A/N: Hi all! Thanks so much to everyone who read and reviewed the last chapter. I was going to wait to post this one until I had the next one written, but I was taking too long to finish the next one, and you guys deserved a chapter sooner than later, so here this one is! It's a little on the short side, but I'm hoping to finish the next chapter in the next few days, so it should be up in a week or so. I hope you all like this chapter, and please let me know what you think in a review!

Disclaimer: I don't own PJO. I do own my OCs.

It was a manticore, because Nico's life was unfair. He wasn't sure if it was the same one Percy had fought back at Westover Hall all those years ago— this one didn't try to taunt or threaten him in a vaguely French accent like Dr. Thorn had done, so there was really no way to tell— but it was just as formidable. Between the three of them, Nico, Percy, and Jeannine were able to hold back the monster without sustaining any injuries. It was hard work; there might have been a time when Percy and Nico could fight seamlessly next to each other, each anticipating the other's moves and building off each other's energy and fighting styles.

But that had been fifteen years ago. Now Percy was taller, broader, and out of practice. They were both distracted, thinking of Adrianne and a very pregnant Annabeth only a few yards away. And in addition to all that, Nico had to keep calling out warnings and advice to the very inexperienced Jeannine. He was almost starting to regret insisting she come along, when Jeannine suddenly hefted the bronze sword and swung it in a wide arc, neatly severing the manticore's scorpion tail from the rest of its body. The monster screamed and exploded into dust.

Nico didn't have time to congratulate his sister. He barely even had time to breathe. The manticore had broken a hole through what was once Percy's front door; now a hellhound the size of a truck appeared in the same hole, flanked by two blood red harpies whacking the ceiling tiles with their wings.

Percy let out a string of curses that Nico had definitely never heard him use at sixteen. Jeannine's eyes widened with the same paralyzing fear he'd seen in her earlier. Nico opened his mouth to tell her to go back and hide with the others, but then she lifted her sword a bit higher, her expression hardening with demigod determination, and Nico decided if he lived through this day, he was going to have to thank his father for having another kid.

For a while, Nico tried to narrow his focus, not letting himself think of anything else but fighting, keeping his cousin and sister safe. So he almost didn't notice when the bedroom door at the end of the hall creaked slowly open. He didn't notice the footsteps rushing down the hall towards them.

In fact, he only realized that three fighters against the monsters had become four when his sword suddenly went wide and caught against another blade with a bone-jarring clang. Nico froze, eyes wide and sword gripped tight, and found himself staring into Adrianne's bold brown eyes.

"Adrianne?" he exclaimed in shock before twisting out of instinct and slicing through the harpy that had been trying to sneak up on him. "What are you doing here? I—" He stabbed his sword into the hellhound's flank just as Percy came in from the other side, making the monster howl and bleed golden sand. "—I told you to stay with Annabeth!"

"I wanted to help!" he heard his sister shout amid the racket of blades and inhuman roars. "Annabeth gave me her knife."

Nico tried not to let the panic that that statement filled him with distract him from the task at hand. He moved like a whirlwind, slipping in and out of the shadows, kicking off Percy's apartment walls to leap onto the hellhound's back. It was harder than it should've been, two to four children of the Big Three against three— now two— enemies. But neither Percy nor Nico was as proficient at this as they once were, and Jeannine and Adrianne weren't trained at all. Jeannine was fighting with a too-big sword, Adrianne with a too-small dagger, and they were all trying to navigate the narrow space of Percy's front hallway without risking stabbing each other instead of the monsters.

As soon as the harpies and hellhound exploded into dust, they were replaced by one monster after another, appearing seemingly out of thin air in the foyer of the apartment. Nico wished he could raise some skeletons to give them a hand, but he didn't think he'd be able to call souls out of the Underworld on the fifth floor, and he didn't have time to waste by trying if it didn't work.

He could feel himself growing tired as he slashed and stabbed— some of the monsters had even managed to get a few hits past his guard, and he was dimly aware of blood painting his skin from some claw marks on his left arm— but he couldn't afford to slip up. It wasn't just about keeping himself alive and safe at this point. He had to protect his sisters, his cousins, and their unborn child.

A fresh wave of adrenaline gave Nico new strength. "There's too many of us in too little space," he shouted to his sisters as Adrianne narrowly escaped being swiped by Jeannine's sword. "Both of you hang back and try to cut down anything that makes it past us, keep them away from Annabeth. Percy and I will take care of the rest."

Jeannine and Adrianne both nodded, looking relieved, and retreated to guard Annabeth's bedroom door. With more space to move and less reason to worry about the girls, Nico instantly relaxed before rushing back into the fray.

"We really shouldn't have been surprised," Percy commented almost casually after another minute or so of fighting. "This many powerful demigods in one place; we were almost asking for an attack."

"Yeah, but we still don't know why they haven't attacked before now," Nico pointed out. That wasn't the only thing they didn't know, but he'd been serious about not letting Percy get dragged into this more than he had to.

The first step in that, of course, was making sure Percy didn't die here and now, so it wasn't like they had a whole lot of time to chat.

The fight went on for who knew how long. As soon as Percy or Nico turned one monster to dust, another would take its place. Nico felt exhausted and in pain, and he started to think desperately that if this didn't end soon, he wasn't sure how much longer he could go on.

Then, suddenly, a weird hybrid cross between a tiger and a crocodile got through Nico's defenses and knocked him to the ground, his head slamming painfully against the floor and his sword flying out of his grip. Nico tried to raise his hands to defend himself, but the monster had already moved past him, stalking towards his sisters at the end of the hall.

The monster growled low in its throat and bent its front legs as if to pounce. Jeannine and Adrianne dutifully raised their weapons, but somehow Nico knew it wouldn't be enough.

"Bianca!" he shouted, trying to push himself to his feet despite the ringing in his ears.

And then he heard a series of sounds he hadn't heard since he was ten years old and would've been entirely content to never hear again: the baying of wolves. The shrill pierce of a hunting whistle. And then a wind-torn shriek as arrows sprouted from each monster's neck, and their enemies instantly exploded into dust.

Nico turned toward the makeshift doorway and stared, certain he must be hallucinating.

"Good to see you, cuz," said Thalia Grace, looking all of sixteen and holding her signature bow. "It's been a while."

A/N: Hope you liked this! Please review, and I'll try to get the next chapter up as soon as possible!