Hi,
I've managed to kill Irenicus, but not before losing one character entirely and the inventory of two others. Is there a possibility to kill him fast and leaving my party intact (I'd hate to lose all those nice artifacts)?

??
are you talking about the endgame in hell? Or right before it in suldanessalar? Or in the asylum??

WEll i'm an idiot. It said "before hell". I THINK you mean in suldanasselar. Well, all i did was cast time stop from a scroll, then abi-dalzim's horridwilting twice, then i a quickly let loose a spell sequencer which had 3 fireballs. Hope this helps.