How HBO foreshadows. The mountain is brought back to life at the end of season 5 by Qyburn. Melisandre flees back to the wall for what reason? Simple... To bring Jon back to life. She saw what she saw in the flames, but it is never 100% accurate. (As told in previois season) She need to used R'hllor's power to bring the true king back to life and make it happen.