MINCRAFT JAVA EDITION 1.21.5 [ MINCRAFT

MINCRAFT JAVA EDITION 1.21.5 RELEASED

Minecraft Java 1.21.5 Released

It's time to experience new wonders of the Overworld as we release the Spring to Life drop, the first Minecraft game drop of 2025.

The Spring to Life drop brings more reasons to explore both near and far! Warm winds have swept across biomes, bringing new mob variants, ambient sounds, and lush plants for you to discover. Befriend fluffy pigs, marvel at glittering firefly bushes, listen out for whispers of sand, and delight in a blooming Overworld humming with new beginnings.

New Features

Added cold and warm variants for the Pig, Cow and Chicken

Sheep now spawn with wool color dependent on the biome in which they spawn

Added new sound variants for Wolves

Overhauled the visuals of each Spawn Egg to improve readability and accessibility

Added fallen tree generation

Added Firefly Bush block

Added Leaf Litter block

Added Wildflowers block

Added Bush block

Added Short Dry Grass and Tall Dry Grass blocks

Added Cactus Flower block which can grow on Cactus blocks

Added new falling leaf particles to all Leaves blocks that did not already have them

Added new ambient block sounds in the Desert and Badlands biomes

Added language support for Kyrgyz

FARM ANIMAL VARIANTS

The cow, the chicken, and the pig are joined by their new variations high up on a mountain. Click here for a link to the full-size image.

Warm and cold variants have been added for the following animals:

Pig

Cow

Chicken

Warm pigs are amongst cactus flowers in a desert

The variant is determined by the biome they spawn in

Temperate variant - The variants we are all familiar with, spawns by default where the other variants do not

Cold variant - A variant that will be selected if spawned (naturally or by player) in these biomes:

Cold Ocean

Deep Cold Ocean

Deep Dark

Deep Frozen Ocean

End Barrens

End Highlands

End Midlands

Frozen Ocean

Frozen Peaks

Frozen River

Grove

Ice Spikes

Jagged Peaks

Old Growth Pine Taiga

Old Growth Spruce Taiga

Small End Islands

Snowy Beach

Snowy Plains

Snowy Slopes

Snowy Taiga

Stony Peaks

Taiga

The End

Windswept Forest

Windswept Gravelly Hills

Windswept Hills

A cold chicken can be seen in the forefront, with a creeper peaking out from behind a tree.

Warm variant - A variant that will be selected if spawned (naturally or by player) in these biomes:

Badlands

Bamboo Jungle

Basalt Deltas

Crimson Forest

Deep Lukewarm Ocean

Desert

Eroded Badlands

Jungle

Lukewarm Ocean

Mangrove Swamp

Nether Wastes

Savanna

Savanna Plateau

Soul Sand Valley

Sparse Jungle

Warm Ocean

Warped Forest

Windswept Savanna

Wooded Badlands

A warm chicken in a desert village. A cat can be seen sitting on top of a villager's house.

When bred by a player, a baby variant will not be chosen by the current biome, but instead randomly selected from one of the parents' variants

Two new Egg items have been added for the warm and cold Chicken variants

Blue Egg - The Egg that is laid by and can hatch cold Chicken variants

Brown Egg - The Egg that is laid by and can hatch warm Chicken variants

Sheep Wool Color in Warm and Cold Biomes

Sheep now spawn with wool color dependent on the biome in which they spawn:

Temperate biomes: (these colors are unchanged from previous behavior)

Common Sheep color is white

Uncommon Sheep colors are black, gray, light gray and brown

There is a rare chance for a pink Sheep to spawn

Cold biomes:

Common Sheep color is black

Uncommon Sheep colors are gray, light gray, white and brown

There is a rare chance for a pink Sheep to spawn

Warm biomes:

Common Sheep color is brown

Uncommon Sheep colors are gray, light gray, white and black

There is a rare chance for a pink Sheep to spawn

Wolf Sounds Variants

A wolf walking on top of a fallen oak tree.

Added 6 new Wolf sound variants with unique ambient, hurt, death, growl, whine, and pant sounds

The new sounds are part of variants that are called "Big", "Cute", "Puglin", "Angry", "Grumpy", and "Sad"

The original Wolf sounds now are used for the variant called "Classic"

Every Wolf will have a sound variant randomly assigned to it from these 7 variants

The sound variant is not related to the texture variant

Spawn Egg Visuals Overhaul

Sunny and Noor are inspecting a collection of spawn eggs. A cartographer villager can also been seen peaking in through the window

Each Spawn Egg now has their own unique visual which captures the personality and character of the mob it spawns

Each egg visual varies in shape to reflect the in-world size of the mob it spawns

For example, smaller mobs tend to have a smaller Spawn Egg

Fallen Trees

A fallen birch tree with a brown mushroom growing on top of it.

Fallen trees are a new decorative variant of trees

Fallen trees come in four different wood type variants:

Oak

Birch

Jungle

Spruce

Birch fallen trees come in a shorter and a longer version

Some fallen trees can be decorated with Mushrooms or Vines

Fallen trees can be found in all biomes where their standing tree variant grows, except the following:

Bamboo Jungle

Flower Forest (has fallen Birch trees but not fallen Oak trees)

Grove

Meadow

River

Firefly Bush

In the moonlit swamp, firefly bushes can be seen emitting particles. Meanwhile, a frog seems to be leaping towards the moon

The Firefly Bush is found adjacent to water in Swamps, Mangrove Swamps, Badlands, and near Rivers

When it is dark, glowing firefly particles appear around the Firefly Bush

Using Bone Meal on a Firefly Bush grows a Firefly Bush in a random adjacent space if possible

The Firefly Bush emits a light level of 2

The Firefly Bush has a chance of playing ambient sounds when these conditions are met:

it is night

it is not blocked from above by any collidable block except leaves

Leaf Litter

Leaf Litter is a new type of decorative block which can be found in the Forests, Dark Forests and Wooded Badlands

Note: Leaf Litter is only spawned as part of world generation, and does not regenerate during gameplay

Leaf Litter can have different amounts of leaves in one block space

Up to four Leaf Litter pieces can be placed in the same block space

Placing a Leaf Litter into an existing Leaf Litter block increases the amount of leaves

