Go to the Wall of Argos and hunt monsters until you get the 500 Glimmering Eye of Argos
Target:
Canyon Antelope Slave, Canyon Bandersnatch Slave, Eye of Restrainer, Buffalo Slave, Grendel Slave, Eye of Guide, Gaze of Nightmare, Eye of Watchman, Eye of Pilgrim, Eye of Ruler, Homunculus, Elder Homunculus.