You enter plain of shadow, go into the building using the front door, then head to the north-west corner of the building. Make sure to have invis to undead up, and you will get there without unwelcome adds.

There is a round room with stairs leading up (where additional undeads can be found, in case you run out of enemies). Under the stairs is a small safe area, where you can start your killing session. You kill the undead creatures there using root-rot or pet-tank. There is not enough room for kiting, until you cleared at least three mob. They are all level 100, so the xp is pretty good. All mobs can be single pulled, though there are two small groups that need a bit of split work, but they can even be ignored, if your dps is anyway too low to clear the whole room. There is one roamer moving on the stairs, and one is wandering near the entrance door, but none is walking through the room.

All mobs can be snared and rooted, beside the named, the dark lady. She drops a nice tashan-clickie and can be soloed with pet tanking.