Engrave your helm with the Advanced Warding rune: Increases the magnitude of your Mana Shield, Frost Ward, and Fire Ward by 100%, and decreases mana drained by Mana Shield by 50% per damage done.
Rune Guide Lvl Slot Zone Advanced Warding Rune Head Felwood Hinterlands Razorfen Downs Zul-Farrak, Maraudon, Blackrock Depths Deep Freeze Rune ...