Board Thread:Warhammer 40k General Discussion/@comment-28383085-20170330013226/@comment-25177957-20170330234935

@MorkarBaroque, if you read the renown 40k fanfic "Shape of the Nightmare to Come" (google it), there is eventually a corrupted version of Grey Knights known as the "Blasphematti" created by Abaddon sometime around 50k. I won't spoil anymore about the story though.