Ok, if you didn't know this, and want some extra experience for the group, then read on.

The dogs always attack you right outside when you attack the Otyugh in D'Arnise Keep. Well, don't worry about killing them, just do it. You won't lose any reputation, and they always attack first anyway, it's self-defense. Gather up the dog meat and go inside D'Arnise Keep. Now, before you go and encounter the Umber Hulks in the Cellar, go to the kitchen and use the stove 5-6 times. You emptied all of the dog meat in it, and now the stew is cooked. Before you encounter the Umber Hulks, make sure to improve invisible someone, or use hide in shadows to get past the Umber Hulks with one of your characters. Now, if you know where the Dungeon with the tunnel in it is at, go there and click on the spot with the dog bones. Now drop the Stew in that spot to gain experience, make sure to hide in shadows again. If you want more experience, set up a whole bunch of traps down there to kill off the first few Umber Hulks, and use any theives or rangers in your group to attack the Umber Hulks using Hide in Shadows. Also, some invisible people will help as well.