Minecraft wiki entry for Multiplayer_PvP_bases, associated text: A much better stategy is to spawn as much withers as possible. The wither will fire at any living life form (including the guardian around the base. Many players don't know that the wither can fire out blue skulls that can destroy even obsidian submerged in water. Now, let the wither bring havoc and act as a distraction as you loot the base.