“Seeing them assembled in Tartarus, Percy felt as hopeless as the spirits in the River Cocytus. So what if he was a hero? So what if he did something brave? Evil was always here, regenerating, bubbling under the surface. Percy was no more than a minor annoyance to these immortal beings. They just had to outwait him. Someday, Percy's sons or daughters might have to face them all over again.”