Do you know the best way to handle the spell Shrapmetal? Your necromancer should have it, and, used properly, it is the most destructive spell in the game. What you do is pick one opponent, rush up to it until you're right in contact range, and then hit Return to enter turn-based mode. Then cast the spell when your necro's turn comes up. If your necro has GM in Dark magic, he/she will cast 9 fragments of metal, each doing a minimum of 10(1d6+6) - an average of 95 - points of damage, and that single opponent will get the benefit of every last one of them. Even though your opponent's resistance will degrade the attack somewhat, there's not much that will stand up to that treatment for long.

If you can chop one opponent down before you have to run and heal, you can clear the position, although having to run and heal repeatedly will take quite some time and your party's armour will be in tatters by the time you've finished.

2)Kill the weakest first - by killing weakest monsters first you reduce damage that you take in fight troughout and also you make fight easier for you, to not have to risk so much killing strong monster.

3)Use combat tactics like trying to confuse opponents - going behind corners where they cant see you, charming them, berzerking, using arrows from afar before entering melee combat(or fireballs before incinirates or whatever mages have there, i usually play might

3)If you tryed first three steps and you still cant kill the single monster - go to alchemist/magic item shop and get all scrolls/potions/wands you can get(like resistances, divine cures, berzerk, charm, enslave, power cure, wands of single/multiple target damage, paralysis, hour of power) and try again using all you have on first monster.

4)If still no luck maybe try to get some expirience and more levels and next time you come you wont have any trouble at all! There could be huge difference between level 25 and 27 while from first glance you might think its nothing much.