I Want To Believe
They were doing this before the time of Noah, (read the books of Enoch and Jasher) and that is why the Creator sent the great flood, because "their" intent was to corrupt all flesh, so as to prevent His Son from entering the world to restore what was being corrupted, namely our souls, but also our flesh. Messiah was to come through a certain blood line, and if that blood line could have been cut off, all would have been lost... hell would forever reign on earth. It is said that a chimera is a soulless creature, a perfect shell for a spirit being to inhabit... why else would they be abducting humans and performing sexual probings and manipulations, why else do they mutilate cattle with laser like precision, why else do the little grays appear soulless and without emotion. Perhaps the grays are the source of the mythological Imp.
I believe, in the evils work of Satan and the Redeeming work of the Messiah and one day, perhaps sooner than we think, Messiah will seal our redemption, those of us that believe, and will destroy the works of Satan and his minions!