I took them at the Selune temple. I was *hoping* that the lasers would blast them, but that didn't work. Since that didn't work, strategy was:
-position everyone on the very top of the gate
-close the gate
-use infinite warlock imps to lure them to your position slowly (you could probably do it with mage hand too)
-rain doom down on them
One of them jumped up and messed with us, but we were able to deal with it before the other one arrived. You could probably be more effective by strategically placing explosive barrels outside the temple too.