Leaf Litter can be placed in four orientations

Leaf Litter can be placed on any block with a full top face

Leaf Litter can be created by smelting any type of Leaves block

Leaf Litter can be used as fuel for smelting

Leaf Litter can be used in the Composter

Leaf Litter has unique block sounds

Leaf Litter is tinted based on which biome it is in

Leaf Litter is replaceable when building

Wildflowers

Wildflowers are a new type of flower which grow in Birch Forests, Old Growth Birch Forests and Meadows

Wildflowers can have different amounts of flowers in one block space

Up to four Wildflowers can be placed in the same block space

Placing a Wildflower into an existing Wildflowers block increases the amount of flowers

Using Bone Meal on Wildflowers will produce more Wildflowers

Wildflowers can be placed in four orientations

Wildflowers can be crafted into Yellow Dye

Bush

The Bush is a new type of decorative block that can be found in small patches in the following biomes:

Birch Forest

Forest

Frozen River

Old Growth Birch Forest

Plains

River

Windswept Forest

Windswept Gravelly Hills

Windswept Hills

The Bush can be used in the Composter

Using Bone Meal on a Bush grows a Bush in a random adjacent space if possible

A Bush only drops when broken with Shears or a Silk Touch tool

The Bush is replaceable when building

Short and Tall Dry Grass

Added two new types of grass: Short Dry Grass and Tall Dry Grass

Both are 1 block high, which means Tall Dry Grass differs from regular Tall Grass which is 2 blocks high

Both generate in the Desert and Badlands biomes

Both can be placed on types of Sand, Terracotta, Dirt blocks, and Farmland like the Dead Bush

Both can be bonemealed

Using Bone Meal on Short Dry Grass grows it into a Tall Dry Grass

Using Bone Meal on Tall Dry Grass grows a Short Dry Grass in a random adjacent space if possible

Both can be used in the Composter

Sheep can eat both to regrow their wool

Both can be used as fuel for smelting

Both are replaceable when building

Cactus Flower

Cactus Flower is a new type of flower that has a chance of generating on Cactuses in Deserts and Badlands

Cactus Flower can be placed on Cactus blocks, Farmland, or any block which has center support at the top of the block

Cactus Flowers have a chance of growing on Cactus blocks instead of the Cactus growing taller

If a Cactus is 1-2 blocks tall, the Cactus Flower has a 10% chance to grow

If a Cactus is 3 blocks or taller the Cactus Flower has a 25% chance to grow

Cactus Flowers will only grow if they have space on all four sides

Cactus Flowers can be used in the Composter

A Cactus Flower can be used to craft 1 Pink Dye

Falling Leaf Particles

All Leaves blocks now have chance of spawning falling leaf particles

The following blocks are affected by this change:

Acacia Leaves

Azalea Leaves

Birch Leaves

Dark Oak Leaves

Flowering Azalea Leaves

Jungle Leaves

Mangrove Leaves

Oak Leaves

Spruce Leaves

New Ambient Sounds for Desert and Badlands

Sand, Red Sand and Terracotta of any color have a chance of playing ambient sounds when surrounded by another block in the same group on at least 3 sides, at a distance of 8 blocks

block.sand.idle can be played in any biome

block.sand.wind only plays when in Desert or Badlands biomes

Dead Bush blocks have a chance of playing ambient sounds when placed on top of two blocks that are any color of Terracotta, Sand or Red Sand blocks in any biome

Changes

The main menu panorama has been updated for the "Spring to Life" drop

Beacons and their beams now render beyond 16 chunks, up to the client render distance

To keep it easily visible at large distances, the beam is rendered thicker the further away you are

The beam now renders up to 2048 blocks high, up from 1024

Three differently colored beacon beams are seen in the sky of a sunset scenery

Lodestones have a new crafting recipe and can now be found in Ruined Portals

The trades of the Cartographer and Wandering Trader have been updated

Bundles can now be found in some of the Chests in Villages

Updates to Camel, Chicken, Cow, Pig, and Sheep spawning

Zombified Piglins now need to be killed by a Player to drop the Player-specific loot such as experience

This makes them consistent with all other mobs in the game

Changes to world generation of the Pale Garden and Meadow biomes

Chunks loaded by a portal will now be re-loaded again automatically when the world is reopened

Improved how simulation distance affects block ticks

Tweaks to the Creaking and Creaking Heart

Textures and models for temperate Cow, Mooshrooms and Sheep have been updated

Minor tweaks to existing Blocks, Items and Entities

Various changes and tweaks to sounds

Minor improvements to world uploads in Realms

Reverted fix MC-152728 - "The player continues sprinting when performing actions that slow them down"

Developer's Note: After consideration, we have decided to revert this fix. While we do want to revisit these mechanics in the future, it's clear that these recent fixes alone didn't quite hit the mark and caused too many negative side effects for parkour, speedbridging, and movement in general

If the game detects that the last startup did not complete normally, the fullscreen option will now be reset

Removed Herobrine

Lodestone Changes

The Lodestone is now crafted from 1 Iron Ingot surrounded by 8 Chiseled Stone Bricks

Lodestones can now be found as loot at Ruined Portals in the Overworld or Nether

Advancement "Country Lode, Take me Home" has been moved from the "Nether" category to the "Adventure" category

Cartographer and Wandering Trader Trade Rebalance

Cartographer Trades

Cartographers now sell 7 new maps each pointing to a different village or other structures in a different biome

Cartographers from different village types will sell a different range of maps and colored banners

Some prices and quantities have also been adjusted

Wandering Trader Trades

The Wandering Trader now has better prices, more trades and a larger amount of stock for many items

They will also now buy basic supplies from players, so it is possible to get some Emeralds by helping them prepare for their next journey - even if you don't feel like buying anything

The Wandering Trader will offer to buy two items from this list:

Water Bottle

Water Bucket

Milk Bucket

Fermented Spider Eye

Baked Potato

Hay Bale

Wandering Traders now have a chance of selling these items (in addition to their previous trades):

Logs (Acacia, Birch, Dark Oak, Jungle, Oak, Spruce, Pale Oak or Cherry)

Enchanted Iron Pickaxe

Potion of Invisibility

Mob Spawning Changes

Camels now spawn in Deserts

Chickens, Cows, Pigs, and Sheep can now spawn in Badlands

World Generation Changes

The Pale Garden biome now occupies more space that was previously taken by Dark Forest

