>>715786040
The spell does raw magic damage, not physical (as an exploding skull would suggest), fire or lightning, so it bypasses every defense bar magic resistance and saving throws. It gets so ridiculously powerful there's basically no reason not to take it. Skeleton Warriors and Bone Golems are immune as I recall, and Drow will stand up to it pretty well, but it will just delete everything else.
>>715786160
It doesn't bypass magic resistance, it just does that much damage, and not many enemies have magic resistance high enough to matter against it. It might have been different for BG1 though, not sure.
I think Flame Arrow does piercing and fire, so magic resistance doesn't come into play.
