Priests of Sigmar (ie, Warrior Priests and Arch Lectors) can invoke their patron god's protection against the sorcerous powers of the enemy. So long as he is on the battlefield and is not fleeing, a Priest of Sigmar adds a number of dice to the Empire player's dispel dice pool during the enemy's magic phase. A Warrior Priest adds one dice to the dispel dice pool, while an Arch Lector adds two.