The Black Blade is many centuries old and possesses a variety of mystical properties that it possesses in and of itself and properties that it grants to those who wield it. Muramasa took a portion of his soul and used it in forging the sword. As a result, the blade also contains a portion of Muramasa’s evil and madness. The alloy that the sword is made of is unknown and is black in color, but has shown to be virtually indestructible. The blade also grants superhuman physical strength and resistance to injury to whoever wields the sword. However, eventually, the madness and evil that Muramasa poured into the blade will eventually overcome the will and original personality of an individual if he or she has it for too long.