My party consisted of:
Human: Fighter 3/ Conjurer X
Human: Fighter 3/ Transmuter X
Human: Fighter 3/ Cleric X
Elf: Fighter/thief multiclass
I cleared the game on very hard and it was VERY EASY! I started with three characters but after a while i added my fourth character (the conjurer). If I felt like it, I would use the DeadZone tactic (lot's of Web and Cloudkills/fireballs + Bow shots) or I would just buff upp all my party members with Haste, Prayer, Emo: Hope, Emo: Courage and stuff like that and engage the enemies in melee or ranged combat. I killed Behlifet in 20 seconds without sustaining any serious damage. A pretty good party....
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