“Piper!” Frank yelled. “Counter those empousai! We need some chaos.”

“Thought you’d never ask.” She started catcalling at the female demons: “Your makeup is smeared! Your friend called you ugly! That one is making a face behind your back!” Soon the vampire ladies were too busy fighting one another to shout any commands.

The legionnaires moved forward, keeping up the pressure. They had to take the bridge before Jason got overwhelmed.

“Time to lead from the front,” Frank decided. He raised his borrowed sword and called for a charge.

FRANK DIDN’T NOTICE THAT HE WAS GLOWING. Later Jason told him that the blessing of Mars had shrouded him in red light, like it had in Venice. Javelins couldn’t touch him. Rocks somehow got deflected. Even with an arrow sticking out of his left biceps, Frank had never felt so full of energy.

The first Cyclops he met went down so quickly it was almost a joke. Frank sliced him in half from shoulder to waist. The big guy exploded into dust. The next Cyclops backed up nervously, so Frank cut his legs out from under him and sent him into the pit.

The remaining monsters on their side of the chasm tried to retreat, but the legion cut them down.

“Tetsudo formation!” Frank shouted. “Single file, advance!”

Frank was the first one across the bridge. The dead followed, their shields locked on either side and over their heads, deflecting all attacks. As the last of the zombies crossed, the stone bridge crumbled into the darkness, but by then it didn’t matter.

Nico kept summoning more legionnaires to join the fight. Over the history of the empire, thousands of Romans had served and died in Greece. Now they were back, answering the call of Diocletian’s scepter.

Frank waded forward, destroying everything in his path.

“I will burn you!” a telkhine squeaked, desperately waving a vial of Greek fire. “I have fire!”

Frank took him down. As the vial dropped toward the ground, Frank kicked it over the cliff before it could explode.

An empousa raked her claws across Frank’s chest, but Frank felt nothing. He sliced the demon into dust and kept moving. Pain was unimportant. Failure was unthinkable.

He was a leader of the legion now, doing what he was born to do—fighting the enemies of Rome, upholding its legacy, protecting the lives of his friends and comrades. He was Praetor Frank Zhang.

His forces swept the enemy away, breaking their every attempt to regroup. Jason and Piper fought at his side, yelling defiantly. Nico waded through the last group of Earthborn, slashing them into mounds of wet clay with his black Stygian sword.

Before Frank knew it, the battle was over. Piper chopped through the last empousa, who vaporized with an anguished wail.

“Frank,” Jason said, “you’re on fire.”

He looked down. A few drops of oil must have splattered on his pants, because they were starting to smolder. Frank batted at them until they stopped smoking, but he wasn’t particularly worried. Thanks to Leo, he no longer had to fear fire.

Nico cleared his throat. “Uh…you also have an arrow sticking through your arm.”

“I know.” Frank snapped off the point of the arrow and pulled out the shaft by the tail. He felt only a warm, tugging sensation. “I’ll be fine.”

Piper made him eat a piece of ambrosia. As she bandaged his wound, she said, “Frank, you were amazing. Completely terrifying, but amazing.”

Frank had trouble processing her words. Terrifying couldn’t apply to him. He was just Frank.

His adrenaline drained away. He looked around him, wondering where all the enemies had gone. The only monsters left were his own undead Romans, standing in a stupor with their weapons lowered.

Nico held up his scepter, its orb dark and dormant. “The dead won’t stay much longer, now that the battle is over.”

Frank faced his troops. “Legion!”

The zombie soldiers snapped to attention.

“You fought well,” Frank told them. “Now you may rest. Dismissed.”

They crumbled into piles of bones, armor, shields, and weapons. Then even those disintegrated.

Frank felt as if he might crumble too. Despite the ambrosia, his wounded arm began to throb. His eyes were heavy with exhaustion. The blessing of Mars faded, leaving him depleted. But his work wasn’t done yet.

“Hazel and Leo,” he said. “We need to find them.”

His friends peered across the chasm. At the other end of the cavern, the tunnel Hazel and Leo had entered was buried under tons of rubble.

“We can’t go that way,” Nico said. “Maybe…”

Suddenly he staggered. He would have fallen, if Jason hadn’t caught him.

“Nico!” Piper said. “What is it?”

“The Doors,” Nico said. “Something’s happening. Percy and Annabeth…we need to go now.”

“But how?” Jason said. “That tunnel is gone.”

Frank clenched his jaw. He hadn’t come this far to stand around helplessly while his friends were in trouble. “It won’t be fun,” he said, “but there’s another way.”

GETTING KILLED BY TARTARUS didn’t seem like much of an honor.

As Annabeth stared up at his dark whirlpool face, she decided she’d rather die in some less memorable way—maybe falling down the stairs, or going peacefully in her sleep at age eighty, after a nice quiet life with Percy. Yes, that sounded good.

It wasn’t the first time Annabeth had faced an enemy she couldn’t defeat by force. Normally, this would’ve been her cue to stall for time with some clever Athena-like chitchat.

Except her voice wouldn’t work. She couldn’t even close her mouth. For all she knew, she was drooling as badly as Percy did when he slept.

