1) Tholrist (the big bad evil guy) has some pretty big problems in his spell selection:
- Rage and Aid are Mind-affecting and thus cannot target undead (him and his allies)
- Command is language dependant and he doesn't speak any languages that anyone in a normal party speaks so he can't do anything with it
Maybe the plan is to have him waste 3 rounds casting useless spells but that's not really implied in his Tactics.
2) His AC is over the top for a party in the lower part of the tier. He's supposed to be up to AC26 with either Protection from Good or Shield of Faith. That's in the CR10-11 range. Couple that with +10 to hit for his 3 attacks that cause paralysis and this guy is a melee killer.
3) That leaves his tactics and morale. He is supposed to ignore paralyzed foes and is unable to leave the room. This means that if he doesn't kill the party right away and they manage to escape to heal up, they can keep coming back, attack him from ranged until they roll enough 20's to pierce his AC and cover (which is everywhere). It takes a while for the PCs to figure this out but when they do, it's dull, dull, dull.
I'm guessing 30 rounds of combat to kill him off unless you have a heavily optimized party with people who can spam ranged touch attacks.
