Board Thread:General Discussion/@comment-24489167-20150328154801/@comment-26066301-20150410231131

JaneDoe001 wrote: As much as a surprise twist (my idea twist anyway) that Shredder uses the formula on Splinter to have him destroy his own family (hey come on, Rat King did it) would be shocking, as would it be that Shredder uses the turtles to target Splinter, I believe Donetello's theory of using in on all of the citizens of New York to be the most accurate.

jD001 True, and the fact that Shredder is using a factory to mass produce one of the ingredients also supports that.