Standing at the summit was a mountain god — one of the numina montanum, Jason had called them. Or ourae, in Greek. Whatever you called them, they were nasty.

Like the others they had faced, this one wore a simple white tunic over skin as rough and dark as basalt. He was about 20 feet tall and extremely muscular, with a flowing white beard, scraggly hair, and a wild look in his eyes, like a crazy hermit. He bellowed something Hazel didn't understand, but it obviously wasn't welcoming. With his bare hands, he pried another chunk of rock from his mountain and began shaping it into a ball.

The scene disappeared in the fog, but when the mountain god bellowed again, other numina answered in the distance, their voices echoing through the valleys.

"Stupid rock gods!" Leo yelled from the helm. "That's the third time I've had to replace that mast! You think they grow on trees?"

Nico frowned. "Masts are from trees."

"That's not the point!" Leo snatched up one of his controls, rigged from a Nintendo Wii stick, and spun it in a circle. A few feet away, a trapdoor opened in the deck. A Celestial bronze cannon rose. Hazel just had time to cover her ears before it discharged into the sky, spraying a dozen metal spheres that trailed green fire. The spheres grew spikes in midair, like helicopter blades, and hurtled away into the fog.

A moment later, a series of explosions crackled across the mountains, followed by the outraged roars of mountain gods.

Rick Riordan