Java Edition 1.17

1.17, the first release of the Caves & Cliffs update, is an upcoming major update to set to release in mid-2021. It was first announced during Minecraft Live 2020 on October 3, 2020.

Blocks

 * Amethyst Bud
 * Grows from budding amethyst, which is found in amethyst geodes.
 * Starts out small, but grows into medium after a while, large after even more time and eventually becomes an amethyst cluster.
 * Unlike crops, each growth stage is a separate block instead of a block state.
 * Drops only when mined with a Silk Touch pickaxe.


 * Amethyst Cluster
 * The final, mature stage of the amethyst bud, which grows from budding amethyst in amethyst geodes.
 * Drops amethyst shards if broken, in an amount affected by Fortune, but can also be picked up with Silk Touch.
 * Emits a light level of 5.


 * Block of Amethyst
 * A block found in amethyst geodes.
 * Unlike the Budding Amethyst, the Block of Amethyst can be obtained when mined.
 * Can also be crafted with 4 amethyst shards.


 * Budding Amethyst
 * Generates amethyst crystals on any of its sides (if next to a water source block or air, and if the side is not against another block), in a given time.
 * Cannot be obtained when mined, even with Silk Touch, and does not drop anything.
 * Breaks immediately if pushed by a piston or sticky piston.
 * Cannot be pulled by sticky pistons.
 * Generates in amethyst geodes.


 * Calcite
 * An off-white stone that generates in geodes, between tuff and amethyst.


 * Candle
 * Crafted with honeycomb and string.
 * Comes with 16 dyed types and a yellowish non-dyed type.
 * Can be lit by any item that produces fire.
 * Up to 4 can be placed in a single block, similar to sea pickles, for a maximum light level of 12.
 * Only candles of the same color can be placed on the same block.
 * Only one can be placed on an uneaten cake and lit.
 * If any of the cake is consumed, the candle pops off.
 * Can be placed, but cannot be lit, underwater.


 * Copper Block
 * Can be crafted with 4 copper ingots, and can also be crafted back into 4 copper ingots.
 * Oxidises and changes texture to a turquoise-green over time.
 * Can be stopped from oxidizing by combining it with a honeycomb to create a Waxed Copper Block.
 * Can be crafted into cut copper.


 * Copper Ore
 * Generates randomly underground in small veins, but this has been confirmed to be a placeholder.
 * Has the same rarity as iron.
 * Generating starts at the same minimum level(s) as iron.
 * Can be smelted into a copper ingot.


 * Cut Copper
 * Can be made into stair and slab variants.
 * Oxidises and changes texture over time.
 * Can be stopped from oxidizing by combining it with a honeycomb to create Waxed Cut Copper.


 * Cut Copper Slab
 * Oxidises and changes texture over time.
 * Can be stopped from oxidizing by combining it with a honeycomb to create a Waxed Cut Copper Slab.


 * Cut Copper Stairs
 * Oxidises and changes texture over time.
 * Can be stopped from oxidizing by combining it with a honeycomb to create Waxed Cut Copper Stairs.


 * Dripstone Block
 * A decoration block.
 * Appears to be made of the same materials as stalactites and stalagmites but as a full cube.
 * Only generates in the Dripstone caves biome which is currently only available through single biome, caves, or floating islands world types.


 * Lightning Rod
 * Can be crafted with 3 copper ingots.
 * Nearby lightning strikes within a 32-block radius get redirected to the lightning rod.
 * Gives off a redstone signal with a strength of 15 if hit by lightning.
 * Can be activated directly by throwing a trident with Channeling at it during a thunderstorm, though this does not produce a redstone signal.


 * Pointed Dripstone
 * Can be either placed on a ceiling to create a stalactite, or on top of a block to create a stalagmite.
 * Can be combined to form longer stalactites and stalagmites.
 * Thrown tridents break pointed dripstone. Will also break when pushed directly or with a block by a piston.
 * Stalagmites break if not attached to something below, and hurt entities which fall on top of them.
 * Damage is relative to height: For example, jumping on a stalagmite deals of damage, and falling from 3 blocks deals  of damage.
 * Stalactites can fall or break if unsupported (unlike sand or gravel, they break apart on impact), and hurt entities they fall on.
 * Damage is relative to height: For example, one falling from 2 blocks deals of damage, and one falling from 3 blocks deal  of damage.
 * They drip water or lava into cauldrons if a source block is placed above the stalactite, and gradually fill the cauldron. Water drips even without any water above the block, but does not fill the cauldron.


