It's impossible to survive this without serious fire protection. Use items which give you that. I had only Imoen unprotected and she prepared a CC, enenmy sighted, target self stonskin, promw, prot energy. My figh/mage had elemental robe so he's ok, and I dressed cler in great wyrm. move Immy and cler away from battle, use fighters to kill those guys (death lords I believe) first because they drain thac0 and use ww and critical strike (I think they have that +4 2hswrd soul reaver). Alone they're pathetic by this time, but with others in this battle they are devestating. CC from imoen (remove magic, 2x ADHW) also works great on them. after they're gone (Demon lord will call for more, so concentrate on them first. they don't use pfmw I think). Next I did elemental golems because of high damage output and ability to summon golems. I left those small golems to Imoen with hand of undoing, 3xray of frag in sequencer also does wonders. Immy can also deal high damage to elemental golems with those spells, much more than fighters. but keep her away from demon lord or he'll kill her very fast. improved alcatry, robe of vecna are also very beneficial. Use wish spell to refresh fighter hla's (hardiness is not an option, but a MUST). Rang-cler did a lot of greater restoration. Always watch where demon lord is. It's great if he attacks the guy wielding JD sword, because it gives the others room to breath. It's hard to keep your guys together here, they tend to get seperated. Hope everybody is a powerhouse by himself:). Try making demon lord do battle with Minsc, in your case. Minsc shouldn't be attacking him, but a target who doesn't use pfmw so you can get wish and other benefits of JD (hope you gave Minsc 18 wis). My figh/mage was useless vs.demon lord, he kills your protections asap, but those golems don't, so I used him against them. Have prot vs poison items or scrolls when fighting marilyths. Concencrate on one at the time, they regenerate fast. they cast pfmw, so switch target when that happens, or use remove magic. Breach may also work on them. The battle may seem overwhelming, but the number of enemies is not "unlimited". I used my figh/mage to "collect" golems around him, and then used stoneskin and mirror image for defence. They attack slow, so it lasts for a while. I believe you can't breach demon lord. Maybe a remove magic would do, depending on your level, but for me it didn't. when he was left alone I attacked him with my protag only who had 85 damage resistance (hardiness, flail, armor and JD) until his protections expired. he has a lot of pfmws so it takes a while. When he's done casting pfmw, swarm him with fighters. Use Gww if you're wielding 2-h weapon, much better than imp.haste.