Q is a peasant who casts Finger of Death. The problem is that he has 16000 (yes, sixteen thousand) hit points, so that no matter what you use, he takes a fair bit of killing. The best way to do it is to arrange your party just around a corner from Q, so that you can hit him, and his spells waste themselves on the edge of the wall corner.(I assume you know where Q is! I also assume that you're playing the v1.2 game with Mok's patch — I think this overcomes the bug that slows up characters using dual weapons.)
I'm not absolutely sure, but I think that if you arm your knight with a sword of Darkness and a Vampiric Sword, plus an item of Regeneration, he does very well in battle.
