Fljotsdale: this worked very well for me:
Equip Imoen or the thief in your party with invisibilty potions -loads of them. In fact, go out and buy extra if you need them.
Then, position your party out of sight in the back room and have Imoen walk up the the Dwarf. Solve the riddle and as the dwarves attack, have her go invisible (Stealth won't work in the sight of enemies so you have to use potions). They will stand around in their red circles 'cause there is no one to attack. Position Immy behind one of them and backstab with a decent sword. Hit pause and immediately have her drink a new invisibility potion. Repeating this a couple of times will have to major bonuses: 1. if you get a decent back stab in, it makes the kill much easier. 2. as soon as Imoen becomes visible from the backstab, the dwarves will start attacking and spellcasting, and in my game, this often resulted in the dwarves fighting each other because they got struck by each other's Skull Traps and Cloudkills.... sneaky!
As soon as they are sufficiently weakened by this tactic, barge in and mop up remains
GOOD LUCK!! (I thought they were really though as well!!!)
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Melusine, High Queen of Fluffies, Archbabe of the OHF, the LH,
the HADB and the SPAE(Society for the
Prevention of Acronym Extinction) &
Official Entertainer Elf of the BG2 Bar
Your voice is ambrosia