The Battle of the Labyrinth

at the forge of Hephaestus.
    There was no floor, just bubbling lava hundreds of feet below. We stood on a rock ridge that circled the cavern. A network of metal bridges spanned across it. At the center was a huge platform with all sorts of machines, cauldrons, forges, and the largest anvil I’d ever seen—a block of iron the size of a house. Creatures moved around the platform—several strange, dark shapes, but they were too far away to make out details.
    “We’ll never be able to sneak up on them,” I said.
    Annabeth picked up the metal spider and slipped it into her pocket. “I can. Wait here.”
    “Hold it!” I said, but before I could argue, she put on her Yankees cap and turned invisible.
    I didn’t dare call after her, but I didn’t like the idea of her approaching the forge on her own. If those things out there could sense a god coming, would Annabeth be safe?
    I looked back at the Labyrinth tunnel. I missed Grover and Tyson already. Finally I decided I couldn’t stay put. I crept along the outer rim of the lava lake, hoping I could get a better angle to see what was happening in the middle.
    The heat was horrible. Geryon’s ranch had been a winter wonderland compared to this. In no time I was drenched with sweat. My eyes stung from the smoke. I moved along, trying to keep away from the edge, until I found my way blocked by a cart on metal wheels, like the kind they use in mine shafts. I lifted up the tarp and found it was half full of scrap metal. I was about to squeeze my way around it when I heard voices from up ahead, probably from a side tunnel.
    “Bring it in?” one asked.
    “Yeah,” another said. “Movie’s just about done.”
    I panicked. I didn’t have time to back up. There was nowhere to hide except . . . the cart. I scrambled inside and pulled the tarp over me, hoping no one had seen me. I curled my fingers around Riptide, just in case I had to fight.
    The cart lurched forward.
    “Oi,” a gruff voice said. “Thing weighs a ton.”
    “It’s celestial bronze,” the other said. “What did you expect?”
    I got pulled along. We turned a corner, and from the sound of the wheels echoing against the walls I guessed we had passed down a tunnel and into a smaller room.
    Hopefully I was not about to be dumped into a smelting pot. If they started to tip me over, I’d have to fight my way out quick. I heard lots of talking, chattering voices that didn’t sound human—somewhere between a seal’s bark and a dog’s growl. There were other sounds too—like an old-fashioned film projector and a tinny voice narrating.
    “Just set it in the back,” a new voice ordered from across the room. “Now, younglings, please attend to the film. There will be time for questions afterward.”
    The voices quieted down, and I could hear the film.
    As a young sea demon matures , the narrator said, changes happen in the monster’s body. You may notice your fangs getting longer and you may have a sudden desire to devour human beings. These changes are perfectly normal and happen to all young monsters.
    Excited snarling filled the room. The teacher—I guess it must have been a teacher—told the younglings to be quiet, and the film continued. I didn’t understand most of it, and I didn’t dare look. The film kept talking about growth spurts and acne problems caused by working in the forges, and proper flipper hygiene, and finally it was over.
    “Now, younglings,” the instructor said, “what is the proper name of our kind?”
    “Sea demons!” one of them barked.
    “No. Anyone else?”
    “Telekhines!” another monster growled.
    “Very good,” the instructor said. “And why are we here?”
    “Revenge!” several shouted.
    “Yes, yes, but why?”
    “Zeus is evil!” one monster said. “He cast us into Tartarus just because we used magic!”
    “Indeed,” the instructor said. “After we made so many of the gods’ finest weapons. The trident of Poseidon, for one. And of course—we made the greatest weapon of the Titans! Nevertheless, Zeus cast us away and relied on those fumbling Cyclopes. That is why we are taking over the forges of the usurper Hephaestus. And soon we will control the undersea furnaces, our ancestral home!”
    I clutched my pen-sword. These snarling things had created Poseidon’s trident? What were they talking about? I’d never even heard of a telekhine.
    “And so, younglings,” the instructor continued, “who do we serve?”
    “Kronos!” they