Woodland Mansions can now generate in the Pale Garden biome

Short Grass now generates slightly sparser in Meadows

Simulation Distance

Any block in simulation distance of a player, or loaded by another source of chunk loading such as Ender Pearls, may now receive random ticks instead of 8 chunks just around players

For example: if a chunk is loaded by an Ender Pearl or is in the spawn chunks, crops are able to grow, Ice can melt, Snow can fall, and a Cauldron can be filled by rain

Mob spawning, Lava spreading fire, and Lightning strikes still occur in the previous radius of 8 chunks around players

Fire will no longer burn or spread if no player is within 8 chunks

Creaking and Creaking Heart

Creakings can now be named using Name Tags

Named Creakings will persist through the day

However, they will still be torn down if stuck with a player or if too far from their Heart

Named Creakings are still resistant to all damage, and can communicate with their Hearts via particles

Creaking Hearts correctly placed between Logs have a new dormant texture during the day

Dormant Creaking Hearts cannot spawn new Creakings or Resin

The transition between the awake and dormant states for Creaking Hearts, as well as the transition of Eye Blossoms is now based on the fixed day time

All these behaviors are no longer affected by weather or dimension brightness

Mob Texture and Model Changes

The look of the temperate Cow has been slightly updated to have an extruded snout

The look of both Mooshroom variants have been slightly updated to have an extruded snout

Sheep's wool undercoat is now also colored when dyed

The Sheep wool texture has been tweaked to remove the stark line at the back

Minor Tweaks to Blocks, Items and Entities

Sheep can now eat Fern blocks

Landing on Powdered Snow with Leather Boots equipped after falling further than 2.5 blocks will now make entities fall through the snow

Jumping or falling less than 2.5 blocks allows the entity to land on top of the snow like before

Saddles equipped onto Pigs or Striders will now maintain properties such as custom name when dropped

Bubble columns produce less particles and sounds when entities are unaffected by them are inside them

Pale Oak Leaves and Pale Oak Saplings have an updated map color

Improved tooltips for the Crossbow and all container items

Item Tooltips

Crossbows will now show all charged projectiles in their tooltip instead of just the first

All charged projectiles will also add their entire tooltip as a subsection, instead of only Fireworks

All container items with stored contents, such as a Chest picked with Ctrl+Pick Block, will now list the first 4 items in their tooltip just like Shulker Boxes

Sound Changes

The volume of the narrator is now affected by the game's configured volume in the "Voice" category

Added new break, place, step, fall and hit sounds for Iron Blocks, Iron Bars, Iron Trapdoors, Iron Doors and Heavy Weighted Pressure Plates

The breaking sound for the "grass" sound type has been lowered

Blocks that are broken by a Piston now play their breaking sound

Ambient block sounds in Desert, Badlands and Pale Garden which are only used for ambience have been moved from the "Blocks" to the 'Ambient/Environment' category

Realms World Uploads

Uploading a world to Realms will now enable Command Blocks by default

It is now possible to upload Hardcore singleplayer worlds to Realms

Technical Changes

The Data Pack version is now 71

The Resource Pack version is now 55

A new entry point is present in the server jar: net.minecraft.gametest.Main

Automatically starts a server and runs all available game tests

A new command line argument is available for the client: --renderDebugLabels

Adds debug labels to relevant OpenGL objects, making debugging rendering easier for developers

Minor changes to chat network protocol

Game Test Entry Point

This new entry point automatically starts a server, runs all available game test, and then exits.

Options:

--help - Shows usage information

--packs <path> - Set a folder of data packs to include in the world

Any zip file or folder containing a pack.mcmeta file is included

--report <path> - Exports results in a JUnit-like XML report at the given path

--tests <selection> - Specify which tests to run with a selection - a wildcard expression matching namespace test instance IDs

If omitted, or used with an empty ID, all tests will be run

--universe <path> - The path in which the test server world will be created

Any existing folder will be replaced

Default: gametestserver

--verify <boolean> - Enables test verification

Runs the tests specified with test or testNamespace 100 times for each 90-degree rotation step

Default: false

Example usage: java -DbundlerMainClass="net.minecraft.gametest.Main" -jar server.jar --packs mytestpacks

Network Protocol

The clientbound player_chat packet now contains an index increasing for every message sent to the client

The index starts at 0 when logging in (or is reset by configuration phase and the login packet)

For every message, the server should increment this value by 1

If this value updates in an unexpected way, the client will disconnect

As the protocol requires that every chat packet reaches the client in produced order, the goal is to enable faster detection of missed/reordered chat messages for custom server developers

The serverbound chat and chat_command_signed packets now contain a checksum byte along with the "last seen" update

This is a simple hash of the "last seen" signatures which should be reconstructed by the server, allowing quicker detection of desynchronized state

This can be passed as 0 to disable the check, for compatibility with protocol translation

Data Pack Versions 62 through 71

The Game Tests system is now accessible through data packs and for mods

Added new allowFireTicksAwayFromPlayer and tntExplodes Game Rules

All entities can now store custom data

Added a uniform way to define variant selection rules

Wolf Sound, Pig, Cat, Chicken, Cow, and Frog variants are now data-driven

Changes to commands

Structure Blocks in the "Load" mode have a new option: "Strict Placement"

If set to false, the blocks in the placed structure will not trigger block updates, block entity side effects, or shape updates

The game's handling of NBT has been updated to allow "heterogeneous" lists with elements of different types

The object notation used in commands for NBT, text components and inline predicates (a.k.a. SNBT) has been extended

Updated data format of Text Components

Updated many data formats within entities and block entities

Added new item components, and updates to existing components

The control of tooltip behavior has been reworked into a tooltip_display component

Entity variants are now set and queried with components

Updated Entity Predicates to support entity components

Updated Block Predicates to support block entity components

Updated toggle_tooltips loot function to support new tooltip_display component

The potion entity type has been split into splash_potion and lingering_potion

Added saddle equipment slot for entities, driven by the equippable component

Only mobs that normally support saddles will support riding and rendering of the saddle

Items in the saddle slot can apply attribute modifiers as with other equipment

Changes to crafting_transmute, smithing_transform, and smithing_trim recipe types

Trim pattern and trim material items are no longer specified in the trim registries, but instead in the recipes and items respectively

Added fallen_tree feature type and attached_to_logs tree decorator type

The background field in Advancement definitions no longer contains a textures/ prefix and .png suffix

The effects field in Biome definitions has a new subfield, dry_foliage_color, that defines the color used for tinting blocks using dry foliage tinting (Leaf Litter)

Changes to tags

Added firefly and tinted_leaves particles

Game Tests

Kai is seen testing curious behaviors with the new test blocks

The Game Tests system is a new integrated system for testing aspects of the game. Each test is an asset defining some parameters for how the test gets executed, combined with a saved structure file containing a base setup.

