Board Thread:Questions and Answers/@comment-2135510-20130608053251/@comment-25223616-20140727055820

I have wondered about Tosen's as well, however Yumichika and Oko don't so much as have 2 but have levels to there shikai, like power boost. As for Tosen's, we may never know as he is dead, however, perhaps this is something Aizen did to him, similar to him having a visord mask and a Resurrection. Admittled, that's a little flimsy as Aizen didn't seemingly have the means to do this, but it's a thought.