Nico's optimism lasted approximately twelve minutes.

By then, he was in the principia with Will and Johan, after Will had frantically explained to Hazel why she couldn't come into her own headquarters because Johan was inside, freaking out. The blemmyae had wanted only Nico's help. Hazel had reluctantly agreed on the condition that if Nico, Will, or Johan wrecked her desk or burned down the building, she would string them up by their ankles.

Now Nico stood in the office between Will and Johan, frowning at the latest installment of Nico di Angelo: Disaster Detective.

"Please tell me what I'm looking at," he said.

The blemmyae wrung his hands. "I didn't know what to do! I didn't know!"

In front of them, a demigod was frozen mid-step, as if he'd been petrified while running toward the door. Nico couldn't be sure, but he thought it was the same kid who'd thrown the apple at Johan the previous night. Either that, or it was the creepiest, most realistic statue ever made. The kid's eyes were wide open, his expression stuck somewhere between surprise and terror. Balanced between the fingers of his outstretched hands was a multisided metal object about the size of a baseball.

"How did he end up like this?" Nico asked.

Johan paced nervously, pulling at the hair on his shoulders. "He— I was organizing the principia's archives, cataloging artifacts like we talked about...."

He pointed at the metal security door that, Nico knew, led downstairs to the legion's treasure vaults. "Frank gave me permission! And then this young man"—he gestured at the demigod statue—"came in and said he needed to borrow a magical item."

Nico studied the frozen kid. "The thing he's holding?"

Johan couldn't nod, not having a head, but he did bow several times, reminding Nico of one of those dippy bird toys that can drink from a glass of water.

"It's a dodecahedron," Johan explained.

"That...is a word," said Will. "I don't know what it means."

"It's a shape!" Johan said. "With twelve equal sides!"

"Wait, is it part of a game?" said Nico, who imagined one of the dice from a Mythomagic set, only blown up to much larger proportions. "Are we supposed to roll it?"

"That is not how its magic works," said Johan.

"Wait," said Will. "It's magic, and you just gave it to him?"

"No! Well, yes!" Johan wailed. "He said he had permission. He told me he was studying the god Vulcan's greatest inventions. He said that if I didn't hand it over, we would both get in trouble, and I definitely did not want to get in trouble!"

Will raised a hand. "So he manipulated you. He knew that blemmyae are exceptionally polite, and he took advantage."

Johan straightened his shoulders. "I am very polite."

Nico's headache was coming back. Like most sequels, it was bigger, louder, and more painful. He squinted at the dodecahedron in the legionnaire's hand. "Johan, did he know what he was asking for?"

"I can't be sure," said the blemmyae. "But he was in the process of throwing it at me when he froze this way, so..." The blemmyae's mouth fell open, exposing his abdominal cavity all the way back to his spine. "Oh, dear. Does that mean he was trying to freeze me? And he got the controls wrong? That really wasn't very polite at all!"

Nico didn't know what to say at first. Apparently, this kid had tried to pull a prank on the blemmyae that had ridiculously backfired. Nico was tempted to just leave the demigod frozen there and tell Hazel he was like that when they found him. Maybe the praetors could use him as a toga rack. He doubted Will and Johan would go for that, though. They were both too polite.

"Johan," Will said, "tell us about dodecahedrons, please. How do they work?"

"Oh!" Despite Johan's agitation, his eyes lit up at the chance to share his knowledge. "You see, in recent years, humans have been unearthing these devices, unsure what the Romans used them for. But of course, regular mortals wouldn't understand, would they? Thousands of years ago, Roman demigods designed dodecahedrons to ensnare any mythical creature, or anyone with godly parentage. If you have four or more devices, you can create a perimeter to confine a large number of creatures. If you have a single dodecahedron...well, as you can see, once it is primed, just touching it can trigger paralysis. Which is why this demigod is currently unable to move."

Nico grimaced. "So I guess you don't know how to un-trigger it."

"Of course I do!" Johan looked offended. "One simply has to use all ten fingers to apply pressure simultaneously to ten of the plates, while aligning the remaining two plates toward the target."

If Will had looked any more confused, he would have been turned into a meme with physics equations floating around his face. "So...if you know how to release him, why haven't you?"

Johan stared at him blankly. "Do you think that's what he would want? I'm just so flustered! I thought perhaps he was doing research on what it felt like to be trapped!" He turned to Nico. "I knew you would know what to do. Can you please help me? Then we can all have a nice cup of tea!"

Nico imagined Mr. D's voice in the back of his mind: Breathe, Nico. Do not attempt to strangle the blemmyae. He has no neck.

"Is it safe to touch the dodo-box?" Will asked, examining the device.

"The dodeca—" Johan stopped himself, probably remembering that it wasn't polite to correct people. "Of course. It's already been triggered."

