R'hllor, the heart of fire, a deity worshipped primarily in Essos but gaining followers in Westeros through the red priestess Melisandre. The faith sees the world as a battlefield between R'hllor (light, heat, life) and the Great Other (darkness, cold, death). Red priests can perform genuine magic - seeing visions in flames, raising the dead, and creating shadow assassins. Melisandre attaches herself to Stannis Baratheon, believing him to be Azor Ahai reborn.