Generally, the test framework expects to run tests in a separate superflat world.

Test Instances

A game test is running, where a villagers is seen running through a maze to get to their bed

Test instances are defined in the registry test_instance. They're small assets defining a test to run.

Fields:

environment: Namespaced ID of the test environment to run this test as part of

structure: The namespaced ID of the structure to use for the test

max_ticks: A positive integer representing the maximum number of ticks allowed to pass before the test is considered timed out

setup_ticks: Optional non-negative integer (default: 0) representing a number of ticks to wait after placing the structure before starting the test

required: Optional boolean (default true) - whether the test is considered required to pass for the full test suite to pass

rotation: Optional rotation to apply to the test structure

One of none (default), clockwise_90, 180 and counterclockwise_90

manual_only: Optional boolean (default false), set to true for tests that are not included as part of automated test runs

sky_access: Whether the test needs clear access to the sky

By default (false), tests are enclosed in barrier blocks - if set to true, the top is left open

max_attempts: Number of attempts to run the test (default 1)

required_successes: Number of attempts that must succeed for the test to be considered successful (default 1)

type: The type of test - one of block_based and function

Function Tests

Function tests rely on built-in functions to run a test and indicate success or failure. They have one additional field:

function: The namespaced ID of the Test Function to run

See the "Using the Game Test Framework from Code" changelog section for more information.

Block Based Tests

Block based tests use Test Blocks in the test structure to run the test and indicate success or failure.

Test Environments

Test Environments are a way to group up tests and give them the right preconditions to run. A Test Environment is an asset in the test_environment registry. Each Test Environment definition has a type field that determines its setup:

all_of definitions apply the setup from several sub-definitions in the definitions field

function definitions use mcfunction files as setup and teardown

setup: Optional namespaced ID of the mcfunction to use for setup, if any

teardown: Optional namespaced ID of the mcfunction to use for teardown, if any

game_rules: definitions set any number of game rules

bool_rules: A list of boolean game rules to set and the value to set

int_rules: A list of integer game rules to set and the value to set

Each rule is an object with two fields:

rule: The exact name of the rule to set

value: The value to set

Game rules are reset to their default values after the test environment has completed

weather definitions sets the weather state

weather: The weather to set - one of clear, rain and thunder

time_of_day definitions set a given time of day

time: The time of day to set in number of ticks, as a non-negative integer

The game provides a single, empty Test Environment by default: minecraft:default.

Test Blocks

The Test Block is a block used for implementing a block-based tests. It has four modes:

start: Triggers a redstone pulse when the test starts

log: Logs a message to the log file when powered by redstone

fail: Fails the test when powered by redstone

accept: Completes the test when powered by redstone

Block-based tests are required to have at least one start block and one accept block in the structure.

The test Command

The test command is a new command used to create and run tests.

Syntax:

test clearall [<radius>]

test clearthat

test clearthese

test create <test> [<width>] [<height> <depth>]

test locate <selector>

test resetclosest

test reseetthese

test resetthat

test pos [<variable>]

test run <selector> [<numberOfTimes>] [<untilFailed>] [<rotationSteps>] [<testsPerRow>]

test runclosest [<numberOfTimes>] [<untilFailed>]

test runfailed [<numberOfTimes>] [<untilFailed>] [<rotationSteps>] [<testsPerRow>]

test runmultiple <selector> [<amount>]

test runthat [<numberOfTimes>] [<untilFailed>]

test runthese [<numberOfTimes>] [<untilFailed>]

test stop

test verify <tests>

Parameters:

radius: The radius to clear tests within

test: The namespaced ID of a test

selector: A wildcard-enabled selector for test IDs

Supports * and ? for matching namespaced IDs

If namespace is not supplied, defaults to minecraft

Examples:

*:* - matches all IDs

* - matches everything in the minecraft namespace

custom:folder/*_test_? - matches IDs in the folder folder of the custom namespace, with a prefix followed by _test_ followed by a single valid character

width: The width of the test structure - if omitted, 5 is used

height: The height of the test structure - if omitted, the width is used

depth: The depth of the test structure - if omitted, the width is used

variable: The variable name to include in the copied code snippet

numberOfTimes: The number of times to repeat each test - if omitted, 1 is ued

untilFailed: Boolean (default false) noting that the test should be stopped as soon as one iteration fails

rotationSteps: Number of extra 90 degree steps to apply to the test - if omitted, 0 is used

testsPerRow: Number of tests to place per row in a grid layout - if omitted, 8 is used

test clear*

These subcommands clear the structures and blocks associated with the selected tests.

test create

This subcommand creates a test setup in the current location for the given test, preparing for a structure of the given size. This gives a starting point for creating the structure for the test.

test locate

Attempts to locate the given test. Note that only loaded chunks are searched.

test reset*

These subcommands reset the structures for the selected tests, removing any surrounding barriers and placing the structure in from scratch.

test pos

Shows the local coordinates to the block pointed at in the test. If the optional variable name is specified, this variable name is used in a code fragment obtained by clicking on the coordinates in the output message.

test run*

Runs one or more tests. If multiple tests are run at once, they are placed in a grid and run in parallel, although only up to a certain limit. Beyond that limit, tests are run in rounds where each round completes before any tests from the next round are started.

For each test, loads the given structure and runs the associated test. Each test location will have a beacon beam showcasing the test status.

Gray beacon = in progress

Red = fail (required test)

Orange = fail (optional test)

Green = success

If a test fails, the error is shown on a lectern book and an overlay.

