Java Edition 1.18

1.18, the release of Caves & Cliffs: Part II, is an upcoming major update to  set to release in November or December 2021. It was first announced alongside the release of 1.17 snapshot 21w15a when Mojang Studios stated that the Caves & Cliffs update would be split in two. Some features for 1.18 were initially implemented during 1.17's development cycle, before getting postponed and relegated to official data packs used with a corresponding 1.17 snapshot.

Items

 * Music Disc
 * Added a new music disc from Lena Raine titled "otherside".
 * Can be found on rare occasions in stronghold corridor chests, or much more rarely in dungeon chests.
 * Has a blue and green color to the ring area of the disc.

World generation

 * Caves
 * Completely overhauled.
 * Now stretch down to Y=-59.
 * The caves now generate in 2 layers of different stone bases depending on the depth.
 * The layer above Y=0 is made up of regular stone.
 * Stone transitions to deepslate from Y=0 to Y=-7.
 * Deepslate completely replaces stone from Y=-8 to bedrock.
 * Certain types of ores and structures still generate in the deepslate layer, as well as tuff and gravel.
 * Dirt, diorite, granite and andesite do not generate in this layer.
 * Biomes such as the dripstone caves and lush caves now generate in the underground.
 * Contain aquifers, bodies of water with different heights, independent of sea level (Y=63).
 * Aquifers below Y=0 sometimes generate with lava instead of water.
 * Improved old caves to blend in with the new generations of caves better
 * New noise caves, coming in 3 forms, "cheese", "spaghetti", and "noodle".
 * Cheese caves have large stone towers stretching from the bottom of the cave to the top, and are often large enough to allow safe elytra flight.
 * Spaghetti caves are long, thin caves that have small aquifers and are more similar to original caves.
 * Noodle caves are thinner, squigglier, and more claustrophobic variants of spaghetti caves.


 * Mountains
 * Come in 6 sub-biomes:
 * Meadow
 * A flat but elevated biome that looks like a flowery and colder plains, with an aqua grass color and dark blue water color.
 * Generates in plateaus and the lowest layers of some mountains, usually near plains and other temperate biomes.
 * Contains grass, tall grass, dandelions, azure bluets, cornflowers, poppies, daisies and alliums
 * Birch and oak trees can rarely appear in this biome, and always have bee nests.
 * Only rabbits, donkeys, and sheep spawn in this biome.
 * Plains villages and pillager outposts can generate in this biome.
 * Grove
 * Generates in the slopes of a snowy mountain when next to forested biomes.
 * Reminiscent of a snowy taiga with a surface of snow blocks and powder snow, instead of grass blocks.
 * Rabbits, wolves, foxes, sheep, pigs, chickens and cows spawn in this biome.
 * Pillager outposts can generate in this biome.
 * Snowy Slopes
 * Generates in the slopes of a mountain when next to plains and snowy tundras.
 * Covered in snow, snow block and powder snow.
 * Only rabbits and goats spawn in this biome.
 * Igloos and pillager outposts can generate in this biome.
 * Jagged Peaks
 * One of three biomes that generate in the mountain peaks.
 * Covered in snow, snow blocks and stone.
 * Tends to generate in sharp and jagged peaks in areas with snowy, cold, and temperate biomes.
 * Only goats spawn in this biome.
 * Pillager outposts can generate in this biome.
 * Frozen Peaks
 * One of three biomes that generate in the mountain peaks.
 * Covered in snow, snow blocks, ice, and packed ice.
 * Tends to generate in smoother and smaller peaks in areas with snowy, cold, and temperate biomes.
 * Only goats spawn in this biome.
 * Pillager outposts can generate in this biome.
 * Stony Peaks
 * One of three biomes that generate in the mountain peaks.
 * Covered in stone, gravel, and strips of calcite.
 * Tends to generate in any peak surrounded by warm biomes such as jungles and savannas, to avoid temperature clashes.
 * No animals spawn in this biome.
 * Pillager outposts can generate in this biome.


 * Old worlds upgrading
 * Terrain from new chunks will now blend with existing terrain from old chunks.
 * The old bedrock layer between Y=0 and Y=4 in old chunks gets replaced with deepslate.
 * If there is bedrock at Y=0, lower places in old chunks will be filled with deepslate.
 * Caves do not generate below Y=0 in old chunks but lava lakes and geodes may generate.
 * A new bedrock layer is placed at Y=-64.


