Leo's dream started like this.

He was in a dark cavern, Greek Fire dimly illuminating his surrounding in an ominous light. His heart pounded like a thousand drums, a war cry as he charged another nightmare.

Curious, he surveyed what little he could of his mysterious surrounding, pressing a hand to the wall. He pulled away after feeling the damp, harsh texture of stone. Above him, he could make out the slow but constant dripping of water.

Leo wasn't sure when he became a vivid dreamer, but, regardless, he wasn't a fan.

A low croak escaped the darkness, "... Leo?"

He recognised that voice.

Leo crept forwards, a familiar grin falling upon his face. Slowly, the features of one Percy Jackson came into focus, green light eerily washing over him, "Leo! You're actually here!"

"Actually, I'm pretty sure I'm dre–"

"No time!" he whispered, his eyes dancing with excitement, "Look, you need to listen to me! Sometime soon, if I'm right, the gods are going to get rid of me. Whatever happens, please believe I'm innocent. A lot of bad things are coming and you need to be ready! Build a tracker of some sort – you'll need it! And whatever you do, don't trust the Night! Don't tru–"

Percy stopped himself, staring intently at Leo.

Leo nervously grinned at him, taking a moment to observe his rambling friend.

Dried blood coated Percy's forehead with matching cuts and bruises littering the rest of his face. The son of Poseidon also sported a busted nose that Leo was pretty sure was broken in at least two places. Contrastingly, his eyes almost shone with excitement, so bright that it was almost impossible to notice the shadows darker than coal that hung beneath his eyes.

Percy looked like a man gone mad, but a small voice in Leo's head told him that his friend was telling the truth.

"... Leo?"

"Yeah?" he dragged himself away from his thoughts.

"You need to stay safe," Percy's voice had grown soft. "Everyone else is going to believe what the gods say, and that's why I need you to believe me, please. I don't know what else I can do! Just believe me – please! And what ever you do, don't trust the Night!"

Leo hesitantly nodded, "I promise, dude, but what's going on?"

"I wish I could tell you but I don't even know, myself, at this point. Too much has happened..."

"Then at least tell me who's the Ni–"

A dark cackle tore through the cave, shaking it to its very foundations. We both froze, caught like deers in headlights.

"She's here!" Percy cursed, "You need to go!"

"I don't even know how I got here! How do I leave? And who's the–"

"There's no time! You need to wake up, Leo! Wake up!"

"How do I do that?" Leo felt like an idiot.

"I... hide!"

Leo pressed himself against a wall just before the lights went out. He heard the dark laugh once more as Percy cried out, his voice growing far away.

"My, my, has someone brought me a new plaything?" The voice distorted and grew closer to Leo, or at least that's what he thought. The unknown voice could have been a metre or a mile away and he wouldn't have noticed in the darkness.

A second later, a large hand wrapped around him, colder than any snowball he'd ever thrown. Leo yelped and lit himself alight.

The darkness retracted.

"You can only hold me back for so long, demigod!" the voice growled, "You'll all fall!"

Leo bit back a snarky remark.

"Leo, run! G–" Percy's cry turned into a shout of pain.

"Percy!" Leo fell into darkness.