Kubikiribōchō (Shadow Rage)

The Kubikiribōchō (首斬り包丁; Literally meaning "Decapitating Carving Knife") is a massive broadsword shaped like a giant butcher knife, passed down from generation to generation amongst the Seven Ninja Swordsmen of the Mist. It has a circle cut out of the top and a semicircle near the handle, which, as demonstrated by Suigetsu Hōzuki, seem to fit the sword's purpose of decapitation aptly, and the latter gives something to wrap a back strap around, in order to carry the weapon. Its extremely long handle is detachable: Suigetsu was shown screwing it off before travelling and reattaching it for combat.

The sword possesses an unique power, this being its ability to reform itself using the iron harvested from its victims' blood. This regenerative process takes place almost instantly, and is capable of bringing the weapon back to its original perfect condition no matter how severe the damage is, from a simple chip or a nick to a completely missing half of the blade.