Board Thread:Theories and Speculation/@comment-26119997-20150219181955/@comment-25549954-20150219194809

Probably the side effects of the fruit, and also pride was consuming her, now it makes sense that she wanted all chakra and so she merged with the Shinju on purpose. But what makes little sense is that Black Zetsu mentioning an army that doesn't have anything to do with the plot, why not just say they will turn into White Zetsu. Something that doesn't make sense probably has some side story.