“No,” I tried again, halfway up the hill. “This monster is a petsuchos—a son of Sobek.”

“Who’s Sobek?” he asked.

“The lord of crocodiles. Egyptian god.”

That stopped him in his tracks. He stared at me, and I could swear the air between us turned electric. A voice, very deep in my mind, said: Shut up. Don’t tell him any more.

Percy glanced at the khopesh I’d retrieved from the river, then the wand in my belt. “Where are you from? Honestly.”

“Originally?” I asked. “Los Angeles. Now I live in Brooklyn.”

That didn’t seem to make him feel any better. “So this monster, this pet-suck-o or whatever—”

“Petsuchos,” I said. “It’s a Greek word, but the monster is Egyptian. It was like the mascot of Sobek’s temple, worshipped as a living god.”

Percy grunted. “You sound like Annabeth.”

“Who?”

“Nothing. Just skip the history lesson. How do we kill it?”

“I told you—”

From above came another scream, followed by a loud CRUNCH, like the sound made by a metal compactor.

We sprinted to the top of the hill, then hopped the fence of somebody’s backyard and ran into a residential cul-de-sac.

Except for the giant crocodile in the middle of the street, the neighborhood could have been Anywhere, USA. Ringing the cul-de-sac were half a dozen single-story homes with well-kept front lawns, economy cars in the driveways, mailboxes at the curb, flags hanging above the front porches.

Unfortunately, the all-American scene was kind of ruined by the monster, who was busily eating a green Prius hatchback with a bumper sticker that read MY POODLE IS SMARTER THAN YOUR HONOR STUDENT. Maybe the petsuchos thought the Toyota was another crocodile, and he was asserting his dominance. Maybe he just didn’t like poodles and/or honor students.

Whatever the case, on dry land the crocodile looked even scarier than he had in the water. He was about forty feet long, as tall as a delivery truck, with a tail so massive and powerful, it overturned cars every time it swished. His skin glistened blackish green and gushed water that pooled around his feet. I remembered Sobek once telling me that his divine sweat created the rivers of the world. Yuck. I guessed this monster had the same holy perspiration. Double yuck.

The creature’s eyes glowed with a sickly yellow light. His jagged teeth gleamed white. But the weirdest thing about him was his bling. Around his neck hung an elaborate collar of gold chains and enough precious stones to buy a private island.

The necklace was how I had realized that the monster was a petsuchos, back at the marsh. I’d read that the sacred animal of Sobek wore something just like it back in Egypt, though what the monster was doing in a Long Island subdivision, I had no idea.

As Percy and I took in the scene, the crocodile clamped down and bit the green Prius in half, spraying glass and metal and pieces of air bag across the lawns.

As soon as he dropped the wreckage, half a dozen kids appeared from nowhere—apparently they’d been hiding behind some of the other cars—and charged the monster, screaming at the top of their lungs.

I couldn’t believe it. They were just elementary-age kids, armed with nothing but water balloons and Super Soakers. I guessed that they were on summer break and had been cooling off with a water fight when the monster interrupted them.

There were no adults in sight. Maybe they were all at work. Maybe they were inside, passed out from fright.

The kids looked angry rather than scared. They ran around the crocodile, lobbing water balloons that splashed harmlessly against the monster’s hide.

Useless and stupid? Yes. But I couldn’t help admiring their bravery. They were trying their best to face down a monster that had invaded their neighborhood.

Maybe they saw the crocodile for what it was. Maybe their mortal brains made them think it was an escaped elephant from the zoo, or a crazed FedEx delivery driver with a death wish.

Whatever they saw, they were in danger.

My throat closed up. I thought about my initiates back at Brooklyn House, who were no older than these kids, and my protective “big brother” instincts kicked in. I charged into the street, yelling, “Get away from it! Run!”

Then I threw my wand straight at the crocodile’s head. “Sa-mir!”

The wand hit the croc on the snout, and blue light rippled across his body. All over the monster’s hide, the hieroglyph for pain flickered:

Everywhere it appeared, the croc’s skin smoked and sparked, causing the monster to writhe and bellow in annoyance.

The kids scattered, hiding behind ruined cars and mailboxes. The petsuchos turned his glowing yellow eyes on me.

At my side, Percy whistled under his breath. “Well, you got his attention.”

“Yeah.”

“You sure we can’t kill him?” he asked.

“Yeah.”

The crocodile seemed to be following our conversation. His yellow eyes flicked back and forth between us, as if deciding which of us to eat first.

“Even if you could destroy his body,” I said, “he would just reappear somewhere nearby. That necklace? It’s enchanted with the power of Sobek. To beat the monster, we have to get that necklace off. Then the petsuchos should shrink back into a regular crocodile.”

“I hate the word should,” Percy muttered. “Fine. I’ll get the necklace. You keep him occupied.”

“Why do I get to keep him occupied?”

“Because you’re more annoying,” Percy said. “Just try not to get eaten again.”

