Board Thread:Episode Discussions/@comment-25319479-20160407114523/@comment-26937472-20160408230721

Sarutobii2 wrote: Zabuza became a member of the Seven Ninja Swordsmen before his attempt assassination on Yagura.

So if Juzu, who is in possession of the Kubikiribocho kills off Yagura, Zabuza can't get a opportunity to assassinate him while being a member of the Seven Ninja Swordsmen, since Yagura's already dead. Looks more like Yagura killed off Juzo. Bijuudama and then we see Kubikirihocho on the ground.