My balance wizard got lucky and found her hat and cape on the first run, but it took another few tries for her boots; my necromancer's boots also eluded him, and my poor Storm wizard was level 75 before she got her robe...
AND THEN my Life wizard goes in and, on her FIRST TRY, gets her robe AND a storm mastery.
Point is, all gear drops are random~ patience is a virtue (which Dr. Von admittedly lacks, but a virtue nonetheless).