“ROARR!” the monster bellowed, his breath like a seafood restaurant’s Dumpster.

I was about to argue that Percy was plenty annoying, but I didn’t get the chance. The petsuchos charged, and my new comrade-in-arms sprinted to one side, leaving me right in the path of destruction.

First random thought: Getting eaten twice in one day would be very embarrassing.

Out of the corner of my eye, I saw Percy dashing toward the monster’s right flank. I heard the mortal kids come out from their hiding places, yelling and throwing more water balloons like they were trying to protect me.

The petsuchos lumbered toward me, his jaws opening to snap me up.

And I got angry.

I’d faced the worst Egyptian gods. I’d plunged into the Duat and trekked across the Land of Demons. I’d stood at the very shores of Chaos. I was not going to back down to an overgrown gator.

The air crackled with power as my combat avatar formed around me—a glowing blue exoskeleton in the shape of Horus.

It lifted me off the ground until I was suspended in the middle of a twenty-foot-tall, hawk-headed warrior. I stepped forward, bracing myself, and the avatar mimicked my stance.

Percy yelled, “Holy Hera! What the—?!”

The crocodile slammed into me.

He nearly toppled me. His jaws closed around my avatar’s free arm, but I slashed the hawk warrior’s glowing blue sword at the crocodile’s neck.

Maybe the petsuchos couldn’t be killed. I was at least hoping to cut through the necklace that was the source of his power.

Unfortunately, my swing went wide. I hit the monster’s shoulder, cleaving his hide. Instead of blood, he spilled sand, which is pretty typical for Egyptian monsters. I would have enjoyed seeing him disintegrate completely, but no such luck. As soon as I yanked my blade free, the wound started closing and the sand slowed to a trickle. The crocodile whipped his head from side to side, pulling me off my feet and shaking me by the arm like a dog with a chew toy.

When he let me go, I sailed straight into the nearest house and smashed through the roof, leaving a hawk-warrior-shaped crater in someone’s living room. I really hoped I hadn’t just flattened some defenseless mortal in the middle of watching Dr. Phil.

My vision cleared, and I saw two things that irritated me. First, the crocodile was charging me again. Second, my new friend Percy was just standing in the middle of the street, staring at me in shock. Apparently my combat avatar had startled him so much, he’d forgotten his part of the plan.

“What the creeping crud is that?” he demanded. “You’re inside a giant glowing chicken-man!”

“Hawk!” I yelled.

I decided that if I survived this day, I would have to make sure this guy never met Sadie. They’d probably take turns insulting me for the rest of eternity. “A little help here?”

Percy unfroze and ran toward the croc. As the monster closed in on me, I kicked him in the snout, which made him sneeze and shake his head long enough for me to extricate myself from the ruined house.

Percy jumped on the creature’s tail and ran up his spine. The monster thrashed around, his hide shedding water all over the place; but somehow Percy managed to keep his footing. The guy must have practiced gymnastics or something.

Meanwhile, the mortal kids had found some better ammunition—rocks, scrap metal from the wrecked cars, even a few tire irons—and were hurling the stuff at the monster. I didn’t want the crocodile turning his attention toward them.

“HEY!” I swung my khopesh at the croc’s face—a good solid strike that should’ve taken off his lower jaw. Instead, he somehow snapped at the blade and caught it in his mouth. We ended up wrestling for the blue glowing sword as it sizzled in his mouth, making his teeth crumble to sand. That couldn’t have felt good, but the croc held on, tugging against me.

“Percy!” I shouted. “Any time now!”

Percy lunged for the necklace. He grabbed hold and started hacking at the gold links, but his bronze sword didn’t make a dent.

Meanwhile, the croc was going crazy trying to yank away my sword. My combat avatar started to flicker.

Summoning an avatar is a short-term thing, like sprinting at top speed. You can’t do it for very long, or you’ll collapse. Already I was sweating and breathing hard. My heart raced. My reservoirs of magic were being severely depleted.

“Hurry,” I told Percy.

“Can’t cut it!” he said.

“A clasp,” I said. “There’s gotta be one.”

As soon as I said that, I spotted it—at the monster’s throat, a golden cartouche encircling the hieroglyphs that spelled SOBEK. “There—on the bottom!”

Percy scrambled down the necklace, climbing it like a net, but at that moment my avatar collapsed. I dropped to the ground, exhausted and dizzy. The only thing that saved my life was that the crocodile had been pulling at my avatar’s sword. When the sword disappeared, the monster lurched backward and stumbled over a Honda.

The mortal kids scattered. One dove under a car, only to have the car disappear—smacked into the air by the croc’s tail.

Percy reached the bottom of the necklace and hung on for dear life. His sword was gone. Probably he’d dropped it.

Meanwhile, the monster regained his footing. The good news: he didn’t seem to notice Percy. The bad news: he definitely noticed me, and he looked mightily torqued off.

I didn’t have the energy to run, much less summon magic to fight. At this point, the mortal kids with their water balloons and rocks had more of a chance of stopping the croc than I did.