Minecraft wiki entry for Survival_in_an_infinite_desert, associated text: You can also use the Shaft method to dig illumination shafts into your staircase once it starts disappearing a long way under the sandstone. However, don't do this until you are deep enough that the fall is certain to kill any mobs that fall down the shaft. Also, don't forget your big sand stack, just in case you make a mistake and fail to connect with your staircase, meaning you can't walk out, you must pillar-jump out.