Anti-Christ Series

The Anti-Christ Series is a Fanfiction Series starting as early as during Season 4 where it is revealed that John Winchester was possessed twice by a Demon when he impregnated Mary Campbell Winchester, due to this Dean and Sam are revealed to be dormant "Anti-Christs" and later it is revealed that they are "Pure Anti-Christs" due to Lucifer's essence breaking free of the Demon hence killing it after the second time, it is revealed that both Heaven and Hell want to use the Brothers as Key Weapons against the other.