Board Thread:General Discussion/@comment-24065031-20131018111356/@comment-11051098-20131021152434

As far as I understood before, Kyôraku's Zanpakutô only has 1 spirit, Katen Kyôkotsu, although it might be split into 2 manifestations, hence the 2 blades.

It was shown to be 2 spirits, but that was in the anime filler arc with the Zanpakutô rebellion.