of the plan.
“He does know we can’t go in the water, right?” she said, a sneer in her voice.
“Yes, of course he does,” Annabeth shot back. “He has a plan and knows what he’s doing. We just have to trust him. If you have a problem with that, you can stay up here and do what you do best.”
“And what is it that I do best?”
“Look pretty and stay out of the way.”
The two glared at each other as their pegasi descended alongside the others.
“Okay, okay!” Piper said. “Annabeth, Calypso, stop. That’s enough. What we need to worry about now is where we go from here.”
Annabeth nodded in agreement and broke her gaze with Calypso, who scowled and crossed her arms in submission.
At that moment all the pegasi halted twenty feet midair, hovering as best they could as Blackjack flew back through them so Percy could speak.
“Okay, here’s the plan,” he said, glancing at Jason. “Jason and I’ll go down, seeing as we’re the only two that can safely, and scope out the situation. We check it out and come right back. Everyone else stay high. If something comes out of the water, it’s probably going to attack, so stay out of range as much as possible.”
“And, uh, is something going to be coming out of the water?” Leo said. “Like, I don’t know, Ariel or Flounder, Nemo, even?”
“Ha - Ursula, maybe. Just keep your eyes peeled. There’s something powerful here, I can feel it. And I’m getting the idea that it’s not a nice something.”
“And what if something happens? How do we know?” Annabeth said.
“I’ll yell,” he smirked. She looked at him like she was about to push him off his Pegasus. “Yeah no, bad plan. I’ll try and shoot up a geyser or something. Jason can make a storm. We’ll do our best but I promise, nothing is going to happen.” He smiled and Annabeth seemed to relax a little, though that wasn’t saying much. She nodded and her face softened just a bit as she watched Percy and Jason descend away from the group and toward the boiling sea.
Jason and Percy made it down to the ocean’s surface quickly, the pegasi dropping with only mild hesitation as Percy coaxed them closer. Jason watched as the son of Poseidon inspected the water as if it were some fascinating and horrible animal that would lash out if they got too close.
But nothing happened.
“Ready?” Jason nodded.
And they jumped.
The water was frigid, colder than Jason was expecting though why he had expected warmer water in the middle of the Atlantic he didn’t know. Percy seemed to not even notice it, perhaps due to the fact that he didn’t notice it.
Stupid son of the sea god, Jason thought in spite of himself.
The two boys nodded to each other and Percy disappeared beneath the waves. Jason took a deep breath and plunged after him.
Once fully underwater, he forced himself to concentrate, to form the protective kind of air-bubble tornado around his lungs and his body that would keep him alive. Then he propelled himself slowly behind his friend who was waiting several yards away.
The first thing Jason noticed was the emptiness. The feeling of utter abandonment. There was hardly any sea life and the farther they descended the less he could see it was so dark, their path lit only by the dull light of Riptide.
Percy moved confidently ahead though, maneuvering them around any hazards that they ran across, and soon he slowed to a stop. He pointed down and Jason followed his gaze to what appeared to be the top of some great canyon in the sea floor.
Below them, the water actually seemed to be lighter. Jason could just barely make out the shapes of the white marble pillars and corral constructions that littered the sand, and only after a moment did he notice that there was a small pinpoint of light glowing at the center of the old palace.
It spread out in waves of green, rippling across the water and tinting it with the strange turquoise cast.
“Because that looks good for the ocean,” Percy said. Jason attempted a smile but lost it almost immediately as they heard the deep rumbling begin from somewhere below them.
Almost like the ocean is speaking, Jason thought, peering into the black abyss. The light was growing bigger, the rattling stronger, and Percy began to move back towards the rock face behind them, shielding his eyes with his sword, fear etched across his face as the water roared.
Jason remained where he was. He noticed Percy’s apparent distress and part of his brain thought Oh, maybe I should move back too, away from the imminent danger!. The other part, and unfortunately the majority of his brain, registered nothing at all and he instead hovered in a kind of watery haze, seemingly separate from everything around him.
By the time he heard Percy or felt him yanking his arm it was too late.
“Jason! Gods, get back!” The light erupted from the chasm and the two were thrown back against the rock, silt and sand engulfing them as the massive underwater wave slammed across the sea floor.
“Uh, what’s doing that?” Jason said as he tried to regain his balance in the shifting ground.
“You really want an answer to that?”
“It’s Oceanus. At least - I hope it’s Oceanus.”
