The unnamed bronze mirror-shield (青銅鏡の盾, ?) of Perseus is one of the five Noble Phantasms granted to him by the Greek gods for the purpose of slaying Medusa. Granted by Athena, it is a bronze shield polished to bear a mirror-like reflection. Acting like a sort of detector that possesses sonar and radar functionality, it reflects the surroundings onto itself, showing the layout of an area and the heartbeats of any life present in the location. Unlike how it is recorded in legend, he did not reflect Medusa's petrifying eyes back at her, but instead focused only on the projected information to find her location and battle her while avoiding having to look upon her.