Honjo Masamune was created by the legendary sword-smith Gorō Nyūdō Masamune in ancient Japan. It possesses special abilities.
Masamune cannot be unleashed unless the wielder is pure of heart and says the incantation ‘Honjo Masamune, cut my enemies down!'.
When wielded, the sword is actually extremely sharp and has been seen cutting through steel without problems. It could also shoot energy beams from the tip of the sword.
It could also possess other powers, depending on the wielder.