Azamaru

Azamaru was the name of a sword initially held by Taira Kagekiyo. When a later owner, Kageyama Kazukage, was blinded during the Siege of Ôgaki castle in 1547, and the next owner, Niwa Nagahide, began having eye trouble, the sword was believed to be cursed. Nagahide donated the sword to the Atsuta shrine, in order to be freed from the curse. After the donation, his eye troubles went away.