Minecraft wiki entry for Tips_and_tricks, associated text: If you are stuck outside in the middle of the night with many hostile mobs coming to attack you, you can make an emergency shelter. Ideally, you should dig three blocks down and place a block above you, making a cramped yet safe area to stay in. You should have a torch however; if you wish to avoid being in the dark without a light source. If the monsters aren't already too close, you can even dig out more space to place a bed. You can get out of the hole by pillar jumping if you do not have any ladders. This method is not terribly though, as you are completely exposed to mobs as you leave.