Notice this seems to be a theme whether or not its vanilla or modded but npc's and npc groups seems to have very wide range in damage output... Some enemies I encounter can't even scratch me, while others can kill me in 1-2 hits... sometimes these are even part of just one group... I know the level can range somewhat but it doesn't even seem to have much to do with what weapon they're wielding... damage just seems to have huge jumps.