Back in April, we reported on an upcoming Hellraiser HBO television series coming from genre luminaries like David Gordon Green and Danny McBride (Halloween), Michael Dougherty (Trick r' Treat), Mark Verheiden (Battlestar Galactica), and Roy Lee (It). Conspicuously absent from this list? Clive Barker, the original creator of the mythology that's spawned an iconic horror multimedia franchise. But now, per Deadline, Mr. Barker has been dragged back to Hellraiser, joining the HBO take on the material as a new executive producer. [caption id="attachment_786830" align="alignright" width="360"] Image via Entertainment Film Distributors[/caption] Barker is happy to join …