Nico wished he could remember Italy as a home. His mother had immigrated from here decades ago, and there was nothing familiar about his motherland now. But he tried. He wanted to claim the fresh, grass-scented air, the stunning blue sky, every rock and crag, the peddlers coddling their wares, the string-thin rivulets that decorated the soft green ground.

What's wrong with Camp Half-Blood? wheedled a small voice in his head.

Nothing, Nico assured it. I just want another home to also call home.

"I want to explore Italy."

Shoon's mouth dropped open for a second before she closed it. With her round cheeks, she looked like a fish. "Are you crazy? We're on a quest!"

"You can go ahead without me. But this is important."

Will's gaze softened, understanding. "Want me to come with you?"

"No."

Marcus placed his hands on his hips. "I'm coming, too. This is important for me."

Will's voice hardened. "Me, too." He winced and looked at Marcus. "Sorry. Old habit."

Annabeth looked at the boys in exasperation. "Guys, we're on a time crunch, here. I booked a flight straight to Greece while we were on the Mariposa. Leona and Piper are finding taxis for us right now."

Nico was resolute. "Sorry, Annabeth, but this is important. I'll shadow-travel us to Greece as soon as I'm done."

"Done what?"

Lilian exhaled. "Please, no more secrets." Xe looked at Marcus, who nodded. Nico's eyes narrowed. Xe explained to the others, "Nico wants to lead a quest to Tartarus, where the Primordial Ooze is located. The Ooze is what gives demigods their power but is affected by when we find out we're demigods. It's likely that something with the Ooze is what's been making Marcus act up sometimes."

"And me," Jason added. His face turned as red as the tomatoes that the Spanish locals had thrown around during their streetcar trip to Alicante. "But I trust Nico. I know I'm needed at Greece more than Tartarus."

"No," Percy said, startling them all except Annabeth, who looked concerned. "I didn't mean you, Jason. I'm saying no to this stupid sidequest to Tartarus."

"It's not stupid," Nico retorted.

Will said softly, "It's dangerous."

"You don't have to go."

Percy grabbed Nico by the shoulders. "You shouldn't have to go."

Nico pushed Percy away. The older boy reminded Nico of his own sister, Bianca. He didn't particularly like it. "It makes sense for me to do this. I'm the son of Hades. I'd fare best in Tartarus out of all of us. Besides, I have a plan. We're near Sant'Anna di Stazzema, a village in Tuscany that was the site of a Nazi crime. Over half a thousand villagers and refugees, many of them children, were murdered in a scorched earth scheme. It'll be easy to access Tartarus from there: go in, deal with the Ooze, go out—quick and painless 'cause I can control all the monsters there."

"Nothing is ever 'quick' or 'painless' when it comes to demigod quests. It should be Camp Half-Blood's slogan. Does Camp Half-Blood have a slogan?"

Annabeth stepped up. "I don't want to rush your decision, but we really need to catch that flight. Leona and Piper should be back soon with our rides."

"It's not a rushed decision," Nico assured her. "I've been thinking about it for some time now."

In his periphery, he saw Will's expression change. Nico didn't dare look at him. He didn't want Will joining their quest to Tartarus—even with Nico's powers, the trip was still bound to be dangerous.

Lilian said to Annabeth and Percy, "Would you feel better if a more reasonable person kept these three from certain death by Tartarus monsters or each other? I can go with them."

Annabeth only looked more worried. "A quest with four people? That's—"

"Bad luck," Shoon piped up, though she sounded more excited than worried. Nico guessed she wanted to live vicariously through their experiences. Once they returned to Camp Half-Blood, she'd boast about visiting Tartarus. "Four is the number of death."

Annabeth nodded like a bobblehead. "What she said."

Percy looked at her with fond exasperation. "You don't believe that."

Nico used their moment of distraction to run. He heard Marcus, Will, and Lilian behind him. At the train station, he spoke to the conductor with urgency, making up some emergency or other.

The conductor was unconvinced until Lilian pulled out xyr wallet. As they boarded the train, xe nudged Nico. "I knew you'd need a more reasonable person around."

Nico didn't reply. He sat across from Will, both of them in stony silence as the scenery flew by. Marcus and Lilian kept up the chatter for all four of them. Marcus was nervous about what they'd see in Tartarus, but Lilian kept their spirits up by joking about getting souvenirs and speculating on what colour the Ooze was. "I'd wager a week of camp chores on green."

"I'm thinking red. You know, like danger?"

Nico spoke up. "It's obviously black."

"Have you seen it?"

"No."

Will smiled, offering a temporary truce. "It's most likely yellow, like pus from an infected wound."

Nico, Lilian, and Marcus chorused, "Eww..."

Now Nico figured it was probably poison-purple or sky-blue, just so the universe could mess with all of them.

It was only as the train slowed down outside the village that Nico remembered his conversation with Leona on the Glorious. The moonlight had turned everything silver, but her flame shone bright orange through it all. She'll be so mad I ditched her.

As they got off the train, Nico appraised his companions. He hadn't expected to bring any of them along with him. The little voice in his head schemed to ditch them, too, and sneak into Tartarus on his own, but there'd be hell to pay when he returned. Dealing with Leona and Percy would be bad enough; he didn't want to face Lilian's disappointment or Will's wrath, too. I'll protect them.

He changed that thought when Lilian stopped Marcus from walking into the path of a running deer. We'll protect each other.

Sant'Anna had a different atmosphere from Livorno. Without the aroma of salt or fresh fish, the petrichor was stronger. Warmth from the soil combatted cold from the stone. Nico genuflected at the ossuary and placed a hand on the stone, which spread its warmth across his palm. Many had died here, but he found consolation in the peace their souls had eventually found.

Lilian pointed at the village church. "Souvenirs."

"Later," Nico promised xem.

Before he could back down or sneak away from the others, he opened a hole beneath them and plunged them all to the depths of Tartarus.