I would of suggest to add Criminal NPCs like the shinobi that lefted villiges. They will just walk around map in groups of 1-5. If they see you they going to team you and then chop ya into pices and eat you. They will also attack in bigger groups of maybe 10 villiges sooooooo if all villige NPCs are death and they come wellllll good luck for newbies. There could also be mission to track down and kill some of them.