“You hope it’s a killer titan who wants to destroy us?” Jason said in exasperation.
“Opposed to our other option? Koios? Yeah, I hope it’s the less-killer titan on his way up.”
Almost as soon as the words were out of Percy’s mouth, a massive shadow began to climb from the depths of the now artificially lighted space.
The two demigods braced themselves for the sight of the massive merman - or his trigger-happy brother - and drew their weapons. But the obsidian horns and shimmering tail they were expecting were nothing in comparison to what actually emerged from the chasm.
A massive jaw filled with rows upon rows of horribly needle sharp teeth consumed the vast space before them. The rest of its head was hidden behind its snaky body which climbed down into the depths the gods knew how far.
“So Oceanus is having a real bad day it seems,” Jason said. “What is that?”
“I’ve no idea - something.”
Jason and Percy scrambled to press themselves up against the rock again, but the undercurrent from the beast as it rose ceaselessly higher and higher into the open ocean was too strong for them to stay rooted down.
One look to Percy and Jason knew they were thinking the same thing.
We need to get back up.
How they would do that without drawing attention to themselves was the question. No way did Jason want that thing on his tail. He might be able to propel himself decently enough through the water, but by no means would he be able to outrun the Loch Ness monster’s ancient relative.
“That way,” Percy said as quietly as possible and began to creep sideways along the wall back the way they’d come. In this fashion they made it pretty far, foot over foot, hand over hand, like some modified freestyle. Jason almost thought they’d make it. That is, until he caught a loose patch of stone and sent it tumbling down the slope. It crashed with such a force that it knocked down more rock and pillar remnants as it fell. It wasn’t extraordinarily loud, but needless to say, it was much louder than Jason would have liked. It was also apparently loud enough for the monster.
The ugly brute reared its head and snarled an earth shattering growl, something very otherworldly that made everything, every atom of Jason’s body tingle as if they were splitting of their own accord.
“Hades,” Percy said, barely a whisper.
“Second that,” Jason mumbled. “Run?”
Surprisingly enough, they made it most of the way back to the surface before the something had even cleared the pitch black of the chasm. Apparently, its titanic size was not working for its benefit, which was perfectly alright with Jason.
They broke the surface and looked around desperately for the pegasi.
“Blackjack!” Percy yelled and almost immediately the dark form above became visible as it raced to meet them. “We need to get back to the others,” he said as he propelled himself out of the water and onto the pegasus’ back. “We need to figure this thing out before we can face it.” Jason got a boost on behind Percy and they started up to join the rest of the demigods who hovered nervously nearby.
“Jason!” Piper yelled over the beating of frantic wings. “What happened?”
“A something came out at us,” he said, knowing it sounded stupid but too frightened to care.
“A something?” Annabeth repeated sarcastically. “Oh wow, that’s really insightful. Thank you for sharing, Son of Jupiter.”
“That’s what it was,” Percy said. “Well, obviously it has a name, but I mean, I think something fits it pretty nicely.”
Jason and Percy nodded. “Thought it’d be Oceanus, but all of a sudden there it was - ”
“The something,” Piper said.
“Yes, the something. Give us a break, Pipes. It was big and loud and had a lot of teeth so yes. We called it a something.” Jason shrugged. “But that doesn’t really matter because it was still following us and it didn’t look like it was ready to stop.”
“But an ocean creature wouldn’t really follow us out of the water,” Calypso said. “And even if it did, it wouldn’t be able to reach us, surely.”
“I wouldn’t count on it,” Percy said. “This thing was massive. We didn’t even see all of it before we escaped. But it looked slow. That could work to our advantage at least.”
As if to prove him wrong, the monster broke the surface of the water below at terminal velocity and continued to rocket skyward. The pegasi panicked and began to climb as quickly as their wings could carry them, and Festus shot a fireball in surprise before making the ascent himself.
“Oh my gods,” Annabeth said. “That can’t be.”
Jason was about to ask what she meant when Blackjack bolted behind the others, not bothering to listen to Percy and both boys were forced to hold on until the pegasus slowed.
Annabeth was right behind them and it was only then that they saw the massive beast was sinking back into the water, perhaps getting ready to try again.
“What, Annabeth?” Percy gasped. “What is that thing?”
“A monster I didn’t know still existed. It was your father’s little ‘pet’ if you will, meaning he created it and had control over it. It must have been hiding in the ruins ever since the battle, not wanting to be bothered. But now that it’s awake - It’s name is Cetus.”