Twins in mythology upon. However, other cultures attribute the outcome of twins to superior virility of the father. In various mythologies, twins often represent the dualistic nature of the universe. In Greek mythology, twins Apollo and Artemis, are the sun god and moon goddess, respectively. Similar forms of higher beings are reflected throughout different mythologies, as twin brothers Kuat and Iae represent the sun and moon in the Xingu mythology of Brazil. Egyptian God, Geb, and his twin sister, Nut, represented the binary nature of the world, with Geb being the God of the Earth, and Nut being the Goddess of the sky.
The Trials of Apollo own robots. They then navigate the maze with the help of Piper McLean and Jason Grace and find defeat Medea, the sorceress who was working with the emperor. Around this time Caligula (the emperor) kills Jason Grace. The next day, Grover, Meg and Apollo using Caligula's shoes walk the Labyrinth. They free Herophile and discover a new prophecy: “Apollo faces death in Tarquin’s tomb unless the doorway to the soundless god is opened by...”. They also discover that they need help from ‘Bellona’s daughter’, Reyna, the praetor of camp Jupiter. "The Tyrant's Tomb" is the fourth book in the series.