Board Thread:Naruto Discussions/@comment-24847491-20140920090914/@comment-28861328-20140920173606

JOA20 wrote: ItachiWasAHero wrote: This does make sense. It seems far more likely and didn't Tobirama say something that hinted this? Tobirama commented on seeing Kagutsuchi before Sasuke showed him. So one between Madara and Izuna had Blaze Release as well.

Or, you know, any of the hundreds of Uchiha clan members alive in Tobirama's time.