Sōkyoku

The Sōkyoku is a large halberd, which Taisinkoha uses at Sōkyoku Hill to execute other ninja who have proven to have caused a large crime in the ninja world, such as a murder of a feudal lord or kage. When released, it takes the form of a Phoenix-like entity. As noted by Toshiru, it is a punishment usually reserved for Captain-level Ninjas that have severely broken the law. The Sōkyoku is said to be as strong as 1 million zanpakutōs, and it evaporates the soul of the one being executed by it.

This was later given to Seireitou Hyuga, as a sign of trust between him and Taisinkoha after he helped drive off Akatsuki. When seireitou takes possession, his large spiritual power was able to suppress the blade into nothing more then a katana, which seireitou keeps in the Kitsune Realm and is noted not to really use it.