Minecraft:Monster Spawner

Template:Infobox block A monster spawner is a type of Minecraft:spawner found in a variety of Minecraft:structures. It constantly summons instances of the Minecraft:mob displayed within it as long as a Minecraft:player is in range and the light levels are correct for that mob type to spawn nearby. It only drops Minecraft:experience orbs when broken, and cannot be moved from where it is found.

Obtaining

Monster spawners cannot be obtained in Survival, even with Minecraft:Silk Touch.

A monster spawner can be obtained in Minecraft:Creative mode by taking it from Creative inventory, by using the Template:Cmd Minecraft:command, or by using Template:Control. It is initially empty and inert, but can be configured to spawn a desired mob by Template:Control a Minecraft:spawn egg on the placed block.

A Template:Cmd, Template:Cmd or Template:Cmd command can also be used to obtain a monster spawner.

Breaking

If broken with a Minecraft:pickaxe, a monster spawner drops 15-43 Minecraft:experience. When mined with anything else, it drops nothing. Template:Breaking row

Natural generation

Monster spawners can generate naturally in the following places:

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One in the center of the monster room spawning one of the following mobs with the indicated frequency: Minecraft:zombie (50%), Minecraft:skeleton (25%), or Minecraft:spider (25%).

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Any number of Minecraft:cave spider monster spawners, densely surrounded by Minecraft:cobwebs, scattered throughout.

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Optionally one Minecraft:spider monster spawner, densely surrounded by Minecraft:cobwebs, in a rarely generated secret room on the 2nd or 3rd floor. It is sometimes visible through the windows from outside.

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One Minecraft:silverfish monster spawner in the Minecraft:end portal room.

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One or two Minecraft:blaze monster spawners on fenced platforms with full-block "stairs" leading up to them. Normally two are generated per fortress, but there can be fewer.

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One Minecraft:magma cube monster spawner hanging from an Minecraft:iron chain underneath a bridge in treasure rooms.

Usage

A monster spawner spawns mobs in an (at most) 9×3×9 volume (see Template:Slink) around it when the player is within 16 blocks. Suitable spawning locations for the block's mob type are provided in or around the spawning volume. The monster spawner attempts to spawn four Minecraft:mobs around it, then waits from 10 to 39.95 seconds before attempting to spawn more.

In Minecraft:Peaceful difficulty, monster spawners still activate but do not spawn Minecraft:monsters, including Minecraft:zombie horses and Minecraft:camel husks Template:In.

Monster spawners are Minecraft:transparent, but they behave like Minecraft:leaves in that they diffuse sky light coming from directly above.

Mechanics

A monster spawner activates when a Minecraft:player (that's not in Minecraft:Spectator mode) comes within a spherical radius of 16 blocks from the center point of the block; i.e. 15.5 blocks from the monster spawner itself. The player's presence is determined by coordinates at their foot level, meaning that a player standing exactly 15.5 blocks below the spawner doesn't activate it, even though their head is in range. Template:IN an active monster spawner attempts to spawn mobs within a 4-block horizontal and 1-block vertical range; that is, in a 9×3×9 volume centered on the monster spawner. Template:IN, the horizontal spawning range is 4 blocks Minecraft:taxicab distance, creating spawning volume extending 4 blocks in each cardinal horizontal direction from the sides of the monster spawner; its horizontal cross-section is therefore diamond-shaped. Mobs can spawn anywhere in this range that is suitable, with mobs more likely to spawn closer to the monster spawner than farther away.

While mobs are spawned at fractional x and z-coordinates (i.e. not aligned to blocks), they are spawned at an integer y-coordinate. Horizontally, a mob can spawn with its center point anywhere within range, but vertically, mobs spawn with their legs at either the same layer as the monster spawner block, one block above it, or one block below it. (Note that when there are other blocks slightly intersecting the mob's hitbox, they can sometimes glitch further away - often up - but this does not make it a true spawning point.)

A monster spawner attempts to spawn 4 mobs at randomly chosen points within the spawning volume, then waits anywhere from 200 to 799 ticks (10 to 39.95 seconds) before spawning again. As it waits, the mob model inside the block spins faster and faster. Except for the normal solid-block spawning requirement, all the remaining ones must be met (not in a solid block, correct light level, etc.), so the monster spawner often produces fewer than 4 mobs. When it does spawn, more flame particles temporarily appear around it, and puffs of smoke are emitted from the spawned mobs Template:In or the northwest corner of the spawner Template:In. If the monster spawner fails to spawn any mobs because it did not pick any suitable locations, it repeats this process every Minecraft:tick until it succeeds. It starts the next wait cycle only after successfully spawning at least one mob.

