The Antikythera is a complex construct that acts as a magical compass. It also has the power to mend damage to a ship: once per day it can magically repair 50 hit points of damage to a ship it is aboard. It uses the constellations to guide its user to islands in the Cerulean Gulf or Forgotten Sea. Every island in these seas are associated with a specific constellation. The Antikythera must be used on dry land as the constant movement of waves makes it impossible to calibrate. When it is calibrated to the proper constellations, it will show a path that can be used to reach the island associated with a particular constellation.