As for Piper, all she could do was stare at her knife Katoptris, trying to locate Leo, Hazel, and Frank. The only images that came to her were ones she didn’t want to see: three black SUVs driving north from Charleston, packed with Roman demigods, Reyna sitting at the wheel of the lead car. Giant eagles escorted them from above. Every so often, glowing purple spirits in ghostly chariots appeared out of the countryside and fell in behind them, thundering up I-95 toward New York and Camp Half-Blood.
Piper concentrated harder. She saw the nightmarish images she had seen before: the human-headed bull rising from the water, then the dark well-shaped room filling with black water as Jason, Percy, and she struggled to stay afloat.
She sheathed Katoptris, wondering how Helen of Troy had stayed sane during the Trojan War, if this blade had been her only source of news. Then she remembered that everyone around Helen had been slaughtered by the invading Greek army. Maybe she hadn’t stayed sane.

The Mark of Athena, Chapter XXV