Hmmm I can't remember accurately (so maybe I shouldn't be saying anything at all haha) but I seem to remember different AOE attacks reacting differently to lightning shield. I think I remember mage blizzard not procing it (I know it goes against what the other poster said, but it's what I remember) but I remember if he Arcane Exp. me it did proc it. So different AOE attacks might behave differently. Head to the STV arena and try them out!