Nico yanked the device from the frozen kid's hands. It was hollow, probably made of copper, with a hole in the middle of each plate and little knobs wherever the corners of three plates met. It definitely was like the twelve-sided die he used for Mythomagic games, only much bigger. He spread his fingertips until each was covering a different plate. Then he pointed the seam between the two remaining plates at the petrified doofus.

"Like this?" he asked Johan.

"That's it," Johan said. "Now if you press..."

Nico did.

The kid unfroze, falling forward onto his outstretched palms.

Nico smiled down at him. "Had a good time, did you?"

"Uhhh..." The camper's eyes darted from Nico to Will to Johan. "I didn't...It wasn't— I was just doing research—"

"On how to play pranks on Johan," Nico supplied. "You should tell your centurion what you did. Your praetors will know about this soon enough, so...maybe get ahead of it."

"I—uh—yes," the kid sputtered. Then he scrambled to his feet and ran from the principia.

"We didn't even get his name," said Will.

"Don't need it." Nico handed the dodecahedron to Johan. "That kid is so scared I don't think he'll cause any more trouble."

Johan twirled the dodecahedron by two of its knobs, which fortunately did not turn any of them into statues. "How badly have I messed up? Will they ever let me work in the archives again?"

Will placed a comforting hand on the blemmyae's shoulder, which was also his forehead. "Hey, what that kid did to you was unfair. You shouldn't have given him anything from the archives, not without Hazel's or Frank's written permission. But live and learn. We all make mistakes."

Johan's eyes widened. "You mean it's not just me?"

Nico smiled. He wasn't sure if Johan was really that naive or if he just had an obtuse sense of humor, but either way, he was starting to appreciate the blemmyae's style.

"I'm still learning this myself," he offered, "but it's actually polite to set boundaries for yourself. You can tell someone no, and it doesn't make you rude."

"Hmm," Johann said. "I'm not sure I understand that."

"It's okay. We can work on it! You can practice with us."

Johan hesitated, and then set the dodecahedron on the praetors' desk. "But not right now. I believe I will go home and brew a pot of tea." He glanced at Nico. "Did I set boundaries correctly?"

"Great job," Nico said.

"Yay!" Johan clapped his hands and bounded out of the office.

Once he was gone, Nico let out a long sigh. "How is it we're not even halfway through the day and I'm already exhausted?"

"Tell me about it," his boyfriend said, leaning his head against Nico's. "What did Hazel need you for earlier, anyway?"

Nico shared what had happened with Orcus on Highway 24, and how he'd left the griffin chatting away with Yazan and Deion.

"That's progress!" said Will. "We are making a difference."

Nico remembered his conversation with Dionysus—how this wasn't a quest, and there was no finish line.

"I hope so," he said. "It's hard to tell."

"Oh, trust me." Will smiled. "I'm usually right."

"You're so old and wise."

"Okay, calm down."

"Deeply, deeply old."

"Aren't we only a year apart?"

Nico didn't know the answer to that, any more than he knew dodecahedrons from dinosaurs. Like Hazel, he'd been born in a different century. He hadn't really aged for most of that time, but he had been conscious and active. So was he a teen, a hundred-year-old fossil, or something in between?

All he knew was that Will was his peer in every way that mattered.

"Come on." He planted a kiss on Will's cheek. "Let's see what other fires we can put out."

As it turned out, the next fire was Arielle's hair.

That afternoon, while Will continued to drill with the Fifth Cohort— which he totally didn't complain about—Nico found himself back on the Field of Mars. Savannah had told him she wanted to give sparring with the empousa another try, and while Nico wasn't sure this was a good idea, he admired Savannah's determination.

It was just the three of them, standing on an expanse of packed dirt under a surprisingly hot winter sun. Sweat beaded on Nico's forehead as he watched the two girls square off with their wooden practice swords.

Savannah had strapped a leather cuirass over her camp tee and leg guards over her jeans. Her long red hair fell loosely across her shoulders. She wore an expression of intense concentration, her green eyes and orange freckles all seeming to gather in the center of her face as she focused on a point just beyond the tip of her nose. She didn't look like someone who'd recently had a full-blown panic attack, but Nico knew appearances could be deceiving.

As for Arielle, Nico was just glad she hadn't fled camp yet. She'd reluctantly agreed to meet Savannah for another round of practice as long as Nico served as referee.

The empousa's flaming hair guttered and flickered in the breeze. She wore a pink tank top and white wide-legged skater pants today, so you couldn't tell she had mismatched legs until you looked at her feet—one bronze, and the other a donkey's hoof. If she'd really spent last night sobbing, Nico couldn't tell. Her eyes were red, but they were always red. Her frown conveyed worry and caution. Judging from her tense stance, she was taking this rematch seriously.

"Okay, you two," Nico said. "We're going to do this one step at a time. We're just working on form for now. Savannah, don't forget to breathe. Concentrate on Arielle's blade and watch where she puts her feet."

