What does it mean when a shield has +65% enhanced damage? IS this only for smiter or does it stack with some other gear Like auras etc how does it work
same with a helm with 40% enhanced damage what does it exactly mean
There is a damage calculator you can google that will give you the proper calculation, however I will explain it the way I understand and let the experts here correct me if I'm wrong. % ED increases your attack damage based on your base weapon stats. However there is a difference between % ED on a weapon and % ED on non-weapon gear (helm, shield...).
% ED on your weapon will be calculated first to modify your base weapon stats. THEN % ED from non-weapon gear and % ED from any skills will be added up and applied after. So for example if your weapon does 10-20 dmg and has 50% ED then the new base stats will be 15-30 dmg. Then if you have 100% ED from other non-weapon gear and skills, your total attack dmg will be 30-60 dmg.
There are also some cases where your character screen does not properly reflect total damage, particularly with smiter. For example I believe % ED on weapon does not affect smite dmg, but % ED on non-weapon will benefit smite dmg.
It's been a while so I don't fully remember and the calculation is much more complex than that, but hopefully that helps.