The Battle of the Labyrinth camp for the school year. On his fifteenth birthday at the summer's end, Percy receives a visit from his father Poseidon, who gives him a sand dollar, admonishing him to “spend it wisely”. Nico later appears to tell Percy his plan to defeat Luke once and for all. "The Battle of the Labyrinth" was initially referred to as "Percy 4" until the title was officially revealed. The novel was teased by Rick Riordan behind the pages of its predecessor, "The Titan's Curse". It was based on the Greek myth of the labyrinth, where the Minotaur was supposedly kept. In his
Daedalus Minos kept it for himself; and in revenge, Poseidon, with the help of Aphrodite, made Pasiphaë, King Minos's wife, lust for the bull. For Pasiphaë, as Greek mythologers interpreted it, Daedalus also built a wooden cow so she could mate with the bull, for the Greeks imagined the Minoan bull of the sun to be an actual, earthly bull, the slaying of which later required a heroic effort by Theseus. This story thus encourages others to consider the long-term consequences of their own inventions with great care, lest those inventions do more harm than good. As in the tale of