Minecraft wiki entry for Defeating_the_ender_dragon, associated text: Beds can be extremely useful for dealing large amounts of damage to the dragon. Placing them down when the ender dragon is on the portal and blowing them up removes up to 1/5 of the ender dragon's health. Although this is a good strategy it is extremely dangerous and you have to be careful. The main way to not take damage is going inside the ender portal, placing a bed, putting a block next to that bed and then right-clicking. Doing this negates the damage to 0 as the explosion does not go down to hit your legs and the block you placed prevents your head from being hit.