What really bugs me about mug, is that the tooltip doesn't specify that it has a "chance" to mug items from an enemy. All its says is that it increases the amount of items dropped by an enemy. I feel like it should actually say "It increases the chance that enemy will drop additional loot" or something so its less confusing. In the last 35 levels, I have only seen MUG work once, and yes, before you ask, Ive been using it as the killing blow.