Geyser : Quite possibly no resistance, it definately shouldn't be cold, and I don't think fire - just the impact / turbulence of water causing damage.
Sulphur Haze : Definately does poison damage.
Vine Arrow : Does damage _and_ entangles, if it hits.
Acid spells : No resistance that I know of, but I might be surprised.
Gifts from Heaven : I think that's huge whopping impact damage, so no resistance, but if you have 150 armor protection...
Farstrike : Not sure if there's a ToHit resolution as per a melee attack, but it always has the possibility of hitting an empty square altogether.