Board Thread:Speculation House/@comment-108.180.145.133-20130922140854/@comment-9219983-20130924050427

if you pay attention to the intro, it is heavily implied that Grimm creatures existed before man...

About the Grimm creatures "bleeding" smoke, could be just a style method for not using blood, and thus, make the show acceptable for younger audiences... we have seen this in many games, where they use something instead of blood, in order to make the game T instead of M...