User blog comment:Godisme/The Buckbeard/@comment-4469678-20120308040020/@comment-4515326-20120308044624

its possible that sasakibe watched as the bad dudes took a bankai from one of the captains, but i'd say big yama would have already found out that the vandrenreich were there if there'd already been a fight. maybe they have bankai's off of previous captains or something, but speculation probably won't get us anywhere when we're dealing with Kubo