The patch for NWN apparently breaks it. It causes monsters to stop using any of their special abilities, spells, etc. other than melee attacks. Here’s a post by Bioware’s Dave Gaider from the offical forums:
Ok, I think that’s all the information we need. We have already confirmed that this is, indeed, the case.
I can’t believe some people have gone through the entire game thinking that this was the intended state of things. Gah.
At any rate, know that we consider this to be a top priority to fix (as well as the DM faction/PvP problem mentioned a few posts back).
Yeah, I’ve heard about that DM faction bug, too, but have been completely unable to replicate it. Apparently what happens (or is supposed to happen) is that when you possess a hostile creature, other hostiles start to attack you. So if you have a group of goblins and you posses the Head Goblin, the rest will turn on you. Of course that would be pretty lame.
But in practice, I’ve never seen that happen. I’ve done a lot of playing around with possessing stuff in the DM client, and it all seems to work as advertsied, at least for me. Weird.
I’ve noticed a lot of spellcasters along the way calling down flamestrikes and whatnot on me. But I also fought a green dragon last night, which did no damage to me at all, never used its breath weapon, and never cast any spells.
Now I’m not sure whether to keep playing or put NWN on hold until the next patch comes out…