Slime

Spawning[]

Slimes spawn in the Overworld in specific "slime chunks" below layer 40, regardless of light levels. They can also spawn in swamp biomes between layers 51 and 69 (inclusive) in light levels of 7 or less, with these layers tending to be near the surface. Slimes spawn regardless of weather conditions.

Only sizes 1, 2, and 4 (NBT Size tag values 0, 1 and 3 respectively) spawn naturally. With use of /summon, slimes can potentially range from size 1 to 127 (NBT Size tag 0–126).^[verify]

Like most other hostile mobs, slimes do not spawn within 24 blocks (spherical) of any player, despawn over time if no player is within 32 blocks, and despawn instantly if no player is within the despawn radius (128 blocks in Java Edition, 44 to 128 blocks in Bedrock Edition depending on simulation distance^[verify]).

A slime needs roughly a 3×2.1x3 free space to spawn. The area in which the slime spawns must be clear of solid or liquid obstructions. When a slime attempts to spawn, the game checks for the space requirement of a large slime, and the size is determined later. Therefore, since large slimes are slightly taller than 2 blocks, no slimes, regardless of size, are able to spawn at all in 2-block-high areas. Also, since large slimes are slightly wider than 2 blocks, and mobs spawn at the center of a block, having any block within the 3×2.1x3 area, even as thin as a glass pane, can prevent a slime of any size from spawning.

Slime size is affected by regional difficulty: chances range from 33% for each size at the low difficulty to 16% small, 33% medium, and 50% big with higher difficulty.

Slimes can spawn on some light-emitting blocks:

Swamps[]

In swamps and mangrove swamps, slimes may spawn between the heights of 51 and 69 (inclusive) when the provided light level is 7 or less. They spawn most often on a full moon, and never on a new moon.

More precisely, the game checks two factors:

1. If the light level is equal to or less than a random integer (from 0 to 7)
2. If the fraction of the moon that is bright is greater than a random number (from 0 to 1)

If these conditions are met and the altitude is acceptable, there is a 50% chance of spawning a slime.

The light level requirement for slime spawning in swamps is different from that of most hostile mobs, which only spawn at light level 0.^[1]

"Slime chunks"[]

Slimes spawn throughout the world (except mushroom fields and deep dark biomes) below level Y=40 regardless of light level, but only in certain chunks; ¹⁄₁₀ of all chunks.

Java Edition[]

In Java Edition, these "slime chunks" are determined pseudo-randomly by combining their chunk coordinates with the seed of the world:

import java.util.Random; 

public class checkSlimechunk {
    public static boolean isSlimeChunk(long worldSeed, int xPosition, int zPosition) {
        Random rnd = new Random(worldSeed
                   + (int) (xPosition * xPosition * 0x4c1906)
                   + (int) (xPosition * 0x5ac0db)
                   + (int) (zPosition * zPosition) * 0x4307a7L
                   + (int) (zPosition * 0x5f24f) ^ 0x3ad8025fL);
        return rnd.nextInt(10) == 0;        
    }

    public static void main(String args[]) { 
        long seed = 12345L; // the seed from /seed as a 64bit long literal
        int xPosition = 123;
        int zPosition = 456;
        System.out.println(isSlimeChunk(seed, xPosition, zPosition));
    } 
}

That is, using the chunk coordinates to help generate a seed, a random number between 0 and 9 inclusive is generated. If that number is 0, the chunk can spawn slimes. To convert world coordinates to chunk coordinates, divide by 16 and round down. Note that xPosition, and zPosition are 32-bit integers (ints).

As per Java Edition 1.20.5 snapshot 24W13A, 2 slimes can spawn whenever any entity affected by Oozing is killed.

Bedrock Edition[]

The slime chunk algorithm in Bedrock Edition is different from in Java Edition. The algorithm doesn't depend on the world seed, thus the chunks that slimes can naturally spawn in inhabit the same coordinates for every world.^[2]

Drops[]

If a slime's size is 1, it drops 0-2 slimeballs unless killed by a frog. This can be increased by 1 per level of Looting, for a maximum of 5 slimeballs. When killed by a frog, it always drops 1 slimeball.

