A tad late with this, and some adventure logs need writing up. Blah blah dwarves kidnapped, blah blah duergar, blah blah old foundry, blah blah hard to hit AC23.
Into the basement of the duergar foundry, and the final fight. One v nasty duergar theurge who threw around lots of area burst 2 attacks, causing much carnage, and 4 magma runners. These guys ran into magma and ran past people. If you took an opportunity attack against them, you took 5 damage from the flames. Fairly horrid, but a lot easier to hit than the duergar. And an imp that didn’t do much other than go invisible and run away at the end.
Another win for the good guys though. The kidnapped dwarves you were searching for may have been sold into slavery to some orcs in the Stonefang Pass – a mountain range near Hammerfast. There was a nice hammer for Bronale, +1 but dishes out ongoing 5 on a crit.