Logic

This is a year old I realize, but (*shrugs) Sulfras can indeed be killed. The black shades can't be. After killing sulfras, just leave without killing the black shades (the pillars) which can't be affected. Come back for the treasure which has high-level dread curses that come with it and steal the boots and cloak in the room. Just make sure you have enough potions, beast ceremony, arcane shield to protect you from the wrath of the black shades. You should probably only do this after sulfras allows you to go through (meaning after you fulfill his quest) -Logic