Note that Game Tests are designed to run on standard superflat worlds. The area around each test is replaced with stone when it runs, and the running test is encased in barrier blocks.

test stop

This stops all running tests. Note that gameplay events triggered by tests may still remain.

test verify*

Verifies one or more tests by running multiple instances of the same test.

Test Instance Blocks

To run a test in a world, a Test Instance Block is used. This type of block represents the test as placed in the world and is used to interact with that test, to save the structure, reset or run the test.

Using the test command to run or create a test will also place a Test Instance Block to control that test.

Using the Game Test Framework from Code

The Game Test Framework can also be used from code in a more versatile manner than block-based tests. For this to work, you need to mod the game to add your test functions to the test_function registry (Registries.TEST_FUNCTION).

Hook into some startup method (pre-registry bootstrap) to add your loader - call TestFunctionLoader.registerLoader() with an implementation of TestFunctionLoader. Your implementation can then use the provided register consumer to register test functions with their namespaced IDs. This namespaced ID can then be referenced in a function type Test Instance.

A test function is a Consumer<GameTestHelper>, using that GameTestHelper instance to manipulate the world and make assertions about the state of the resulting world.

The helper can be used to summon mobs, set blocks, query for blocks and entities and assert the state of the test. Most GameTestHelper methods take test-local coordinates, which you can also find using /test pos.

Example code that might go along with a test structure with a locked hopper containing a Cod, pointed into a Furnace:

public void furnaceSmeltsItem(final GameTestHelper helper) {

helper.setBlock(0, 4, 0, Blocks.AIR);

helper.succeedWhen(() -> helper.assertContainerContainsSingle(new BlockPos(0, 0, 0), Items.COOKED_COD));

}

More complicated setups will often use helper.startSequence() to model sequences of events that must happen.

As opposed to block-based tests, function tests failing will often produce more helpful error messages including the location of whatever failed and what was expected at that location.

Game Rules

allowFireTicksAwayFromPlayer

When true, fire and lava can spread fire outside the 8 chunk range of a player

Note: the fire and lava blocks must still be in simulation distance to spread

Default value: false

tntExplodes

When false, TNT will not explode and cannot be ignited

Default value: true

Uniform Variant Selection

Variants that have spawn rules now use a uniform approach for selection

Selection process:

Every variant has a field spawn_conditions that contains a list of entries

Every entry has a condition and an integer priority

Conditions for all variants for given entity type are evaluated for the position that entity is being spawned

Entries with a priority lower than the maximum priority of remaining entries are removed

The game randomly picks one entry out of the remaining ones

If no conditions are remaining, the variant remains unchanged from default for that entity

Entry format:

priority - integer

condition - optional structure

Fields:

type - see below for values

Additional fields are dependent on type

If this field is not present, the condition is always true

Spawn Conditions

minecraft:biome

Checks if entity is spawning in specific biomes

Fields:

biomes - single entry, list or a tag describing biomes

minecraft:moon_brightness

Checks if the current moon brightness is within a certain range

Fields:

range - floating point range (a single number or an object like {"min": 1, "max": 2})

minecraft:structures

Checks if the entity is spawning in specific structures

Fields:

structures - single entry, list or a tag describing structures

Data-driven Mob Variants

Wolf Variants

The fields angry_texture, tame_texture and wild_texture have been grouped in an assets field, and renamed to angry, tame, and wild

Added field spawn_conditions described in uniform variant selection above

Pig Variants

Pig variants can be data-driven by adding entries to data/<namespace>/pig_variant/<id>.json

This feature is experimental

Fields in file:

model - one of: normal, cold

asset_id - namespaced id for this variant asset, resolves to assets/<namespace>/textures/<path>.png

spawn_conditions - field described in uniform variant selection above

Cat Variants

Cat variants can be data-driven by adding entries to data/<namespace>/cat_variant/<id>.json

This feature is experimental

Fields in file:

asset_id - namespaced id for this variant asset, resolves to assets/<namespace>/textures/<path>.png

spawn_conditions - field described in uniform variant selection above

Frog Variants

Frog variants can be data-driven by adding entries to data/<namespace>/frog_variant/<id>.json

This feature is experimental

Fields in file:

asset_id - namespaced id for this variant asset, resolves to assets/<namespace>/textures/<path>.png

spawn_conditions - field described in uniform variant selection above

Cow Variants

Cow variants can be data-driven by adding entries to data/<namespace>/cow_variant/<id>.json

This feature is experimental

Fields in file:

model - one of: normal, cold, warm

asset_id - namespaced id for this variant asset, resolves to assets/<namespace>/textures/<path>.png

spawn_conditions - field described in uniform variant selection above

Chicken Variants

Chicken variants can be data-driven by adding entries to data/<namespace>/chicken_variant/<id>.json

This feature is experimental

Fields in file:

model - one of: normal, cold

asset_id - namespaced id for this variant asset, resolves to assets/<namespace>/textures/<path>.png

spawn_conditions - field described in uniform variant selection above

Wolf Sound Variants

Wolf sound variants can be data-driven by adding entries to data/<namespace>/wolf_sound_variant/<id>.json

The file contains the following fields which correspond to sound events to use for the specific behaviour:

ambient_sound

death_sound

growl_sound

hurt_sound

pant_sound

whine_sound

Commands

SNBT literals now accept heterogeneous lists

/data can now create and modify heterogeneous lists transparently

The /setblock, /fill, /clone, and /place commands now support a "strict" placement mode

/setblock and /fill have updated handling of block entities

The horse.saddle item slot has been renamed to saddle, and now supports any entity that can equip a Saddle

Text Components in commands such as /tellraw or /title are now specified with SNBT instead of JSON

Text Style in the /scoreboard command when specifying the styled number format is also now specified with SNBT instead of JSON

Text Component arguments in /bossbar, /scoreboard and /team commands are now resolved before use (in the context of entity the held in @s)

Changes to /setblock, /fill, /clone, and /place

The behavior of setblock and fill commands have changed in how they handle block entity data:

If the block entity data is not specified, and the existing block has data, the block entity data will be preserved

If the block entity data is specified, the block entity data will be set to that specified value

To clear block entity data explicitly, you must now specify the block entity data as {}

The operation is now successful if either the block state changed or the block entity data changed

fill, clone, setblock and place template accept a new option: strict

If specified, the command will place blocks as-is without triggering block updates or shape updates

The replace option in the fill command is no longer terminal, and can be followed with additional options

New syntax for commands to use the new strict option, and more flexible use of replace:

fill <from> <to> <block> keep

fill <from> <to> <block> [replace <filter>]? [strict|destroy|hollow|outline]?

clone [from <sourceDimension>]? <begin> <end> [to <targetDimension>]? <destination> [strict]? [[replace|masked|filtered <filter>] [force|move|normal]?]?

setblock <pos> <block> [destroy|keep|replace|strict]?

place template <template> [<pos> [<rotation> [<mirror> [<integrity> [<seed> [strict]?]?]?]?]?]?