 * Powder Snow
 * A variant of snow, Entities that walk over it will sink into it.
 * Leather boots can be worn to prevent entities from sinking into powder snow blocks.
 * Players can still crouch to descend with leather boots. Wearing leather boots also allows powder snow to be "climbed", like water or scaffolding.
 * When inside a powder snow block, a frosty vignette appears around the player's screen and any entity inside starts freezing and taking damage after a short time.
 * Wearing any piece of leather armor will stop the freeze effect.
 * Can be collected and placed with a bucket.


 * Sculk Sensor
 * A new redstone component that can be used for wireless redstone.
 * Does not generate naturally, only available from the Creative inventory.
 * Senses vibrations such as block placement, footsteps, and projectiles, and emits a redstone signal.
 * Particle of the Vibration.gif Emits particles when it senses a vibration nearby.
 * Will emit a different strength if connected to a comparator, and the signal strength is based on the vibration's frequency.
 * Does not detect not ambient weather such as rain.
 * Wool can occlude its ability to sense. This can be placed between or completely around the source of the input.


 * Tinted Glass
 * A black variant of glass that does not let light pass through.
 * Can be crafted with 4 amethyst shards and a glass block.
 * Stained glass cannot be used to craft tinted glass.
 * Drops itself if mined without Silk Touch or even by hand, unlike glass.


 * Tuff
 * A grayish stone that composes the outer layer of amethyst geodes.
 * Texture may be subject to change.

Items

 * Amethyst Shard
 * Obtained from breaking amethyst clusters.
 * The amount dropped can be increased with the Fortune enchantment.
 * Can be used to craft tinted glass, blocks of amethyst and a spyglass.


 * Bucket of Axolotl
 * Obtained by using a water bucket on an axolotl, similar to fish.
 * Can be used to carry around and empty axolotls.


 * Bundle
 * Crafted with 2 string and 6 rabbit hide.
 * Used to store other items (except shulker boxes) inside of it.
 * Can only hold a stack of items, but is able to hold different types of items inside of it.
 * Items with smaller stacks, such as ender pearls, take up more room in a bundle, and non-stackable items take up the whole bundle.
 * The bundle's contents can be opened by pressing while holding it, throwing out its entire content into the world.
 * Right-clicking a bundle in the inventory empties one item from the bundle.
 * Even though bundles are not stackable, bundles can be nested.
 * Can hold up to 16 bundles.
 * Only empty bundles can be placed in other bundles without using commands.
 * Has a GUI when hovering over it.
 * Shows contained items in its GUI's inventory slots when hovering over it, as well as fullness as a number.
 * Note: Bundles can hold any amount of any item if added using commands.


 * Copper Ingot
 * Obtained by smelting copper ore.
 * Used to craft copper blocks, lightning rods and spyglasses.


 * Powder Snow Bucket
 * Obtained by using a bucket on powder snow.
 * Can be used to place a powder snow block wherever it is used, or can be used to fill cauldrons with powder snow.


 * Spawn eggs
 * Added axolotl spawn eggs.


 * Spyglass
 * Crafted with 2 copper ingots and an amethyst shard.
 * When used, it zooms in on wherever the player is looking, but limits their view to a square.
 * The scope texture is a glass square with a copper border.
 * The overlay that limits the view can be removed with a resource pack or by pressing.
 * There is a unique animation for using the spyglass, which is visible in third person perspective.

Mobs

 * Based on the Mexican salamander with the same name in real life.
 * Doesn't spawn naturally yet, must be spawned in with a spawn egg.
 * The first amphibian added to Minecraft.
 * Can be caught in a bucket like fish.
 * Can be bred using tropical fish or buckets of tropical fish.
 * Come in different colors (leucistic, yellow, brown, white, and purple/pink, and a rare blue Axolotl).
 * Plays dead when damaged, receiving Regeneration. Appears to turn invisible or teleport after this, although the latter may be just a bug or a glitch.
 * This regeneration ability is likely based on how real axolotls can regrow lost limbs.
 * Attacks drowned, guardians, elder guardians and fish, damage not yet official.
 * Attacks drowned, guardians, elder guardians and fish, damage not yet official.

World generation

 * Amethyst Geodes
 * A new feature found uncommonly underground (can rarely appear exposed to the surface close to sea level).
 * Contains blocks of amethyst and budding amethyst blocks, which are encased in a shell of calcite and tuff.
 * Also generates with a small air pocket nearby which may open into the geode.
 * Generally generates at or below sea level (y = 63).
 * Most commonly generates at lower levels (y = 0 to y = 40)
 * Overrides standard caves and ravines, but is overridden by abandoned mineshafts.
 * Currently has a high generation rate, presumably for testing purposes which was also done with ruined portals before.


