Wyrm's tooth
Snow trolls - need acid & fire.
Greater Yetis - If you can't take these on by now you need help. Go back to BG2
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Frost Salamanders & white wolves - Protection from cold is helpful here, keep the unprotected back, the white wolves have quite a blast radius and the salamanders will cause damage to those close to them every round or so. Otherwise they're not too difficult to kill and can be lured out group by group.
Frost Giants - You can wipe these out for stacks of experience. Go and cajole Jorril into giving you his badge. Then attack him. Have your party waiting. You may want to have a lone thief or mage harrangue Jorril and his body guards. Poison is good. When they have fallen back to your party, web/grease them or confuse etc. Then use ranged weapons (especailly sling: giantkiller). You can then lure the giants out 1 by when you have killeds Jorrill and his body guards. I like using my ranger to charm the white wolves in the area and set them on the giants
http://www.gamebanshee.com/ubb/biggrin.gif Dont be stingy with powerful weapons like acid arrows.
Black ice nights & Kontik - toughies again. Start with a few fireballs on the closest nights, then its defensive line time again - don't draw too many at once. Then its the old haste & strength. Magic works OK but you need to kill them quickly 'cos they deal out stacks of damage. Kontik is tough. I usally leave him/her? till last, thief backstab and charge with my entire party otherwise a few nasty spells go off. Some Spellcasters in IWD have teh nasty ability of not being disrupted while they cast.
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