NBT Changes

Any interface with NBT data within the game (SNBT representation, /data) now supports heterogeneous lists, i.e. ones where elements are not of the same type

Inserting or replacing into a list of a different type with /data will no longer give an error

Inserting into an array type (e.g. [I;1,2,3]) is still type-restricted

This means that the "wrapper" objects previously used to represent heterogeneous lists will no longer be observable by in-game means

/data can no longer traverse paths with an empty key (e.g. /data get ... foo.''.bar)

The NBT file format is unchanged:

Heterogeneous lists are transformed before storage to bypass NBT constraints

Example transform: ['a', {'b':3}] is stored as [{'':'a'},{'b':3}]

Existing external tools will still be able to read NBT files as before, but heterogeneous lists will be displayed in the transformed form

No data produced by the game has changed: objects such as Text Components were already producing heterogeneous lists in this form

Note: these wrapper objects may never be observed in-game, they are only relevant to developers working with the NBT file or network format directly

SNBT Changes

The text format for describing object-like data in commands (like NBT, text components, predicates, etc.) has been extended

To simplify input of data and macro use, SNBT now also supports following operations:

bool(arg) - converts argument to boolean

if argument is a boolean value, returns value directly

if argument is a number value, returns true if it is non-zero

uuid(str) - converts string representation of UUID to integer array

Number Format

Either whole or fraction parts of a float number can be omitted

Examples: .1 and 1. are valid now

Float numbers now use E notation

Example: both 1.2e3 and 1.2E3, 1.2E+3, 12000e-1 are now a valid way to represent 1200.0

Integer numbers can now be prefixed with 0x to represent hexadecimal numbers and 0b to represent binary numbers

Example: 0xbad (equal to 2989), 0xCAFE (equal to 51966), 0b101 (equal to 5)

Non-zero integer numbers now can't start with 0

Normally it would mean number is in base-8, but we are restricting it to avoid accidental use

Numbers can now contain _ character between sequences of digits (but not at the start or the end of sequence)

Example: 0b10_01, 0xAB_CD, 1_2.3_4__5f, 1_2e3_4

NaN, Inf or hexadecimal float representation are NOT supported

Implicit infinite float values (like 1e1000) are rejected

Type suffixes have been extended:

Integer type suffixes (b or B - byte, s or S - short, i or I - integer, l or L - long) can now be prefixed with s (signed) or u unsigned

New suffixes only affect the valid range when parsing - values are still stored as signed

Example: 240ub is equal to -16sb, while 240sb does not parse

When a suffix is used without u or s, it defaults to signed for decimal numbers and unsigned for binary and hexadecimal numbers

Note: since b is also a valid hexadecimal digit, byte sized hexadecimal values can only be written with a signed suffix, like 0x11ub or 0x11sb

Strings

Quoted strings can now use escape sequences beyond ', " and \:

Unicode escapes:

\x - two digit escape, like \x42

\u - four digit escape, like \u2603

\U - eight digit escape, like \U00002603

\N{<name>} - named Unicode character, like \N{Snowman}

Built-in escape sequences:

\b - backspace, Unicode \x08

\s - space, Unicode \x20

\t - horizontal tab, Unicode \x09

\n - linefeed, Unicode \u0a

\f - form feed, Unicode \u0c

\r - carriage return, Unicode \u0d

Unquoted strings now can't start with 0-9, ., +, - to avoid accidental collision with numbers

Number Arrays

Values in arrays ([B;], [I;], [L;]) without a suffix are now assumed to have suffix matching the type of the array

Example: [B;1,2] is equivalent to [B; 1b, 2b]

Arrays can now also accept types smaller than the array type

Example: [I;1b,2s,3] is valid and equivalent to [I;1i,2i,3i]

Lists

Lists now accept trailing commas

Example: [1,2,] is valid and equivalent to [1,2]

Only one trailing comma is allowed, and it must come after a valid element - both [,] and [1,,] are invalid

Compounds

Compounds (maps) now accept trailing commas

Example: {a:b,}

Only one trailing comma is allowed, and it must come after a valid key-value pair - both {,} and {a:b,,} are invalid

Text Component Data Format

Text Components are no longer stored as JSON wrapped by a string

The format itself is the same as before, but inlined directly into the outer structure

For example, the item component minecraft:custom_name="{"text":"Renamed item"}" will become minecraft:custom_name={text:'Renamed item'}

This includes Text Components passed as arguments to commands such as /tellraw or /title

For example, /tellraw @s {"text":"Hello world"} may become /tellraw @s {text:'Hello world'}

Note: in the case where Text Components are embedded in NBT, no distinction exists between boolean and integer types

To pass boolean arguments to translations, you must use the string form

For Text Components with the nbt type and interpret set to true, Text Components will be parsed from the given NBT directly rather than converting to a string and parsing as JSON

The format of hover and click events has been updated

Hover Events

The hoverEvent field has been renamed to hover_event

The legacy value field (which was parsed from a rendered text component) is no longer supported

For the show_text action:

The contents field has been renamed to value

e.g. {action:'show_text',contents:'Hello world'} becomes {action:'show_text',value:'Hello world'}

For the show_item action:

The contents field has been inlined

e.g. {action:'show_item',contents:{id:'minecraft:stick',count:2}} becomes {action:'show_item',id:'minecraft:stick',count:2}

If contents was specified only as an item id, it is replaced with the full format and inlined

e.g. {action:'show_item',contents:'minecraft:stick'} becomes {action:'show_item',id:'minecraft:stick'}

For the show_entity action:

