Shields aside, lox were buffed to be more aggressive, and there are new deadly blob enemy in the plains and a new deadly monster (that respawns rapidly) in the swamp, and new ice caves that can be a deathtrap to the unwary. The old monsters are mostly about the same, or weaker even (poison seems to be far reduced from what it was, you can all but ignore the shaman in the forest and leeches now, within reason...) but the new content is a small step up in challenge..