 * Ore veins
 * Long and rare ore formations.
 * Copper ore veins mixed with granite and blocks of raw copper generate above Y=0.
 * Iron ore veins mixed with tuff and blocks of raw iron generate below Y=0.

Command format

 * When enabled, begins profiling with Java FlightRecorder, as well as the following custom events:
 * minecraft.ServerTickTime: Sampling event exposing average server tick times in intervals of a second
 * minecraft.ChunkGeneration: Time taken to generate individual chunk stages
 * minecraft.PacketRead / minecraft.PacketSent: Network traffic
 * minecraft.WorldLoadFinishedEvent: Initial world loading duration
 * The profiling can be stopped in-game by using.
 * The profiling can be stopped in-game by using.

Gameplay

 * Advancements
 * Added four new advancements:
 * Caves & Cliffs
 * Fall from the top to the bottom of the Overworld.
 * Feels like home
 * Ride a strider on lava for 50 blocks in the Overworld.
 * Sound of Music
 * Play music with a jukebox in a meadow biome.
 * Star Trader
 * Trade with a villager at the build height limit.
 * Added new advancement triggers.
 * Triggered when a player lands after falling.
 * Triggered for every tick when player rides in lava.
 * Triggered for every tick when player rides in lava.
 * Triggered for every tick when player rides in lava.

General

 * Debug screen
 * Added three new lines: Multinoise, biome builder, and terrain.
 * Only appear if the dimension where the player is uses the multi-noise biome source type.
 * Multinoise lists the parameters used at the player's position in order to place a biome. C is continentalness, E is erosion, T is temperature, H is humidity, and W is weirdness.
 * Continentalness goes up as you go more inland. In areas with low continentalness values, oceans may generate.
 * Erosion determines how flat or mountainous terrain is. Higher values result in flatter areas, lower values result in mountainous areas.
 * Temperature and humidity have no impact on the terrain itself, and only determine biome placement.
 * Weirdness indirectly drives the PV (peaks and valleys) noise and determines which biome variant gets placed.
 * Terrain lists values related to terrain generation.


 * Font
 * Added, the rune-like font from Minecraft Dungeons.
 * Currently only usable via commands


 * Languages
 * Added Lombard.
 * Added Toki Pona.


 * Loot tables
 * Added the field, which is mandatory.
 * Written into to ensure that the tag can be migrated correctly between versions
 * Added new loot table function, to set tag on any item.
 * Has following parameters:
 * : Potion ID


 * Music
 * Added new music to the Overworld (when playing in survival mode), distributed to the new biomes, and to the main menu.
 * By Lena Raine: "Stand Tall", "Left to Bloom", "One More Day", "Wending" and "Infinite Amethyst":
 * "Stand Tall" plays in the snowy slopes, jagged peaks, frozen peaks and stony peaks biomes, as well as the menu screen.
 * "Left to Bloom" plays in the meadow and lush caves biomes, as well as the menu screen.
 * "One More Day" plays in the meadow, snowy slopes and lush caves biomes, as well as the menu screen.
 * "Wending" plays in the grove, jagged peaks, stony peaks and dripstone caves biomes, as well as the menu screen.
 * "Infinite Amethyst" plays in the grove and dripstone caves biomes, as well as the menu screen.
 * By Kumi Tanioka ( 谷岡 久美 ): "Floating Dream", "Comforting Memories" and "An Ordinary Day":
 * "Floating Dream" plays in the jagged peaks and lush caves biomes.
 * "Comforting Memories" plays in the grove biome.
 * "An Ordinary Day" plays in the snowy slopes, dripstone caves and lush caves biomes.


 * NBT tags
 * Spawners now have a new tag, which lets players override the spawn rules of the spawned mob.
 * In the tag, players can specify, which indicates the highest block-light the spawners will spawn mobs at.


 * Options
 * Can now disable lightning flashes, which prevents lightning from making the sky flash. Lightning bolts themselves will still appear.
 * The device the game outputs audio to can now be chosen in-game.
 * Added "Chunk Builder" to video settings.
 * Determines as to which chunk sections are updated synchronously in a single frame.
 * Three options: Threaded, which corresponds to how chunk sections were updated before 21w37a, and Semi Blocking and Fully Blocking, which reduce stuttering when placing or removing blocks. However, the latter two options may cause rare visual delays in world updates.
 * Added "Simulation Distance" video setting, a new slider.
 * Entities will not be updated outside of simulation distance.
 * Allows higher render distance with less CPU load.
 * Added "Autosave Indicator" to video settings, for singleplayer worlds, which allows to toggle the indicator on / off.
 * The indicator appears in the bottom right of the screen whenever the game is saving the world file.
 * Defaults to on.


