I know of plenty of creatures with certain elemental immunities, but none with a weakness, or at least noticable. If there are ones with a noticable weakness how does it factor in? Greater damage potential?
Ifn i remember right Water Spells seem to work real well on atik'ets and Electricity Spells similar on Frostweavers. Nippu Oshu's are extremely susceptable to Frostbite. Would be an interesting lil quest to track em all down.
Rehlyn
The strongbox just bounced out of the room near a low tunnel!
I suspect barghests are weak to fire, I have one-shot hulking bargs with a min prep FB and AP Damage, 270ish PM, I might get a stun 75% of the time with a 10 mana GZ, and no one-shot kills that I can recall.