Slimes also drop experience points equal to their size: 4 for large slimes, 2 for medium slimes, or 1 for small slimes. Because slimes split into 2-4 smaller slimes when they die, a player can earn a possible maximum of 28 experience points from killing one large slime and all the slimes that split from it.

Behavior[]

Slimes move by hopping, which they do every 10 to 30 ticks (¹⁄₂ to 1 ¹⁄₂ seconds), and can swim in water and climb ladders and scaffolding. Unlike other mobs, slimes continue moving when no players are nearby. Their exact routine is as follows:

The slime searches for a player (or, failing that, an iron golem) within 16 blocks (spherical) distance.

• If no target is found, the slime waits 10 to 30 ticks (¹⁄₂ to 1 ¹⁄₂ seconds) between jumps, and changes direction randomly every 40 to 100 ticks (2 to 5 seconds).
• If a target is found, the delay before jumping is ¹⁄₃ as long (3 to 10 ticks), and the slime's direction is set directly toward the target before jumping.

Unlike most mobs, slimes do not pathfind towards their target, always approaching their target in a straight line, without avoiding environmental hazards such as lava, cactus or dangerous falls. This means they can easily get stuck in corners or behind walls, not knowing how to circumvent them. This behavior is shared by magma cubes.

A slime's maximum health is equal to its size squared, and its dimensions are 0.51 blocks times its size in each dimension. When a slime attacks, it deals damage equal to its size, except for size 1 (smallest) slimes, which do no damage, and do not prevent sleeping. Because small slimes still have a hostile AI, they continuously attack the player.

A slime's jump distance also depends on its size; a slime jumps a distance slightly farther than its length. When landing, a number (8 times the slime's size) of slime particles appear. Slimes will always, regardless of size, jump 1 block high.

When a slime larger than 1 dies, it spawns 2-4 new slimes equivalent to its size divided by 2, rounding down. A slime that was named with a name tag produces smaller slimes with the same name when it dies.

Slimes continuously damage all players and iron golems‌^{[JE only]} they collide with (although damage immunity reduces the actual damage to 1 attack every half second), unlike other mobs that damage only those targets they specifically attack.^[3]

Slimes in water attempt to swim to the surface if possible. If forced to stay submerged, they eventually drown, splitting into smaller slimes that drown and finally drop slimeballs.

Sounds[]

Java Edition:
Slimes use the Hostile Creatures sound category for entity-dependent sound events.

Bedrock Edition:

Data values[]

ID[]

Java Edition:

Bedrock Edition:

Entity data[]

Slimes have entity data associated with them that contains various properties.

Java Edition:

Bedrock Edition:

See Bedrock Edition level format/Entity format.

Achievements[]

Advancements[]