The contents field has been inlined

The id field has been renamed to uuid

The type field has been renamed to id

e.g. {action:'show_entity',contents:{id:[I;0,0,0,0],type:'minecraft:pig'}} becomes {action:'show_entity',uuid:[I;0,0,0,0],id:'minecraft:pig'}

Click Events

The clickEvent field has been renamed to click_event

For the open_url action:

The value field has been renamed to url

The click event will no longer parse if not a valid URI with either https:// or http:// schemes, instead of simply not working

e.g. {action:'open_url',value:'https://minecraft.net'} becomes {action:'open_url',url:'https://minecraft.net'}

For the run_command action:

The value field has been renamed to command

The click event will no longer parse if the command contains disallowed characters, instead of simply not working

It is no longer required that the specified command field has a / prefix

e.g. {action:'run_command',value:'/tp @e @s'} becomes {action:'run_command',command:'/tp @e @s'}

For the suggest_command action:

The value field has been renamed to command

The click event will no longer parse if the command contains disallowed characters, instead of simply not working

e.g. {action:'suggest_command',value:'/help'} becomes {action:'suggest_command',command:'/help'}

For the change_page action:

The value field has been renamed to page

The page value now requires a positive integer instead of a string

e.g. {action:'change_page',value:'1'} becomes {action:'change_page',page:1}

The copy_to_clipboard format is unchanged

Entity Data

Custom data (previously present only on Marker) is now available on all entities

It's exposed as a minecraft:custom_data component, so it can be set by spawning items and matched by predicates

The component is currently stored in a field called data, which will be changed in the future when more proper storage for entity components is introduced

It's stored only if it's non-empty

Updated and unified formats for storing equipment-related data on entities

The Owner field of tamed animals is no longer restricted to referencing Players

The Health and Air fields now default to their respective maximum value if not specified

The Tags and FallFlying fields will no longer be preserved if removed

The FallDistance field has been changed from float to double and is now called fall_distance

The SleepingX, SleepingY, and SleepingZ fields have been collected into a single sleeping_pos field

Pos, Motion, and Rotation values without the correct number of components (3, 3, and 2 respectively) will now be fully discarded, instead of only selecting the specified components

e.g. sleeping_pos: [I;1,2,3]

Block States in the entity data of Arrows, Minecarts, Block Displays, Endermen, Falling Blocks, Primed TNT, or Piston Moving Blocks are no longer allowed to be specified as an empty object

Many tweaks to entity data formats of specific entities

Equipment Data

The ArmorItems, HandItems, and body_armor_item fields have been merged into an equipment field

Format: map between equipment slot type and item stack

Valid equipment slots: head, chest, legs, feet, mainhand, offhand, body, saddle

If not specified or removed, the entity will have no equipment

e.g. equipment:{chest:{id:'minecraft:diamond_chestplate'}}

This affects all mobs and Armor Stands

The armor and off-hand equipment of Players is now also stored in the equipment field (although items written into the Inventory using armor and off-hand slot numbers still work)

The data format of saddles has been unified between mobs such as Horses and Pigs, becoming a new kind of equipment slot (and stored in the equipment.saddle field)

This is a pure rename from the previous SaddleItem in Horse-like mobs

This also replaces the boolean Saddle flag from Pigs and Striders

The Saddle dropping on death is now affected by the drop_chances field, as with other equipment slots

The ArmorDropChances, HandDropChances, and body_armor_drop_chance fields have been merged into a drop_chances field

Format: map between equipment slot type and chance value

If not specified or removed, chances will be assumed as default (0.085f)

e.g. drop_chances:{chest:0.1,feet:1.0}

Drop chances with a default value will no longer be stored, and the drop_chances field is removed entirely if all defaults

allay

Removed redundant CanDuplicate field (controlled by DuplicationCooldown)

area_effect_cloud

Area Effect Clouds have a new field: potion_duration_scale (float)

If not specified, defaults to 1.0

The duration of the potion effect applied is scaled by this factor

Area Effect Clouds created by Lingering Potions will have a scale of 0.25

The Duration field now defaults to -1 if not specified

If the Duration field is -1, the Area Effect Cloud will never run out

This means that an Area Effect Cloud summoned with no duration specified will no longer immediately disappear

cat

The CollarColor field now defaults to 14 (red) if not specified

creeper

The Fuse field now defaults to 30 if not specified

The ExplosionRadius field now defaults to 3 if not specified

dolphin

Removed TreasurePosX, TreasurePosY, TreasurePosZ fields

The Moistness field now defaults to 2400 if not specified

ender_dragon

The DragonDeathTime field now defaults to 0 if not specified

falling_block

The BlockState field can now be air (will despawn immediately) - if otherwise not specified or invalid, defaults to sand

The HurtEntities field now defaults to false if not specified (or true if BlockState is anvil)

The FallHurtAmount field now defaults to 0 if not specified

The FallHurtMax field now defaults to 40 if not specified

The DropItem field now defaults to true if not specified

The TileEntityData field will no longer be preserved if removed

firework_rocket

The ShotAtAngle field now defaults to false if not specified

fox

The Trusted field now defaults to empty if not specified (and will no longer be merged with the previous state if modified by /data)

ghast

The ExplosionPower field now defaults to 1 if not specified

goat

The HasLeftHorn and HasRightHorn fields now default to true if not specified

interaction

The width and height fields now default to 1 if not specified

item

The Health field now defaults to 5 if not specified

The PickupDelay field now defaults to 0 if not specified

The Age field now defaults to 0 if not specified

The Owner and Thrower fields will no longer be preserved when removed

item_frame and glow_item_frame

The TileX, TileY, and TileZ fields have been collected into a single block_pos field

The ItemDropChance field now defaults to 1.0 if not specified

item

The Owner and Thrower fields will no longer be preserved when removed

phantom

The Size field has been renamed to size

The AX, AY, and AZ fields have been collected into a single anchor_pos field

player

The SpawnX, SpawnY, SpawnZ, SpawnAngle, SpawnDimension, and SpawnForced fields have been collected into a single respawn field

Format: object with fields

pos - block position to spawn at

angle - float, angle to spawn with (default: 0.0)

dimension - dimension id to spawn in (default minecraft:overworld)

forced - boolean, true if this spawn was set through commands (default: false)

