I like this fight in Baldur’s Gate – it’s the battle with Sarevok’s acolytes atop the Iron Throne headquarters in the city of Baldur’s Gate. They make for tough opponents unless you’re prepared, since they are a well-balanced group of fighters, priests, and mages.
I’ve found the best strategy is to take out the mages and clerics first and then to focus on the fighters. Using buffs and protection spells and potions is often necessary.
My Baldur’s Gate character, of course, is named after the protagonist of my FROSTBORN fantasy series.