Icon	Advancement	In-game description	Parent	Actual requirements (if different)	Resource location
	Adventure	Adventure, exploration and combat	—	Kill any entity, or be killed by any entity.	adventure/root
	Monster Hunter	Kill any hostile monster	Adventure	Kill one of these 34 mobs: Blaze Cave Spider Creaking Creeper Drowned Elder Guardian Ender Dragon Enderman Endermite Evoker Ghast Guardian Hoglin Husk Magma Cube Phantom Piglin Piglin Brute Pillager Ravager Shulker Silverfish Skeleton Slime Spider Stray Vex Vindicator Witch Wither Wither Skeleton Zoglin Zombie Zombie Villager Zombified Piglin Only the riders of the chicken jockeys and skeleton horsemen are counted in this advancement. Other mobs may be killed, but are ignored for this advancement.	adventure/kill_a_mob
	It Spreads	Kill a mob near a Sculk Catalyst	Monster Hunter	Kill one of these 70 mobs near a sculk catalyst: Axolotl Bee Blaze Camel Cat Cave Spider Chicken Chicken Jockey Cod Cow Creeper Donkey Dolphin Drowned Elder Guardian Enderman Endermite Evoker Fox Frog Ghast Goat Glow Squid Guardian Hoglin Horse Husk Llama Magma Cube Mooshroom Ocelot Panda Parrot Phantom Pig Piglin Piglin Brute Pillager Polar Bear Pufferfish Rabbit Ravager Salmon Sheep Shulker Silverfish Skeleton Skeleton Horse Skeleton Horseman Slime Sniffer Stray Spider Spider Jockey Squid Strider Trader Llama Tropical Fish Turtle Vex Vindicator Warden Witch Wither Wither Skeleton Wolf Zoglin Zombie Zombie Villager Zombified Piglin Mobs that drop no experience are ignored for this advancement.	adventure/kill_mob_near_sculk_catalyst
	Monsters Hunted	Kill one of every hostile monster	Monster Hunter	Kill each of these 36 mobs: Blaze Bogged Breeze Cave Spider Creeper Drowned Elder Guardian Ender Dragon Enderman Endermite Evoker Ghast Guardian Hoglin Husk Magma Cube Phantom Piglin Piglin Brute Pillager Ravager Shulker Silverfish Skeleton Slime Spider Stray Vex Vindicator Witch Wither Wither Skeleton Zoglin Zombie Zombie Villager Zombified Piglin Other mobs may be killed, but are ignored for this advancement. Only the riders of the chicken jockeys and skeleton horsemen are counted in this advancement.	adventure/kill_all_mobs

Video[]

History[]

Java Edition Alpha
v1.0.11					Added slimes.
					Slimes are the fifth hostile mob added to the game.
					There are three sizes of slimes: small, medium, and big. Their exact size values in comparison to modern slimes is unknown.
					If slimes are dealt more damage than they have remaining health, they do not split or drop slimeballs.
v1.0.12					Big slimes no longer spawn in Peaceful.
					Slimes now have sound effects.
					The targeting and attacking of slimes has been fixed.
v1.0.13					The texture of slimes has been changed.
v1.0.14					Slime spawning has been reduced as they now appear in abundance.
					A miscalculation in the new limit has now caused slimes to spawn only in strange locations, so natural slime spawning has been disabled.
v1.0.17					Slimes now spawn in multiplayer.
v1.2.0					Slime spawning has been completely disabled.
Java Edition Beta
1.2_01					Slimes have been returned to the game.
					Small slimes now drop 0 - 2 slimeballs.[4]
					Slimes are currently rare.
1.3					Slimes have now become more common.
1.4					A multiplayer bug has been fixed where slimes split were visible only to the player that caused them to split and would not take any damage.[5] Because these slimes were client-side, the player could remove them only by exiting and logging back into the server.
1.5					Slimes no longer spawn in Peaceful difficulty and attack only when provoked.
Java Edition
1.0.0		Beta 1.9 Prerelease 5			Slimes now spawn on levels 0-39 rather than 0-16, making them much more common.
1.1		11w49a			Added slime spawn egg, allowing the player to spawn slimes.
1.3.1		12w15a			The slime spawning rate in superflat worlds has been decreased.
		12w25a			The slime spawning rate in superflat worlds has been decreased, even more.
1.4.2		12w38a			Slimes now have a new mob sound, the same as magma cubes, to make the sounds more realistic.
		12w40a			Slimes are now easier to find as they spawn in swamp biomes at low light level. Since slimes can't swim, it is quite likely that they jump in deep water and eventually drown.
1.5		13w10a			Slime spawn rates in swamps now depend on the current moon phase.
1.7.2		?			Huge slimes can now spawn while summoning with a command block.
1.8		14w06b			Slimes can now swim as a result of the update to the new AI.
					Slimes now randomly change direction every so often, reducing the chance of them getting stuck in walls or corners.
					Slimes now randomly despawn over time if no player is within a 32 block range.
					The jumping mechanics of slimes have been changed. The distance they are able to jump corresponds to their size; they jump approximately the same distance as the length they are. They also turn and face their whole body to the player while attacking.
1.11		16w32a			The entity ID for slimes has been changed from Slime to slime.
1.14		18w43a			The texture of slimes has been changed.
1.16		20w06a			Small slimes now make sounds again when moving.[6]
1.17		21w10a			The maximum size of slimes is now 127.
1.20		23w18a			Slimes are now affected by the Jump Boost effect.[7]
1.20.2		23w33a			The sounds of slimes are now controlled by the "Hostile Creatures" instead of the "Friendly Creatures" sound slider.[8]
Pocket Edition Alpha
v0.9.0		build 1			Added slimes and slime spawn eggs.
		build 2			Slimes now have sounds.
					Slimes now spawn naturally.
v0.10.0		build 1			Slimes now have bouncing animations.
v0.12.1		build 1			Slimes now have particles when jumping.
					Slimes now drop slimeballs.[verify]
v0.13.0		build 3			The spawning of slimes has been improved.
Bedrock Edition
?					Slimes spawn commonly in flat worlds.
1.10.0		beta 1.10.0.3			The texture of slimes has been changed.
1.16.201					Slimes no longer spawn naturally on [flat] worlds.
Legacy Console Edition
TU1	CU1	1.0	Patch 1	1.0.1	Added slimes.
TU14		1.04			The slime spawning rate in superflat worlds has been decreased.
New Nintendo 3DS Edition
0.1.0					Added slimes.