The enteredNetherPosition field has been renamed to entered_nether_pos, and is now formatted as a list of doubles

e.g. entered_nether_pos: [1.0, 2.0, 3.0]

primed_tnt

The fuse field now defaults to 80 if not specified

The block_state field now defaults to tnt if not specified

The explosion_power field now defaults to 4 if not specified

shulker

The Color field now defaults to 16 (no color) if not specified

shulker_bullet

The Dir and Target fields will no longer be preserved when removed

skeleton

The StrayConversionTime field will no longer be preserved when removed

spectral_arrow

The Duration field now defaults to 200 if not specified

snow_golem

The Pumpkin field now defaults to true if not specified

tnt_minecart

The fuse field now defaults to 80 if not specified

The explosion_power field now defaults to 4 if not specified

The explosion_speed_factor field now defaults to 1 if not specified

turtle

The HomePosX, HomePosY, and HomePosZ fields have been collected into a single home_pos field

Removed TravelPosX, TravelPosY, and TravelPosZ fields

The HasEgg field has been renamed to has_egg

trader_llama

The DespawnDelay field now defaults to 47999

vex

The LifeTicks field has been renamed to life_ticks

The BoundX, BoundY, and BoundZ fields have been collected into a single bound_pos field

villager

The FoodLevel and Xp fields now default to 0 if not specified

The Gossips and ConversionTime fields will no longer be preserved when removed

wandering_trader

The DespawnDelay field now defaults to 0 if not specified

The wander_target field will no longer be preserved when removed

wolf

The CollarColor field now defaults to 14 (red) if not specified

zombie

The DrownedConversionTime field will no longer be preserved when removed

zombie_villager

The Xp field now defaults to 0 if not specified

The Gossips and ConversionTime fields will no longer be preserved when removed

evoker_fangs, area_effect_cloud, and all projectiles

The Owner field will no longer be preserved when removed

painting and leash_knot

The TileX, TileY, and TileZ fields have been collected into a single block_pos field

arrow, spectral_arrow, trident

The inBlockState and SoundEvent fields will no longer be preserved when removed

The damage field now defaults to 2 if not specified

dragon_fireball, wind_charge, breeze_wind_charge, wither_skull, small_fireball, and large_fireball

The acceleration_power field now defaults to 0.1 if not specified

small_fireball and large_fireball

The ExplosionPower field now defaults to 1 if not specified

minecart, *_minecart

The CustomDisplayTile field has been removed

DisplayState will now always override the default displayed block state if specified

DisplayOffset may now be specified to override the default offset even without a custom display block state set

block_display, item_display, and text_display

The interpolation_duration, teleport_duration, and start_interpolation fields now default to 0 if not specified

The view_range field now defaults to 1 if not specified

The shadow_radius field now defaults to 0 if not specified

The shadow_strength field now defaults to 1 if not specified

The width and height fields now default to 0 if not specified

The glow_color_override field will no longer be preserved when removed

witch, ravager, pillager, illusioner, evoker, and vindicator

The patrol_target field will no longer be preserved when removed

Block Entity Data

The CustomName field will no longer be preserved when removed

The LootTable field will no longer be preserved when removed

campfire

The CookingTimes and CookingTotalTimes fields will no longer be preserved when removed

chiseled_bookshelf

The last_interacted_slot field now defaults to -1 if not specified

end_gateway

The exit_portal field will no longer be preserved when removed

furnace, smoker, blast_furnace

The RecipesUsed field will no longer be preserved when removed

hopper

The TransferCooldown field now default to -1 if not specified

jigsaw

The name, target, and pool fields now default to minecraft:empty if not specified

The final_state field now defaults to minecraft:air if not specified

sculk_shrieker

The warning_level field now defaults to 0 if not specified

skull

The note_block_sound field will no longer be preserved when removed

structure_block

The ignoreEntities and showboundingbox fields now default to true if not specified

The posY field now defaults to 1 if not specified

Data Components

New weapon Item Component

When present, the "Item Used" statistic will be incremented for each attack with the item

The specified amount of damage will be subtracted from the item's durability with each attack

Format: object with fields:

item_damage_per_attack - non-negative integer (default: 1)

The amount of damage to subtract from the weapon item's durability for each attack performed

disable_blocking_for_seconds - non-negative float (default: 0)

If non-zero, will disable a blocking Shield on successful attack for the specified amount of seconds

e.g. weapon={item_damage_per_attack:2}

New blocks_attacks Item Component

When present, this item can be used like a Shield to block attacks to the holding player

Format: object with fields:

block_delay_seconds - non-negative float (default: 0)

The number of seconds that right-click must be held before successfully blocking attacks

disable_cooldown_scale - non-negative float (default: 1)

Multiplier applied to the number of seconds that the item will be on cooldown when attacked by a disabling attack (disable_blocking_for_seconds on the weapon component)

If 0, this item can never be disabled by attacks

damage_reductions - list of objects with fields (optional)

Controls how much damage should be blocked in a given attack

If not specified, all damage is blocked

Each entry in the list contributes an amount of damage to be blocked, optionally filtered by damage type

Each entry adds to blocked damage, determined by clamp(base + factor * dealt_damage, 0, dealt_damage)

The final damage applied in the attack to the entity is determined by dealt_damage - clamp(blocked_damage, 0, dealt_damage)

Entry format:

horizontal_blocking_angle - angle in degrees as a positive float (default: 90)

The maximum angle between the user's facing and the incoming attack for the block to be effective

If the damage has no position, the compared angle will be assumed to be the maximum 180

type - damage type id, list of damage type ids, or hash-prefixed damage type tag (optional)

This entry will only contribute to the blocked damage if the dealt damage type matches this field

If not specified, any damage type will be accepted

base - float

Constant amount of damage to be blocked

factor - float

Fraction of the dealt damage that should be blocked

item_damage - object with fields (optional)

Controls how much damage should be applied to the item from a given attack

If not specified, a point of durability is removed for every point of damage blocked

The final damage applied to the item is determined by: floor(base + factor * damage_blocked)

The final value may be negative, causing the item to be repaired

Format:

threshold - non-negative float

The minimum amount of damage blocked in the attack before item damage is applied to the item

base - float

ConstaTest instances are defined in the registry test_instance. They're small assets defining a test to run.