Minecraft wiki entry for Survival_in_an_infinite_desert, associated text: An alternative approach is to make your spiral steps go down half the way around, then come back up again. This has the advantage of giving you at least one escape route. It allows you to lure a creeper down one entrance, to try to get it to explode at the bottom, and still escape through the other exit. It might be an idea to block the exit with sand blocks to make sure you don't have another mob blocking your way when you try to escape.