 * Particles
 * Added, to replace   and.
 * Renders with texture declared in  slot for model assigned to configured block state.
 * Summoned with same syntax as  particle (i.e.  ).


 * server.properties
 * Added.


 * Subtitles
 * Added subtitles for various bundle sounds.
 * Added a new subtitle for the crop sound of shears.


 * Tags
 * Added block tag.
 * Contains farmland and the #dirt and #small dripleaf placeable block tags.
 * Big dripleaf can be placed on blocks in this tag.


 * Telemetry
 * Readded, previously a part of game known as "snooper" until 18w20c.
 * Only implemented in world load event now.
 * Sent data when loading singleplayer world or connecting to multiplayer server.
 * Contains following information:
 * Launcher identifier
 * User identitifer (XUID)
 * Client session ID (changes on restart)
 * World session ID (changes per world load, to be reused for later events)
 * Game version
 * Operating system name and version
 * Java runtime version
 * If client or server is modded (same information as on crash logs)
 * Server type (single player, Realms or other)
 * Game mode
 * Cannot be disabled,

Blocks

 * Big Dripleaf
 * Restricted big dripleaf placement to clay, coarse dirt, dirt, farmland, grass blocks, moss blocks, mycelium, podzol and rooted dirt.


 * Cave Vines, Kelp, Twisting Vines, and Weeping Vines
 * Now stop growing if shears are used on the tip.
 * This action changes the  block state of the tip to 25.


 * Cave Vines
 * Changed cave vines plant texture from to.


 * Copper Ore
 * Now drop 2-5 Raw Copper when mining instead of 2-3.


 * Enchanting Table
 * Now emits a light level of 7.
 * Changed the texture of the lapis icon in the GUI from Lapis Lazuli (enchanting slot) JE1 BE1.png to Lapis Lazuli (enchanting slot) JE2.png.


 * Magma Blocks
 * Slightly increased the frequency of underwater magma.


 * Redstone Comparator
 * Changed the base texture of lit comparators from Powered Redstone Comparator (S) JE4.png Powered Subtracting Redstone Comparator (S) JE5.png to Powered Redstone Comparator (S) JE5.png Powered Subtracting Redstone Comparator (S) JE6.png.


 * Stonecutter
 * Block of Copper can be converted to 4 Cut Copper using stonecutter.

Items

 * Campfire and Soul Campfire
 * Changed the item textures from Campfire (item) JE1 BE1.png Soul Campfire (item) JE1 BE1.png to Campfire (item) JE2.png Soul Campfire (item) JE2.png.


 * Doors
 * Changed the item textures of all doors except crimson and warped from Oak Door (item) JE3 BE2.png Birch Door (item) JE3 BE1.png Spruce Door (item) JE3 BE1.png Jungle Door (item) JE4.png Acacia Door (item) JE3 BE1.png Dark Oak Door (item) JE3 BE1.png Iron Door (item) JE2 BE2.png to Oak Door (item) JE4.png Birch Door (item) JE4.png Spruce Door (item) JE4.png Jungle Door (item) JE5.png Acacia Door (item) JE4.png Dark Oak Door (item) JE4.png Iron Door (item) JE3.png.


 * Item Frames and Glow Item Frames
 * Changed the item textures from Item Frame (item) JE2 BE2.png Glow Item Frame (item) JE1 BE1.png to Item Frame (item) JE3.png Glow Item Frame (item) JE2.png.


 * Signs
 * Changed the item textures from Oak Sign JE2 BE2.png Spruce Sign JE1 BE1.png Birch Sign JE1 BE1.png Jungle Sign JE1 BE1.png Acacia Sign JE1 BE1.png Dark Oak Sign JE1 BE1.png Crimson Sign JE1 BE1.png Warped Sign JE1 BE1.png to Oak Sign JE3.png Spruce Sign JE2.png Birch Sign JE2.png Acacia Sign JE2.png Jungle Sign JE2.png Dark Oak Sign JE2.png Crimson Sign JE2.png Warped Sign JE2.png.

Mobs

 * Axolotls
 * Now only spawn in water above clay blocks in lush caves.
 * Now has its own mob cap.


 * Cod, Salmon, Pufferfish, Tropical Fish, Squid, and Dolphins
 * Now only spawn in water from Y=50 to Y=64.
 * Additionally, tropical fishes now also spawn in lush caves at any height.


 * Drowned
 * Now can spawn in aquifers inside dripstone caves.


