|Owner:||Gilgamesh, Perseus, Rider (Fate/Prototype)|
|Maximum number of targets:||unknown|
Harpe (ハルペー, Harupei?) is the snake hunter's scythe used by Perseus to kill the Gorgon Medusa. It is described as a monster-killing holy sword that isn't actually an outstanding sword by itself. Its true strength is its trait of "Refraction of Longevity", which is a divine ability that nullifies the special abilities of immortals and inflicts wounds that cannot be restored by any methods other than healing in accordance to the natural laws. It is found within Gilgamesh's Gate of Babylon during Fate/stay night.
It is one of the five Noble Phantasms given to Perseus, the most legendary artifacts given to a single person in Greek history, for his quest to slay Medusa, along with a helmet of invisibility, a mirror shield, the mystical bag, Kibisis, and winged sandals capable of flight. Both Harpe and sandals were given to Perseus by Hermes, and the shield was given by Athena. The mirror shield is a bronze shield polished to bear a mirror-like reflection that projects information from the surrounding environment on its surface so the user can rely on that information to move around without having to move himself away from the mirror. It can also be used as a sort of detection device as it transmits the heartbeats of those in the area. It was unable to reflect Medusa's Mystic Eyes like in the legends, so he instead focused only on the projected information to find her location and avoid having to look upon her. The sandals were quick enough to allow him to avoid her strikes for a long period of time. Kibisis (キビシス, ?) is a anti-sealing Noble Phantasm that distorts the concept of the world, placing the inside of the pouch on the outside and the outside of the pouch on the inside. It inflated and swallowed Perseus, creating a fold in space that placed the outside world into the inside of the bag, and Breaker Gorgon, which affects only what is inside, was reflected back, making Medusa look upon herself as if reflected in a mirror, allowing him to slay her with Harpe while she was immobilized.