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
Daedalian Opus to the player. At the final level, the player is given the 2x2 square O tetromino and must complete an 8x8 square puzzle. After completing each level, the player was given a password to access that level at a later time. Each password was a common English four-letter word, so that by guessing common four-letter words, players could potentially access levels they had not actually reached by playing the game. The name of the game was inspired by Daedalus, the mythical character of Greek legend who created the labyrinth. A faithful fan version was later coded for the MSX computer