Ok, heres how it is. To protect myself from the demilich(the lil floating skull) i used spell immunity: abjuration (bet ya didnt think of that) on my mage. To kill the skull i tried melfs minute meteors on it, it did the damage but every time i got him injured he would just go back down to barely injured again. the meteors take only 1 hp off each hit so my question is this, is it just a bug that he keeps going back to barely injured or do i need a better weapon to kick this guys ass?????

Well i'll won't spoile u, but he has a regenerating ring on. Cool ring!!!!

After I killed the first lich and as soon as the demi-lich appeared, I cast(used a scroll) protection from magic on my fighter, moved everyone else away and he focused on the fighter but couldn`t do anything, the fighter literally ripped his head off in a matter of seconds. It was my first -and last- time fighting him also (thanks to the board for the protection from magic trick though).

If you have a druid, summon a fire elemental. Their attacks are counted as +4 or +5 and they do great damage to Kangaxx. Just make sure you cast Protection from Magic on it, or have a fighter tanking, or something.