HBO have released a teaser trailer for season 6 of Game of Thrones which gives little away but does leave the Jon Snow sage very much in play.  Also, after a season on the bench, Bran Stark looks ready for a return to action and seems to be very much in-tune with his supernatural gifts.  Max Von Sydow, from The Exorcist, can heard and will apparently be taking the vital role of the three-eyed raven that assists Bran in using his powers, while the white walkers look to be an even more menacing presence in season 6 which will be released in April.