As Thanee said, Iron will.
Seriously, You'll have good Fort Save for those death effects (and really, how many spellcasters target their fingers of death at the greataxe wielding , mouth frothing maniac instead of the wimpy dude with the pointy hat?). You have a s****load of HP for those pesky Ref saves. Be a barbarian, suck up that fireball

. But will saves are your Achilles heel. What wizard doesn't start foaming at the mouth at the simple though of dominating that same maniac into pounding his buddies into mush.