If 6 or more mobs of a monster spawner's type have their Minecraft:hitbox intersecting a 9×9×9 volume centered on the monster spawner block Template:In or a 16×10×16 volume centered on the lower northwest corner of the monster spawner block Template:In, the monster spawner "poofs" without creating any mobs and then waits for the next cycle.Template:Needs testing This is checked before each of the four spawn attempts.

Spawning requirements

A monster spawner performs a relaxed version of the ordinary spawning check: the general solid block requirement is removed, but the volume (hitbox of the mob) is kept along with some other checks according to mob specifics. As a result, for some types of mobs to spawn in the outer planes of the spawning volume, some planes outside the volume may also need to be free of solid blocks to conform with the mobs' height, width, or other rules governing their individual spawn volumes. Examples:

• For mobs that are two or more blocks tall such as zombies, skeletons, or blazes to spawn in the top y-layer, the layer above must contain only a transparent block such as Minecraft:air, Minecraft:glass, Minecraft:leaves, etc.
• Template:IN, a turtle monster spawner can spawn turtles only on Minecraft:sand blocks less than 4 blocks above sea level (typically at Y=62). Template:IN no biome/light/height conditions apply for turtles in monster spawners.
• Template:IN, some animals require light level ≥7, e.g. chicken, sheep, cow, rabbit. Others ignore the light level condition given in the spawning rules json files, e.g. parrot, turtle. This suggests that some of the early animals have hard-coded requirements when used in monster spawners.

Summary of maximum spawn volumes for common monster spawners

Mob type	Required Volume (Java)	Required Volume (Bedrock)Template:Verify	Vertical alignment
Template:EntityLink<ref group="note">Pig monster spawners do not appear naturally in vanilla Minecraft.</ref>	8.9×2.9×8.9		Template:BlockGrid
Template:EntityLink	8.7×2.5×8.7		Template:BlockGrid
Template:EntityLink	8.4×2.3×8.4		Template:BlockGrid
Template:EntityLink	8.6×3.95×8.6	8.6×3.9×8.6	Template:BlockGrid
Template:EntityLink	8.6×3.99×8.6	8.6×3.9×8.6	Template:BlockGrid
Template:EntityLink	8.6×3.8×8.6	8.5×3.8×8.5	Template:BlockGrid
Template:EntityLink	9.4×2.9×9.4		Template:BlockGrid
Template:EntityLink	10.04×4.04×10.04	10.08×4.08×10.08	Template:BlockGrid

For all of the volumes listed in the table, the horizontal plane is centered on the center of the monster spawner. While the spawning volume for pigs is 8.9×2.9×8.9, the requirement of grass blocks that are necessary for pigs to spawn reduces the actual volume in which they successfully spawn to 8.9×1.0×8.9. Other mobs can spawn in mid-Minecraft:air, ignoring general rules about spawning on solid ground.

The spawn conditions do not include biomes for most mobs. As such, monster spawners can place mobs where they normally wouldn't generate. For example, a mooshroom monster spawner can operate in a plains biome as long as there are mycelium blocks within the spawn area because the mooshroom's spawning code checks only for mycelium. The reason mooshrooms are not actually spawned elsewhere is that the game does not normally try to spawn them in other biomes: only the mushroom field biome has mooshroom on the list of things to spawn.

Disabling

File:BlazeDisableGrid.png

Disabling a blaze monster spawner with nine blocks. Glowstone can be replaced with other light sources of light level 15.

File:Disabled blaze spawner.png

Blaze monster spawner disabled by four jack o'Lanterns. This works only Template:In in small rooms.

File:MagmaSpawnerGrid.png

With the clever placement of nine solid blocks, a magma cube monster spawner can be completely disabled. Only the cobblestone is needed, glass is just for distance marking.

Template:See also The way a monster spawner can be disabled depends on the entity it tries to spawn.

For a monster spawner that generates mobs that spawn only in dark conditions (light level = 0), a Minecraft:torch placed on any side or top of the monster spawner is sufficient to disable it for the whole 9×3×9 volume.

For a Minecraft:blaze or Minecraft:silverfish spawner, a light level of 12 is required to prevent spawning. This can be achieved by:

• Laying 9 blocks in the pattern shown on the right using blocks having a luminance value of 15
• Laying a dense 7×7 grid of torches on the monster spawner's Y level
• Template:IN, placing a light source of level 15 on four surfaces

A monster spawner is also disabled by filling the spawning volume with Minecraft:solid blocks. This is often used to disable Minecraft:magma cube monster spawners, as magma cubes can spawn in any light level. However, since all magma cubes require the space of a large magma cube in order to spawn, a clever placement of as little as 9 solid blocks a layer above the monster spawner (see right image) can completely disable it.

Custom monster spawners

File:Example monster spawner - Spider.png

A monster spawner in a monster room that produces spiders.

