I'm going to have to try this myself relatively soonish with two characters. One has no magic so I'm planning on piling on as much regen through shrines and food as possible. The other, same thing but stacking healing grace with soothing rain and.. on that other one I can't remember how to pronounce from the sun school. Might actually keep my alive long enough to finish. Guess I'll see what happens.. Of course, none of that is going to do me any good if I can't find the way down!