Board Thread:General Discussion/@comment-1351982-20130515183016/@comment-4469678-20130527140429

I don't know, Mayuri blamed Yamamoto for his failure to kill Ywatch. It seems more likely that Yama could have killed him, wanted to kill him, but failed to. Maybe he hesitated and gave Ywatch a chance to live, maybe he allowed him to live because he felt saddened by all the death (we've already seen that Yamamoto referred to his past self as a monster). Or maybe he blamed himself for the war and let Ywatch live as atonement?