At the beginning og the fight most likely the balrog kills every one but idrial.use elf medicine to revive her then heal gandalf then her. DO NOT heal anyone else because as long as you dont have more then two people then the balrog wont using his one hit kill moves.keep using gandalfs attack and heal gandalf and idrial with idrial and when the party runes low on ap points then use gandalfs move to get them back for the party.eventually you will kill the BALROG.