Issues[]

Issues relating to "Slime" are maintained on the bug tracker. Report issues there.

Trivia[]

• In Java Edition, with commands, the size of slimes can be customized. Sizes go from 1 up to 127; the size-127 slime is the largest of any mob in the game, bigger than the ender dragon.
• Because a slime's movement speed is tied to its size it becomes impossible for the player to outrun a size 8 slime on flat ground without potion effects.
• When a slime searches for nearby targets or checks to see if it should despawn, it checks from a point at the center of its hitbox on the x and z-axis and the bottom of its y-axis. Therefore, a custom-size slime sufficiently huge can be right in front of the player and be completely passive, and it may even despawn if the slime is large enough.
• The slime is the most effecient source of exp without farms, easy to kill, high spawn rates in swamps and slime chunks, and deal super low damage to you with armor.

• Green-colored Slimes are also present in Minicraft, a 2D Minecraft-inspired game also created by Notch.
• If a player walks inside a slime, they can see the slime itself inside of a slime block.
• if the player looks at the corner of a glass block, the slime inside the slime block disappears, looking like the slime block is alive.

Gallery[]

Screenshots[]

• 

  Small: 0.6 block cube.

• 

  Medium: 1.2 block cube.

• 

  Big: 2.4 block cube.

• 

  Slimes of various sizes underground.

• 

  A big slime covering a minecart.

• 

  A group of slimes within a Superflat world.

• 

  A group of slimes within a village.

• 

  A group of slimes within a swamp.

• 

  The largest possible slime size: size 127.

• 

  A size 10 slime compared to an oak tree.

• 

  A group of slimes within a cave.

• 

  A group of three slimes are led out of a cave onto the surface.

• 

  A slime within pocket edition alpha.

In other media[]

• 

  A group of slimes within the promotional artwork for the first Caves & Cliffs update.

• 

  A slime within Minecraft Dungeons.

• 

  Prison Slimes, a slime variant that can be found within Minecraft Story Mode Season 2.

• 

  A Slime Spirit within Super Smash Bros. Ultimate.

• 

  A LEGO slime.

• 

  "Frogs," an official T-Shirt design featuring two slimes.

See also[]

• Magma Cube – A similar mob that spawns only in the Nether and drops magma cream
• Tropical Slime - A variant that is found in Minecraft Earth

References[]