'Game of Thrones' Launches Challenge to Find Thrones Worldwide To celebrate the hit show's final season, br HBO launched a br "For the Throne" br campaign in br anticipation of br the release. The latest part of that campaign br asks fans to hunt for six Iron Thrones br hidden around the world. The network has revealed a br series of hour-long videosbr to serve as clues. The clips were shot with a br 360 degree camera, allowing hunters br to examine each throne's surroundings. As of now, the only "prize" is the br satisfaction of solving the challenge. Last month, HBO br partnered with the br American Red Cross to br urge blood donations br with their "Bleed for the br Throne" campaign. The final season of br 'Game of Thrones' airs April 14.