Look. Here's the best way to defeat the Balor in the Fire Node. Keep a good distance between your party and it. This means do not charge it and start trying to chop at it. All you will do is irritate it and make it mad. This will lead to your defeat. You need three spell slingers all casting level 5 spells. Step 1 is for the Wizard to initiate combat in front of the party by casting a Cone of Cold once or again in the 2nd round to kill the two creatures around it. Step 2 in round one is for both the Cleric and Druid to start putting spiritual weapons and also Summon Type-4 (and -5) elementals around it, especially between your party and it. You need to be able to keep at least two, preferrably more than two, spiritual weapons and, or elementals around it at all times. When you run out is when you have to go hand-to-hand because it will kill one thing every round regardless of what you put in front of it. Whenever it casts a spell, that's extra round of summon spells against it. The most effective summoned against a Balor is a polar bear summoned by a druid which has Animal Growth cast on it by a wizard in the same round. Step 3 is to use all your cone of cold, magic missiles, fireballs, ice storms, scortching rays, searing light, etc. Lightning is not effective at all against a Balor. Do as much damage spell wise at a distance as is possible before having anyone attempt to charge and attack it.