How do you defend against the MindFlayer brain suck ability. Ocasionally, when I'm in a brawl with mindflayers (and the mindflayers with other names) members of my party will just drop dead after getting hit with a comment like "Mindflayer ate Minsc's brain".

Yeah, those guys are hard ones to destroy, what i did was to equip my best fighter with a weapon or helm vs charm/domination and had a sword that prevents held spells so he became totally immune to thier long range attacks, the problem was that they sucked his mind dry so he died right away. i figured out that i should give me fighter a potion of (something) that increases his intellect, once that is done, i had an easier time to kill them. done use Minsc to attack cuz he has very little intellect. Hope it works for you as it works for me =)

There is no defense against the mind suck ability as far as I know. Use haste and bless and chant etc. and mix them up hard if you can. If you can't, summon loads of undeads, who are immune to the intelligence drain, and kill 'em at range. Remember to use chaotic commands or something that makes you immune from Domination, or you'll regret it.

I hate the illithid. There really is no trick to killing them; you can protect against their psionic attacks relatively easy, but as if that wasn't enough, they're also deadly when they come into close range. The way they work is this. Each melee hit of theirs drains, I think, five intelligence. If your intelligence drops below zero, you're dead. Simple enough. I had Edwin conjure an invisible stalker, which is immune to their mental attacks and can't be mentally drained (I think it has a null intelligence factor or somesuch).