So, anyone have any ideas what spell Durkon is casting here? It's not straight up Control Weather — that spell can't do damage... None of the Call Lightningvariants can do sonic damage... And besides, those are druid spells. Sound Burst is way too weak to account for the damage we're lookin' at there.
We haven't seen any feats or spells from expansion books, yet; we have reason to believe Burlew is sticking to materials from the SRD. So no Energy Substitution feat (it was off a scroll, anyway...)