 * Evoker, Pillager, Vindicator, and Illusioner


 * Will no longer attack baby villagers.


 * Glow Squids
 * Now only spawn in water blocks under Y=30.


 * Goat
 * Now only spawn in snowy slopes, jagged peaks, and frozen peaks biomes.


 * Horses, mules, and donkeys
 * Now follow players holding golden carrots, golden apples, and enchanted golden apples.


 * Llamas
 * Now follow players holding hay bales.


 * Wither
 * Tweaked the wither skull's texture to use the new wither face from the Texture Update.


 * Zombie Villager
 * Tweaked the armorer zombie villager's and weaponsmith zombie villager's textures to remove stray villager pixels.


 * General
 * Hostile mobs will only spawn in areas where the light level is equal to 0.
 * This change only affects block-light and not sky-light.
 * Optimized AI for Axolotls, Goats, Hoglins, Zoglins, Piglins, Piglin Brutes and Villagers.
 * All feedable mobs (except sheep) named Dinnerbone will now look at the player correctly.

World generation

 * Amethyst Geodes
 * Now only generate up to Y=30.


 * Badlands
 * Now can generate in mountain peaks.
 * Red sand generates a bit higher.
 * Red sandstone now generates naturally once again.


 * Beaches
 * Beaches are generally wider.
 * In some places there is a chance where no beaches generate at all, to provide some variation.


 * Biomes
 * Some biomes have been renamed:
 * {| class="wikitable collapsible collapsed"

! Old name !! New name
 * Tall Birch Forest || Old Growth Birch Forest
 * Giant Tree Taiga || Old Growth Pine Taiga
 * Giant Spruce Taiga || Old Growth Spruce Taiga
 * Snowy Tundra || Snowy Plains
 * Jungle Edge || Sparse Jungle
 * Stone Shore || Stony Shore
 * Extreme Hills || Windswept Hills
 * Wooded Mountains || Windswept Forest
 * Gravelly Hills || Windswept Gravelly Hills
 * Shattered Savanna || Windswept Savanna
 * Wooded Badlands Plateau || Wooded Badlands
 * }
 * Extreme Hills || Windswept Hills
 * Wooded Mountains || Windswept Forest
 * Gravelly Hills || Windswept Gravelly Hills
 * Shattered Savanna || Windswept Savanna
 * Wooded Badlands Plateau || Wooded Badlands
 * }
 * Shattered Savanna || Windswept Savanna
 * Wooded Badlands Plateau || Wooded Badlands
 * }
 * Wooded Badlands Plateau || Wooded Badlands
 * }


 * Since the terrain height is no longer controlled by biomes, most of the height variant sub-biomes, along with previously unused biome variants have been removed from the game and had their code merged into the main biome:
 * {| class="wikitable collapsible collapsed"

! Removed biomes
 * }
 * As a result of this change:
 * All deserts are now eligible for village and desert pyramid generation.
 * All taigas are now eligible for village and outpost generation.
 * All swamps are now eligible for swamp hut generation.
 * All snowy taigas are now eligible for igloo generation.
 * Worlds made in previous versions that generated these biomes will convert them into their default variants.
 * }
 * As a result of this change:
 * All deserts are now eligible for village and desert pyramid generation.
 * All taigas are now eligible for village and outpost generation.
 * All swamps are now eligible for swamp hut generation.
 * All snowy taigas are now eligible for igloo generation.
 * Worlds made in previous versions that generated these biomes will convert them into their default variants.
 * }
 * As a result of this change:
 * All deserts are now eligible for village and desert pyramid generation.
 * All taigas are now eligible for village and outpost generation.
 * All swamps are now eligible for swamp hut generation.
 * All snowy taigas are now eligible for igloo generation.
 * Worlds made in previous versions that generated these biomes will convert them into their default variants.
 * }
 * As a result of this change:
 * All deserts are now eligible for village and desert pyramid generation.
 * All taigas are now eligible for village and outpost generation.
 * All swamps are now eligible for swamp hut generation.
 * All snowy taigas are now eligible for igloo generation.
 * Worlds made in previous versions that generated these biomes will convert them into their default variants.
 * }
 * As a result of this change:
 * All deserts are now eligible for village and desert pyramid generation.
 * All taigas are now eligible for village and outpost generation.
 * All swamps are now eligible for swamp hut generation.
 * All snowy taigas are now eligible for igloo generation.
 * Worlds made in previous versions that generated these biomes will convert them into their default variants.
 * }
 * As a result of this change:
 * All deserts are now eligible for village and desert pyramid generation.
 * All taigas are now eligible for village and outpost generation.
 * All swamps are now eligible for swamp hut generation.
 * All snowy taigas are now eligible for igloo generation.
 * Worlds made in previous versions that generated these biomes will convert them into their default variants.
 * }
 * As a result of this change:
 * All deserts are now eligible for village and desert pyramid generation.
 * All taigas are now eligible for village and outpost generation.
 * All swamps are now eligible for swamp hut generation.
 * All snowy taigas are now eligible for igloo generation.
 * Worlds made in previous versions that generated these biomes will convert them into their default variants.
 * }
 * As a result of this change:
 * All deserts are now eligible for village and desert pyramid generation.
 * All taigas are now eligible for village and outpost generation.
 * All swamps are now eligible for swamp hut generation.
 * All snowy taigas are now eligible for igloo generation.
 * Worlds made in previous versions that generated these biomes will convert them into their default variants.
 * All swamps are now eligible for swamp hut generation.
 * All snowy taigas are now eligible for igloo generation.
 * Worlds made in previous versions that generated these biomes will convert them into their default variants.