She was dimly aware of the army of monsters swirling around her, but after their initial roar of triumph, the horde had fallen silent. Annabeth and Percy should have been ripped to pieces by now. Instead, the monsters kept their distance, waiting for Tartarus to act.

The god of the pit flexed his fingers, examining his own polished black talons. He had no expression, but he straightened his shoulders as if he were pleased.

It is good to have form, he intoned. With these hands, I can eviscerate you.

His voice sounded like a backward recording—as if the words were being sucked into the vortex of his face rather than projected. In fact, everything seemed to be drawn toward the face of this god—the dim light, the poisonous clouds, the essence of the monsters, even Annabeth’s own fragile life force. She looked around and realized that every object on this vast plain had grown a vaporous comet’s tail—all pointing toward Tartarus.

Annabeth knew she should say something, but her instincts told her to hide, to avoid doing anything that would draw the god’s attention.

Besides, what could she say? You won’t get away with this!

That wasn’t true. She and Percy had only survived this long because Tartarus was savoring his new form. He wanted the pleasure of physically ripping them to pieces. If Tartarus wished, Annabeth had no doubt he could devour her existence with a single thought, as easily as he’d vaporized Hyperion and Krios. Would there be any rebirth from that? Annabeth didn’t want to find out.

Next to her, Percy did something she’d never seen him do. He dropped his sword. It just fell out of his hand and hit the ground with a thud. Death Mist no longer shrouded his face, but he still had the complexion of a corpse.

Tartarus hissed again—possibly laughing.

Your fear smells wonderful, said the god. I see the appeal of having a physical body with so many senses. Perhaps my beloved Gaea is right, wishing to wake from her slumber.

He stretched out his massive purple hand and might have plucked up Percy like a weed, but Bob interrupted.

“Begone!” The Titan leveled his spear at the god. “You have no right to meddle!”

Meddle? Tartarus turned. I am the lord of all creatures of the darkness, puny Iapetus. I can do as I please.

His black cyclone face spun faster. The howling sound was so horrible, Annabeth fell to her knees and clutched her ears. Bob stumbled, the wispy comet tail of his life force growing longer as it was sucked toward the face of the god.

Bob roared in defiance. He charged and thrust his spear at Tartarus’s chest. Before it could connect, Tartarus swatted Bob aside like he was a pesky insect. The Titan went sprawling.

Why do you not disintegrate? Tartarus mused. You are nothing. You are even weaker than Krios and Hyperion.

“I am Bob,” said Bob.

Tartarus hissed. What is that? What is Bob?

“I choose to be more than Iapetus,” said the Titan. “You do not control me. I am not like my brothers.”

The collar of his coveralls bulged. Small Bob leaped out. The kitten landed on the ground in front of his master, then arched his back and hissed at the lord of the abyss.

As Annabeth watched, Small Bob began to grow, his form flickering until the little kitten had become a full-sized, translucent skeletal saber-toothed tiger.

“Also,” Bob announced, “I have a good cat.”

No-Longer-Small Bob sprang at Tartarus, sinking his claws into Tartarus’s thigh. The tiger scrambled up his leg, straight under the god’s chain-link skirt. Tartarus stomped and howled, apparently no longer enamored with having a physical form. Meanwhile, Bob thrust his spear into the god’s side, right below his breastplate.

Tartarus roared. He swatted at Bob, but the Titan backed out of reach. Bob thrust out his fingers. His spear yanked itself free of the god’s flesh and flew back to Bob’s hand, which made Annabeth gulp in amazement. She’d never imagined a broom could have so many useful features. Small Bob dropped out of Tartarus’s skirt. He ran to his master’s side, his saber-toothed fangs dripping with golden ichor.

You will die first, Iapetus, Tartarus decided. Afterward, I will add your soul to my armor, where it will slowly dissolve, over and over, in eternal agony.

Tartarus pounded his fist against his breastplate. Milky faces swirled in the metal, silently screaming to get out.

Bob turned toward Percy and Annabeth. The Titan grinned, which probably would not have been Annabeth’s reaction to a threat of eternal agony.

“Take the Doors,” Bob said. “I will deal with Tartarus.”

Tartarus threw back his head and bellowed—creating a vacuum so strong that the nearest flying demons were pulled into his vortex face and shredded.

Deal with me? the god mocked. You are only a Titan, a lesser child of Gaea! I will make you suffer for your arrogance. And as for your tiny mortal friends…

Tartarus swept his hand toward the monster army, beckoning them forward. DESTROY THEM!

DESTROY THEM.

Annabeth had heard those words often enough that they shocked her out of her paralysis. She raised her sword and yelled, “Percy!”

He snatched up Riptide.

Annabeth dove for the chains holding the Doors of Death. Her drakon-bone blade cut through the left-side moorings in a single swipe. Meanwhile, Percy drove back the first wave of monsters. He stabbed an arai and yelped, “Gah! Stupid curses!” Then he scythed down a half dozen telkhines. Annabeth lunged behind him and sliced through the chains on the other side.