Andariel Quest Bug D2R. Andariel, act i's end boss, drops better loot every time you kill her for the first time on every difficulty (this applies to all end bosses). However, it is the only item in the game that carries a penalty to a resistance, specifically, fire, which is consistent with andariel's actual vulnerability to fire.
If you have magic find and gear that can improve up to about 300% better. If you don't know about andy quest bug,. The andariel bug has been fixed (i’ve only been able to test this in sp).