The Last Olympian

enemy demigods. No matter how many I defeated, more took their place.
    Annabeth and I raced from block to block, trying to shore up our defenses. Too many of our friends lay wounded in the streets. Too many were missing.
    As the night wore on and the moon got higher, we were backed up foot by foot until we were only a block from the Empire State Building in any direction. At one point Grover was next to me, bonking snake women over the head with his cudgel. Then he disappeared in the crowd, and it was Thalia at my side, driving the monsters back with the power of her magic shield. Mrs. O’Leary bounded out of nowhere, picked up a Laistrygonian giant in her mouth, and flung him into the air like a Frisbee. Annabeth used her invisibility cap to sneak behind the enemy lines. Whenever a monster disintegrated for no apparent reason with a surprised look on his face, I knew Annabeth had been there.
    But it still wasn’t enough.
    “Hold your lines!” Katie Gardner shouted, somewhere off to my left.
    The problem was there were too few of us to hold anything. The entrance to Olympus was twenty feet behind me. A ring of brave demigods, Hunters, and nature spirits guarded the doors. I slashed and hacked, destroying everything in my path, but even I was getting tired, and I couldn’t be everywhere at once.
    Behind the enemy troops, a few blocks to the east, a bright light began to shine. I thought it was the sunrise. Then I realized Kronos was riding toward us on a golden chariot. A dozen Laistrygonian giants bore torches before him. Two Hyperboreans carried his black-and-purple banners. The Titan lord looked fresh and rested, his powers at full strength. He was taking his time advancing, letting me wear myself down.
    Annabeth appeared next to me. “We have to fall back to the doorway. Hold it at all costs!”
    She was right. I was about to order a retreat when I heard the hunting horn.
    It cut through the noise of the battle like a fire alarm. A chorus of horns answered from all around us, echoing off the buildings of Manhattan.
    I glanced at Thalia, but she just frowned.
    “Not the Hunters,” she assured me. “We’re all here.”
    “Then who?”
    The horns got louder. I couldn’t tell where they were coming from because of the echo, but it sounded like an entire army was approaching.
    I was afraid it might be more enemies, but Kronos’s forces looked as confused as we were. Giants lowered their clubs. Dracaenae hissed. Even Kronos’s honor guard looked uneasy.
    Then, to our left, a hundred monsters cried out at once. Kronos’s entire northern flank surged forward. I thought we were doomed, but they didn’t attack. They ran straight past us and crashed into their southern allies.
    A new blast of horns shattered the night. The air shimmered. In a blur of movement, an entire cavalry appeared as if dropping out of light speed.
    “Yeah, baby!” a voice wailed. “PARTY!”
    A shower of arrows arced over our heads and slammed into the enemy, vaporizing hundreds of demons. But these weren’t regular arrows. They made whizzy sounds as they flew, like WHEEEEEE! Some had pinwheels attached to them. Others had boxing gloves rather than points.
    “Centaurs!” Annabeth yelled.
    The Party Pony army exploded into our midst in a riot of colors: tie-dyed shirts, rainbow Afro wigs, oversize sunglasses, and war-painted faces. Some had slogans scrawled across their flanks like HORSEZ PWN or KRONOS SUX .
    Hundreds of them filled the entire block. My brain couldn’t process everything I saw, but I knew if I were the enemy, I’d be running.
    “Percy!” Chiron shouted across the sea of wild centaurs. He was dressed in armor from the waist up, his bow in his hand, and he was grinning in satisfaction. “Sorry we’re late!”
    “DUDE!” Another centaur yelled. “Talk later. WASTE MONSTERS NOW!”
    He locked and loaded a double-barrel paint gun and blasted an enemy hellhound bright pink. The paint must’ve been mixed with Celestial bronze dust or something, because as soon as it splattered the hellhound, the monster yelped and dissolved into a pink-and-black puddle.
    “PARTY PONIES!” a centaur yelled. “SOUTH FLORIDA CHAPTER!”
    Somewhere across the battlefield, a twangy voice yelled back, “HEART OF TEXAS CHAPTER!”
    “HAWAII OWNS YOUR FACES!” a third one shouted.
    It was the most beautiful thing I’d ever seen. The entire Titan army turned and fled, pushed back by a flood of paintballs, arrows, swords, and NERF