A secret sword with an incredibly long blade. While the truth is unknown, it is described in a variety of legends. One famous lore says that the sword grants power and luck to those who have sworn revenge. Its edge is unusually sharp and as befitting the legend, it clouds and enrages the mind of its wielder.
When loosely translated into English, Kagekiyo comes to mean "Pure Shadow".
This sword is most likely named after Taira no Kagekiyo, the protagonist of the Namco arcade game Genpei Tōma Den (The Genji and Heike Clans), in which a resurrected Kagekiyo returns from Hell to seek revenge against Minamoto no Yoritomo and the Genji Clan.