Mob Spawners (or Monster Spawners) are Blocks with a transparent, black, cage-like, lattice structure found in various locations. Inside the block are flame particles that don't give off any light and a miniature spinning version of the Mob it spawns. This will slowly increase in speed until the next group of mobs is spawned. When mined with a Pickaxe, they drop experience, but it cannot be obtained, even with the Silk Touch enchantment. In Minecraft: Bedrock Edition, they are available in the Creative inventory. In other editions of the game, the only way to obtain the block is by using commands.
They are one of the few blocks not obtainable in Creative Mode (except in the Bedrock Edition) unless commands are used. It is possible to get this block through the
/give command, but it will only spawn pigs, even with the correct details. However, the
/setblock command can be used to place monster spawners with a mob of a player's choice, provided that it is used with the correct NBT data. In the Minecraft: Pocket Edition from Update 0.9.0 and in the PC Edition, starting with snapshot 14w28b, the mob spawned can be set by using a Spawn Egg on it.
A mob spawner will create mobs, provided there is enough space for the mob to be generated, and the light level within the spawning radius remains below seven. Mobs are created within an 8×8×3 high area centered around the spawner's lower northwest corner. Note that mobs can spawn in any dark space within range, even if the spawner is fully lit. The spawner will only spawn mobs if a player is within 16 blocks of it. A common trend among seasoned players is to create mob traps around mob spawners for an easy way to gather that mob's resources with little or no danger to themselves.
- Dungeons — The most common area to find monster spawners. The spawners found in these areas can spawn Zombies, Spiders, and Skeletons. Zombie spawners will appear 50% of the time, while the other two have a 25% chance of appearing.
- Abandoned Mineshafts — These areas contain many useful items, as well as Cave Spider spawners.
- Strongholds — These areas contain the portals to The End, along with a single spawner in the portal room that spawns Silverfish.
- Nether Fortresses — Extremely large structures that have useful items found in The Nether, the spawners they hold spawn Blazes.
- Woodland Mansions - Rare structures found in roofed forests, there is a secret room that occasionally generates which has a spider spawner inside of said room.
Note: Monster spawners can only be obtained through mods and hacks, such as "TooManyItems", or by using the
Spawners can be used to make very effective "Mob Grinders", as they spawn more mobs faster when a player is in the spawner's vicinity. The best way to make one is by first make a large dark room around the spawner, then place down a "floor" 3–5 blocks below the spawner. Next, on the "floor", place down Water so it "funnels" the mobs that spawn into a hole in the "floor" which will lead wherever a player wants it to. Once the mobs are all gathered in the desired location, a player can either kill them manually or kill them with a Redstone contraption, and finally harvest the experience and items the killed mobs dropped.
Another option is to simply not place down any water and allow the mobs to take fall damage, which allows a player to kill the mobs more easily from a safer location. It is advised to light only the bottom of the pit. That way, the player will be less likely to encounter mobs other than the ones produced by the spawner.
- Mob spawners have an ID of 52, and they are named "Monster Spawner" in-game.
- Even though the spinning mob figure is much smaller than the actual mob, Ghasts, Ender Dragons and Giants are too big for the spawner to be seen.
- Monster spawners can spawn up to four mobs at once.
- Very rarely, a monster spawner can be found in out-of-the-ordinary locations.
- In the Minecraft XBLA (before the Christmas update in 2012), mob spawners would only show pigs, but they would spawn things other than pigs.
- Blaze spawners are the only type of spawners that are found naturally in the nether.
- If one uses the seed "Indev" when first creating a map, and then a player digs straight down from where they spawned, they will quickly find a dungeon with a zombie spawner.
- Monster spawners were added to Minecraft Pocket Edition via update 0.9.0.