I thought the point of magical and physical armor was precisely to avoid such scenarii?
If you try to protect vs one you lose to the other, if you try to protect from both they blow through your defense and still hit you. You dont know who does what until they do it and most of the time they do both. Also with the initiative issue they always go first and when you go, you dont get to burn through their defenses. So they essentially get to go twice on your defense bars while doing a lot of damage, especially in classic mode. Playing a mage in classic mode means if you get targeted you are guaranteed to get cc'd heavily.
