This might be another bug related to Battle fields, im in act II on the second battlefields level, now the two dungeons in the battle fields ive been able to go too have been populated with monsters (archers, mages and mutants) but the top floors, were you usualyl get quest items/monsters were empty <img src="/ubbthreads/images/graemlins/confused.gif" alt="" />
~Cent~