Template:IN, using Minecraft:commands, monster spawners can be customized:

• They can be made to spawn any kind of entity.
• A single monster spawner can spawn multiple different entities, chosen at random from a list.
• Properties can be set on the spawned entities.
• Various range and timing properties of the monster spawner can be changed.

Detailed technical information about custom monster spawners can be found below.

Template:IN, monster spawner customization cannot be done in the base game (i.e. without addons/behavior packs).

Note blocks

A monster spawner can be placed under a Minecraft:note block to produce "bass drum" sounds.

Piston interactivity

Monster spawners cannot be pushed by Minecraft:pistons. They also cannot be pushed nor pulled by Minecraft:sticky pistons.

Sounds

Template:El: Template:Sound table/Block/Monster spawner/JE Template:El: Template:Sound table/Block/Monster spawner/BE

Data values

ID

Template:Edition: Template:ID table Template:ID table

Template:Edition: Template:ID table Template:ID table

Block data

A monster spawner has a block entity associated with it that holds additional data about the block.

Template:El: Template:See also

<section begin="block data"/>

• Template:Nbt Block entity data
  • Template:Nbt inherit/blockentity
  • <section begin="spawner data"/>Template:Nbt: Ticks until next spawn. If 0, it spawns immediately when a player enters its range. If set to -1 (this state never occurs in a natural spawner; it seems to be a feature accessed only via NBT editing), the spawner resets this and Template:Cd as though it had just completed a successful spawn cycle, immediately when a player enters its range. Setting this to -1 can be useful if the player wants the game to properly randomize the spawner's Template:Cd and Template:Cd, rather than starting with pre-defined values.
  • Template:Nbt: Overrides the maximum number of nearby (within a box of Template:Cd*2+1 × Template:Cd*2+1 × 8 centered around the spawner block) entities whose IDs match this spawner's entity ID. This is relative to a mob's hitbox, not its physical position. Also, all entities within all chunk sections (16×16×16 cubes) overlapped by this box are tested for their ID and hitbox overlap, rather than just entities within the box, meaning that a large amount of entities outside the box (or within it, of course) can cause substantial lag.
  • Template:Nbt: The maximum random delay for the next spawn delay. Requires the Template:Cd and Template:Cd properties to also be set.
  • Template:Nbt: The minimum random delay for the next spawn delay. May be equal to Template:Cd. Requires the Template:Cd property to also be set, otherwise it defaults to 0.
  • Template:Nbt: Overrides the block radius of the sphere of activation by players for this spawner. For every gametick, a spawner checks all players in the current world to test whether a player is within this sphere. Requires the Template:Cd property to also be set.
  • Template:Nbt: How many mobs to attempt to spawn each time. Requires the Template:Cd property to also be set.
  • Template:Nbt: Contains tags to copy to the next spawned entity(s) after spawning. Any of the entity or mob tags may be used. If a spawner specifies any of these tags, almost all variable data such as mob equipment, villager profession, sheep wool color, etc., are not automatically generated, and must also be manually specified (that this does not apply to position data, which are randomized as normal unless Pos is specified. Similarly, unless Size and Health are specified for a Slime or Magma Cube, these are still randomized). This also determines the appearance of the miniature entity spinning in the spawner cage. Warning: If Template:Cd exists, this tag gets overwritten after the next spawning attempt: see above for more details.
  • Template:Nbt: Optional. List of possible entities to spawn. If this tag does not exist, but Template:Cd exists, Minecraft generates it the next time the spawner tries to spawn an entity. The generated list contains a single entry derived from the Template:Cd tag.
    • Template:Nbt: A potential future spawn. After the spawner makes an attempt at spawning, it chooses one of these entries at random and uses it to prepare for the next spawn, overwriting Template:Cd.
      • Template:Nbt: The chance that this spawn gets picked in comparison to other spawn weights. Must be positive and at least 1.
      • Template:Nbt
        • Template:Nbt inherit/spawn data
  • Template:Nbt: The radius around which the spawner attempts to place mobs randomly. The spawn area is square, includes the block the spawner is in, and is centered around the spawner's x,z coordinates - not the spawner itself. It is 2 blocks high, centered around the spawner's y coordinate (its bottom), allowing mobs to spawn as high as its top surface and as low as 1 block below its bottom surface. Vertical spawn coordinates are integers, while horizontal coordinates are floating point and weighted toward values near the spawner itself. Default value is 4.<section end="spawner data"/>

<section end="block data"/>

Template:El:

See Minecraft:Bedrock Edition level format/Block entity format.