 * Buried Treasure
 * Buried treasure chests can now contain water breathing potions.


 * Desert pyramids
 * No longer generate on water.
 * Now spawn on the surface rather than at a fixed y-level, but tend to be partially buried.


 * Dripstone Caves
 * Now generate naturally underground and inside hills or mountains.
 * Drowned can spawn in aquifers inside dripstone caves.


 * Dungeons
 * Increased the amount of dungeons, especially below Y=0.


 * Fossils
 * The fossils in the deepest part of the underground generate with Deepslate Diamond Ore instead of Coal Ore.


 * Jungle pyramids
 * No longer generate on water.


 * Lakes
 * Water lakes were removed, because Aquifers could provide local water levels.


 * Lush Caves
 * Now generate naturally underground and inside hills or mountains.
 * Azalea trees now generate above lush caves.


 * Mineshafts
 * Now generate higher up in badlands.


 * Ore distribution
 * Changed ore generation of all ores making them have a spread value like lapis lazuli ore. Some still retain a linear generation alongside a spread generation.
 * Coal ore attempts to generate twice: once, evenly between an altitude of Y=136 and Y=256; and as a spread, peaking at an altitude of Y=96 and generating between an altitude of Y=0 and Y=192.
 * Copper ore generates between Y=-16 and Y=112, generating the most at Y=48 and like all other ores, uses spread. It peaks at Y=48. Bigger blobs of copper ore generate in dripstone caves.
 * Iron ore attempts to generate three times: once as a spread peaking at an altitude of Y=256, generating above Y=80; another as a spread peaking at Y=16 and generating with a minimum height of Y=-24 and a maximum height of Y=57, and a smaller one spreading evenly between the altitudes of Y=-64 and Y=-32.
 * Gold ore generates between the altitudes of Y=-64 and Y=32, peaking at Y=-16. Also, extra gold generates below Y=-48. The extra gold that generates in the badlands biome was increased, with a top height limit from Y=79 to Y=256, and increased number of blobs.
 * Lapis lazuli ore attempts to generate twice: once, as a spread between the altitudes of Y=32 and Y=-32, peaking at an altitude of 0; and evenly between the altitudes of Y=64 and Y=-64, generating buried like ancient debris.
 * Redstone ore attempts to generate twice: once, evenly between an altitude of Y=15 and Y=-64; and as a spread, peaking at an altitude of -64 and generating below an altitude of Y=-32.
 * Diamond ore now generate as a spread, generating below Y=16 and peaking at altitudes near y=-64.
 * Emerald ore generates above Y=-16 as a spread, peaking at Y=256 and decreasing in quantity as the altitude decreases.


 * Pillager outposts
 * Now generate in all the new mountain biomes.


 * Springs
 * Lava springs can now generate amid calcite, dirt, snow, powder snow and packed ice.
 * These changes allow lava springs to generate in mountains and snowy terrain.
 * Water springs don't generate higher than Y=192, and are less common.


 * Stony Shore
 * Now generate with strips of gravel.
 * Can generate alongside any biome instead of just windswept hills.


 * Villages
 * Now slightly more spread out.
 * Now generate in meadows.


