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
God of War III kills Hera, ending all Greek plant life, and makes his way to the Labyrinth to find Pandora. The imprisoned architect Daedalus tells Kratos to unite the Labyrinth. Completing this task, Kratos fights his way through the aerial puzzle and rescues Pandora, who tells him to break the Chain of Balance so the Labyrinth can be raised, and she can reach her box. Neutralizing the three judges and breaking the chain, Kratos raises the Labyrinth, and Pandora tries to enter the Flame of Olympus. Zeus intervenes and fights Kratos; after a brief battle, Pandora sacrifices herself and quenches the flame, despite