Videos

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History

Trivia

• Monster spawners containing Minecraft:zombies can never spawn a Minecraft:zombie villager.<ref>Template:Bug</ref>
• Template:IN, monster spawners containing Minecraft:zombies have a small chance to spawn a Minecraft:chicken jockey.
• Monster spawners containing Minecraft:zombies or Minecraft:skeletons have a chance for the mob spinning inside to have armor.
• Monster spawners containing Minecraft:spiders have a small chance to spawn a Minecraft:spider jockey.
• Template:IN, monster spawners containing Minecraft:pillagers have a small chance for the mob spinning inside to be a Minecraft:raid captain.
• Template:IN, the Minecraft:iron golem inside an iron golem spawner is apparently on very low health, visible by the cracks.
• Monster spawners in Minecraft:mushroom fields, the Minecraft:deep dark or Minecraft:the Void biome can function normally, despite those biomes having no hostile mobs spawn naturally.
• It is possible for an empty monster spawner to generate naturally. If a newer world is loaded in an older version of Minecraft, the monster spawner can lose its block entity data, causing it to enter its default state, which is an empty monster spawner. Alternatively, if a Minecraft:buried treasure chest generates next to a monster spawner, it duplicates the monster spawner without duplicating the NBT tag, resulting in a natural empty monster spawner.<ref>Template:Bug</ref> The chest also gets invalid block (monster spawner) data, making it unopenable.
• A monster spawner does not preserve its NBT data when placed in Survival mode.<ref>Template:Bug</ref> It requires the player to be in Creative mode and have permission level greater than or equal to 2.

Gallery

Renders

Spawner

• 
• File:Pig Spawner.png
• File:Zombie Spawner.png
• File:Skeleton Spawner.png
• File:Spider Spawner.png
• File:Cave Spider Spawner.png
• File:Silverfish Spawner.png
• File:Blaze Spawner.png
• File:Magma Cube Spawner.png

Structure

• A Minecraft:blaze monster spawner in a Minecraft:nether fortress.
  A Minecraft:blaze monster spawner in a Minecraft:nether fortress.
• Spider monster spawner in a Minecraft:woodland mansion.
  Spider monster spawner in a Minecraft:woodland mansion.

Screenshots

• A Minecraft:monster room, connected to another monster room, with two monster spawners.
  A Minecraft:monster room, connected to another monster room, with two monster spawners.
• A monster spawner edited to spawn Minecraft:zombies wearing enchanted diamond Minecraft:armor.
  A monster spawner edited to spawn Minecraft:zombies wearing enchanted diamond Minecraft:armor.
• Light required to disable a blaze monster spawner.
  Light required to disable a blaze monster spawner.
• A monster spawner that spawns Minecraft:skeletons.
  A monster spawner that spawns Minecraft:skeletons.
• A Minecraft:spider monster spawner that generated on the surface. The monster spawner is located roughly in the middle of the picture, underneath a Minecraft:cobweb.
  A Minecraft:spider monster spawner that generated on the surface. The monster spawner is located roughly in the middle of the picture, underneath a Minecraft:cobweb.
• Minecraft:Chickens spawning from multiple monster spawners.
  Minecraft:Chickens spawning from multiple monster spawners.
• A monster spawner in an older version of Minecraft.
  A monster spawner in an older version of Minecraft.
• Cave spider monster spawner seen from a chamber.
  Cave spider monster spawner seen from a chamber.
• A Minecraft:magma cube monster spawner inside the Minecraft:bastion remnant.
  A Minecraft:magma cube monster spawner inside the Minecraft:bastion remnant.
• A spider monster spawner connected to a Minecraft:mineshaft.
  A spider monster spawner connected to a Minecraft:mineshaft.
• Two Minecraft:blazes spawned near a blaze monster spawner and a Minecraft:wither skeleton.
  Two Minecraft:blazes spawned near a blaze monster spawner and a Minecraft:wither skeleton.
• Pig monster spawners generating when a buried treasure chest spawns inside a monster spawner (Fixed in 1.17 pre-1).
  Pig monster spawners generating when a buried treasure chest spawns inside a monster spawner (Fixed in 1.17 pre-1).
• Amethyst geode with mineshaft and 2 cave spider monster spawners. Check the image for more details, including seed and coordinates.
  Amethyst geode with mineshaft and 2 cave spider monster spawners. Check the image for more details, including seed and coordinates.
• 2 cave spider monster spawners next to each other.
  2 cave spider monster spawners next to each other.
• Spider monster spawner generated right next to the village.
  Spider monster spawner generated right next to the village.
• Mineshaft and skeleton monster spawner generated at the bottom of the world.
  Mineshaft and skeleton monster spawner generated at the bottom of the world.
• A close-up view of am iron golem spawner, with visible cracks in the golem.
  A close-up view of am iron golem spawner, with visible cracks in the golem.

See also

• Template:EntityLink
• Template:BlockSprite Monster spawner traps
• Template:BlockLink

External links

• Block of the Week: Spawner – Minecraft.net on January 13, 2022