Thats easy I have beat it on ever difficulty so I know what you are talking about, I walk very slowly, only let one pop up at a time, I never use the dwarf, but if you have any of the other characters just bomb on them from a far, hit and run, have plenty of potions, and never go head to head with them unless your really strong, and even then its just a waste of potions, I like the Archer - lightning arrows work wonders, they are a life saver.