Kill the Demon of the freaky Cult

How do you kill the Demon and keep him down, I have on a number of occasions had him read "Death" and he melts into the floor and reappears. How do you drop him and keep him down.

kill all the cult guys... then he should only reapear once...

BTW, what do you guys think about that guy. he was hard, but not deserving of the position of main boss of a fine expansion... especially considering he was in the basement of the house next door
!!1

I don't know that it bothered me. I guess since I played through Baldur's Gate with the expansion the first time, I just kind of viewed this as a side quest, part of the adventure, but not really a boss that was ending a chapter in the PC's quest. I liked the story telling of getting all the way through Durlag's Tower, only to have to return to the village to put things to an end.

that's what i thought they were getting at, and it would ahve sort of worked if not for the way that dwarf in the inn brushed you off like you did nothing at all. [unexitedly] he said something like" you've killed him for now he'll come back, you're a hero," and he walks out. black isle should ahve accounted for the fact that most people by the time they fight the guy are maxed out in xp, and any new weapons or items they get could only be used to do maybe 6 side quests that were not done, and the final battle with sarevok (since you lose all items upon starting gate2). this means they should have added more gameplay, and i see what they were getting at, and maybe if i viewed it as one quest it would ahve worked, but as soon as the cult guards attacked me, it became a whole new quest, a continuation, and then it turned out to be the shortest quest i can remember.