I have to say....definitely Endermen. Why? Because they get angry if you just LOOK at them,and then they're all and then they teleport behind you and just try to MURDER you.....for LOOKING at them! Plus,if you look at them by accident.... it's a real "OMG IM SCREWED'' moment. Plus their horribly creepy shriek isn't something to make you feel confident. They have everything the other overworld monsters have,only better:they're creepy,they're difficult to kill,they're griefers,and they have some overpoweredness. Endermen are just so scary when I see one I RUN. Basicly,the most ferocious,creepy,and stealthy mobs EVER. Hope they win...(Enderman shriek)