We weren't altogether surprised when 'Supernatural' revealed Misha Collins would again be returning in season 10 as series regular Castiel, but it seems the decade milestone will also see Castiel's other side of the coin finally given his due. After four seasons, Mark Sheppard's demonic Crowley will ascend to series regular status, with an understandably meaty part for the King of Hell in season 10.

You're warned of spoilers for 'Supernatural' season 9 finale "Do You Believe in Miracles" from here on out, but the promotion falls perfectly in line with the shocking final moments of this past week's closer, wherein Dean (Jensen Ackles) awoke from death with the black eyes of a demon. The character had died from wound's sustained in battle with Metatron (Curtis Armstrong), though Dean's "Mark of Cain" and the "First Blade" refused to let go of its murderous host, and triggered the transformation.

For his part, Sheppard had first appeared as Crowley in season 5, recurring throughout the years as he ascended the ranks from Crossroads Demon to current King of Hell. Season 9 in particular saw a meaty part for the former 'Firefly' star, as Crowley found himself with an addiction to human blood, and grew his relationship with Dean in order to combat the villainous Abaddon (Alaina Huffman).

It remains to be seen what will come of 'Supernatural''s tenth season, now that the CW has committed to developing another spinoff to replace the failed 'Bloodlines,' but what say you? Are you happy to have Crowley promoted to full time for season 10, or might it be a sign of the end? Give us your 'Supernatural' season 10 predictions in the comments!