Minecraft wiki entry for Player_versus_Player, associated text: In addition to the extremely thick layer, smartly add multiple types of layers to your wall: Solid: solid layers of obsidian with no gaps, this should make up the majority. Liquid: a layer of water or lava, put one on the outside to prevent explosions, and some on the inside to delay the enemy charging in. Also used for the roof and perhaps floor of the wall. Height: should be the solid type, used to stop elytras, cannons and climbers, best with a lava shield, at least at the bottom to kill elytra pilots. Don't put them too outwards. Another variation is to use tons of sand and gravel,(expensive to get normally) not to use against elytras, but to fill down the wall that the enemies broke, causing a huge delay. If they use torches, the massive amounts of dropped items (if it is built up to the height limit, or as high as possible if the server has mods) may crash the server and undo their work, if they charges in while it's lagging, they may get buried! Checker: put multiple layers of clay, wood, obsidian, liquid or cobwebs (choose two from those) in a checkerboard pattern. As they are mined with different tools, enemies must switch tools constantly (most of them won't bring shovels, shears, and axes at all!) in order to get pass them, and it's hard for them to climb if liquid is one of the materials. Cobble: use water and lava in a single layer accordingly to continuously generate cobblestone, these can't be mined through without enough intelligence,(a wrong step in disarming it may leak liquid out which drowns/burns players) and is usually explosion (wither) proof! Fill any other space in that layer with obsidian. Room: make an empty space without lighting to spawn monsters in it, all walls around it should have no liquids. One can put it around a spawner to maximize its potency, or lure some exotic monsters in and lock them (wither cages). When the enemies break the surrounding walls, an array of monsters (which spawns while they are near and mining through the other layers difficultly) will flood out! Trap: add buds to random parts of the wall and connect them to TNTs, when the enemy unfortunately mines the parts, BOOM! one can also add a semi-wall of TNT to stop massive amounts of raiders if necessary, make sure not to put lava layers near! As long as obsidian can't be blown up due to plugins, these shouldn't damage your walls. All other traps can be used if one knows how to!