She nodded. "I can do that."

"Perfect. Arielle, nothing fancy. Just strike, parry, strike, parry."

"Yes," the empousa said tightly.

Savannah brought her rudis up into a defensive position, planting her feet slightly apart.

"Starting slowly with Arielle," Nico said. "Savannah, just block her swings. Don't think too hard about it or worry about how you look, okay?"

She nodded. "Got it."

"Begin," Nico commanded.

They exchanged strikes, almost in slow motion. Savannah seemed to get the hang of it quickly. She pivoted to block, then swung from the opposite side. They picked up speed, got a rhythm going.

"Not bad," Nico said, slowly circling the two. "One of the great things about being a demigod is that we have an innate ability to focus our attention when we need to. It's not always perfect, though, so we need to practice honing it."

They picked up the pace some more, pride swelling in Nico's chest as Savannah managed to parry every one of Arielle's attacks.

"And stop!" Nico grinned. "See? You're a natural, Savannah."

She lowered her sword. "I'm sorry for being so dramatic yesterday."

She directed the apology at Nico, avoiding Arielle's gaze.

"You have nothing to be sorry about," he said. "Especially with me. We all get scared and overwhelmed, even after years of experience."

Savannah frowned, apparently finding that hard to believe.

"You did well, demigod," Arielle said.

It was an innocuous comment, said with respect, but Savannah's face drained of color. She made the mistake of locking eyes with Arielle.

Then, to Nico's horror, Savannah screamed and charged.

Savannah swung down—hard—at Arielle's head. The empousa barely managed to evade the strike.

"What are you doing?" Arielle yelled.

Savannah didn't answer. She pulled back the blade, gripping it with both hands like a baseball bat, and swung again.

This time, Arielle wasn't fast enough. Savannah's wooden blade smacked her across the arm so hard it broke the skin. Arielle's flaming hair roared higher, like someone had thrown gasoline on it.

"Stop that!" yelled the empousa. "Leave me alone!"

Nico jumped between them. "Savannah! Drop the sword!"

Savannah's face twisted into a mask of rage. She threw her sword aside in disgust, then screamed again like she wanted the entire world to hear her. "It's her fault!" Savannah howled. "She did it!"

"I did nothing!" Arielle shot back.

Savannah rushed forward. Nico blocked her path, but Savannah's strength surprised him. She tackled him, and they both crashed into the ground.

Savannah rolled off him. She drew in her knees and then let loose a terrible sob. "She did it," she said again. "She killed my parents!"

The whole world seemed to drop out from under Nico, taking his heart along with it. He struggled to his feet and looked at Arielle, who was wideeyed with disbelief.

"What?" the empousa asked, cradling her wounded arm. "I don't even know who you are! I haven't killed anyone in a long time!"

"It was you, or your kind." Savannah shivered. The anger was draining out of her body, leaving her listless and defeated. The blankness in her eyes worried Nico even more than her attack.

"My kind?" Arielle demanded. "So now I'm responsible for every empousa? We're all the same?"

"Arielle," Nico warned. "It might be best if you go back to your quarters."

"But, Nico, I didn't—"

"I know. I believe you. But please."

Arielle stomped, cracking the dirt beneath her donkey hoof. "This is why we have to leave." A blood tear trickled down her cheek. "I don't care if they catch me! I don't care if they judge me—it couldn't be worse than the judgment I'm getting right here!"

She turned and marched off toward the mythics' quarters.

Nico filed her comments away for later. He needed to find out what she meant. But at the moment, Savannah's condition was the bigger problem.

He knelt in front of her. As angry as he was with her for unfairly attacking Arielle, this wasn't the moment to scold her. If her parents had been killed by empousai...no wonder Arielle's presence had triggered her.

Her stare was unfocused. He could tell she was far away. He remembered what that felt like. A panic attack could be frightening, but it could also feel like everything was happening to someone else.

"Savannah," he said, "I need you to breathe. In and out, slowly."

He helped bring her back to herself with breathing exercises—the very ones that Mr. D had taught him over the past few months.

Finally, she seemed to regain her composure, but when she raised her eyes to Nico, rage still smoldered in them.

"Why is she allowed to be here?" Savannah asked. "Why are any of them? They ruined my life."

They.

Monsters. All monsters.

Not so long ago, Nico wouldn't have questioned Savannah's statement. Now everything felt a lot more complicated. He thought about what Mr. D had told him—that the job of elder demigods was to help kids like Savannah adjust to their new world. Nico had botched that completely. He felt like he'd failed today worse than Asterion or Orcus or Johan.

Nico swallowed his resentment and guilt. "Let's get you to the infirmary," he said. "Then we'll figure out what to do next, okay?"

He helped her to her feet, and as they walked slowly back toward camp, Nico felt lost.

He had no idea how he was going to fix this.