 * General
 * The overworld now uses the multi-noise biome source type.
 * Terrain generation is now independent from biomes, with biomes adapting to whatever terrain they happen to generate throughout.
 * This allows for natural variation in the terrain of any individual biome, both in terms of shape and elevation.
 * For example, forests and deserts could form up on a hill without needing a special biome just for that purpose.
 * This additionally allows for smoother transitions between biomes.
 * Terrain is now smoother and more extreme.
 * Bedrock layers generate dependent on the world seed now.
 * New random number generator is used for overworld generation.

Gameplay

 * Advancements
 * "Light as a Rabbit" now has "Sweet Dreams" as its parent instead of "Adventure".
 * Reduced the number of biomes required to visit for the "Adventuring Time" advancement from 42 to 31, due to the removal of sub-biomes, with the following biomes now being required:
 * {| class="wikitable collapsed collapsible"

! Required biomes
 * }
 * }
 * }
 * }
 * }
 * }
 * }
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 * }
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General

 * Chunk format
 * Chunk’s &  have moved to a container structure in.
 * Chunk’s are now paletted and live in a similar container structure in.
 * Chunk’s is now  instead of.
 * Removed chunk’s  and moved everything it contained up.
 * has moved to.
 * has moved to.
 * and  have moved to.
 * and  have moved to.
 * has moved to.
 * has moved to.
 * has moved to.
 * has moved to.
 * has moved to.
 * Added  the minimum section y position in the chunk.
 * Added  containing data to support below zero generation.
 * Added  containing data to support blending new world generation with existing chunks.


 * Chunk render pipeline
 * Changed the prioritization order.


 * Clouds
 * Raised cloud level from 128 to 192.


 * Data packs
 * Data pack version number has been increased to 8.


 * Effects
 * Redesigned how effects look in the inventory screen.
 * Can display while recipe book is showing.
 * The list of effects are now shown to the right of the player's inventory, instead of the left side.
 * When the inventory effects list is visible, it will be hidden from the game view to reduce screen clutter.
 * There’s now two modes of seeing the effect list: compact and classic:
 * Classic is the pre-existing list of effects, one after another.
 * Compact is a single icon for each effect, suitable for small screen estate.
 * The game will automatically switch between the two looks to suit the available screen estate.


 * Height limit
 * Has been increased to 384 blocks, expanding 64 blocks up and 64 blocks down, with 320 being the limit upward and -64 being the limit downward.


 * Menu screen
 * Main menu background is changed to reflect Caves & Cliffs: Part II update.


 * Options
 * The Sneak and Sprint, and Auto-jump options have been moved to the Controls tab.
 * Render distance now causes chunks to load in a cylinder shape around the player instead of a square.
 * Changed default brightness to 50.


 * Performance
 * Now, various background tasks including world generation are executed on a background thread pool.
 * The size of the thread pool equals.
 * Maximum amount of threads is 255, instead of 7. This limit can be overridden by Java system property.


 * Player Spawning
 * Reworked world spawn selection algorithm.
 * Now spawns according to the same climate parameters that control biome placement and world generation: players should no longer be able to spawn in the ocean or some other inconvenient location.


 * Resource packs
 * Resource pack version number is now 8, as the following has been changed:
 * inventory.png now contains an extra sprite for a thin-layout version of the effect list in the inventory.


 * Scoreboards
 * Removed length limits for scoreboards, score holders and team names.


 * Server
 * now bundles individual libraries instead of merging all the files into single archive.
 * This change is meant to solve certain problems related to Java modules.
 * On startup, will unpack libraries into a directory configured by  (default: working directory).
 * To run different main class than server, use property.
 * Server classes are now signed.


 * Splashes
 * The splash "[this splash text has been delayed until part 2]" has been changed to "[this splash text is now available]".


 * Sprinting
 * No longer reduced to walking when touching the wall at low angles.


 * Tags
 * Renamed the block tag to.


 * Tick
 * Changed some internal details of block and fluid ticking to improve save times.


 * World types
 * Removed the Large Biomes and Amplified world types.

World generation

 * Blobs


 * Copper ore will generate in a different fashion - the blob generation was a temporary solution.


 * Strongholds


 * Try to generate fully encased in stone, or deepslate at low y-levels.

Unconfirmed features

 * Lush caves overview concept art.jpg Blossom


 * Can close.


 * Azalea Log


 * Between Java Edition snapshots 21w05a and 21w10a, many blocks (flowers, leaves, grass, ferns, sweet berry bushes, small dripleaves) had a block tag called "azalea_log_replaceable", possibly implying the existence of azalea logs.

Trivia

 * This is the first major update for that is split into two updates since Adventure Update in 2011.
 * This is also the first update that starts with experimental snapshots, instead of regular snapshots.