What characters are you playing? All I gotta say is "Magic Bomb" my friend, Magic Bomb, can kill enemies from afar so you don't get hurt, plus works through walls in some cases (not all, but many). Plus running about like a freak is always handy, standing still can get you killed quick when you are overwhelmed. Lure em out one by one method works well, and, of course, Magic Bomb! Did I already mention Magic Bomb? Oh, OK, sorry, I'll shut up now...