 * Dripstone Caves
 * A new underground biome, consisting of a massive cave biome containing vast quantities of stalactites and stalagmites.
 * Made up of primarily dripstone blocks and stone, with large clusters of dripstone blocks hanging from the ceiling, pointed dripstone on the floor and ceiling and many pools of water.
 * Does not generate naturally in normal worlds, and can only be generated using buffet worlds with "Dripstone Caves" selected as the source biome.

Command format

 * Modifies the inventory of a block or entity.
 * This command has three forms:
 * – same as old
 * – modifies item (without copying).
 * {{cd|/item copy
 * Whether entities take damage from freezing inside of powder snow.
 * Whether entities take damage from freezing inside of powder snow.

Gameplay

 * Death messages
 * Added 4 new death messages, related to freezing in powder snow and being skewered by a falling stalactite:
 * " froze to death".
 * " was frozen to death by ".
 * " was skewered by a falling stalactite"
 * " was skewered by a falling stalactite whilst fighting "


 * Loot tables
 * Rolls, set_damage, and possibly other parameters now require "type:uniform" (or other valid values for "type") when using min-max for numbers. set_count has had the same requirement for a few versions.
 * New condition:
 * Checks range of value.
 * Parameters:
 * – see "New value providers" section (currently combination of random generators and score)
 * – min/max range
 * New functions:
 * Modifies enchantments on item.
 * Parameters:
 * – map of enchantment id to level value (can be score or random number)
 * – if, change will be relative to current level. If , level will be replaced with current value (default behavior)
 * Sets tags needed for banner patterns. Parameters:
 * - list of pattern objects:
 * - name of pattern (square_bottom_left, bricks, etc.)
 * - name of color (light_gray, etc.)
 * - if true, new elements will be appended to existing ones instead of replacing
 * New value providers:
 * Returns scaled scoreboard value.
 * Parameters:
 * – scoreboard name
 * – same as in  predicate
 * – scaling factor (float)
 * – same as in  predicate
 * – scaling factor (float)

General

 * Particles
 * Added 3 new particle types:, , and.


 * Tags
 * Added the block tag.
 * Contains all 17 types of candle cake.
 * If the player puts a candle on a cake, and keeps clicking the candle on the cake, the candle will be duplicated.
 * Blocks in this tag are considered candle cakes and can be lit, if they have the block states set to false.
 * Added the block and item tags.
 * Contains all 17 types of candles.
 * Blocks in this tag are considered candles and can be lit, if they have the block states and both are false.
 * Cakes use this tag to determine if a candle item can be placed on it or not.
 * Added the block tag.
 * Contains cauldrons, water cauldrons, lava cauldrons and powder snow cauldrons.
 * This tag is used in certain pathfinding processes.
 * Added the block tag.
 * Contains amethyst blocks and budding amethyst.
 * Blocks in this tag play play the "amethyst block chime" sound repeatedly for a short amount of time after being stepped on, gradually decreasing in volume.
 * Added the block tag.
 * Contains the block tag and dirt.
 * Used in dripstone generation to determine what dripstone can replace and what pointed dripstone can generate on.
 * Added the item tag.
 * Contains leather boots, leather pants, leather tunic, and leather cap.
 * Having an item in this tag in an armor slot prevents players from freezing.
 * Added new tag type.
 * Added the item tag.
 * Contains leather.
 * Baby piglins do not attempt to pick up items in this tag. Adult piglins are unaffected. Baby piglins still follow the other rules adult piglins follow.
 * If an item is in this tag while simultaneously being recognized as a wanted item by piglins, this tag takes precedence.
 * Added the game event tag.
 * Contains the step, falling, and shooting projectile events.
 * Game events in this tag will be ignored by sculk sensors if the source entity is sneaking.
 * Added the block tag.
 * Contains snow and powder snow.
 * Blocks in this tag will create snow stepping noises while the player walks in them.
 * Added the block tag.
 * Contains the block tag.
 * Blocks in this tag will prevent sculk sensors from hearing vibrations if the block is between the sculk sensor and the vibration.
 * Added the item tag.
 * Contains raw and cooked porkchop.
 * Piglins can eat items in this tag.
 * Eating refers to the piglin seeking out and picking up an item without appearing in its inventory, thus vanishing.
 * Added the entity tag.
 * Contains rabbits, endermites, and silverfish.
 * Entities in this tag can walk on top of powder snow.
 * Added the game event tag.
 * Contains every game event.
 * Game events in this tag will trigger sculk sensors.

Blocks

 * Cakes
 * Have a variation called "Candle Cake".
 * Can be created by using a candle on an uneaten cake.
 * The candle on the cake comes with 17 colors, depending on the color of the candle used to create it.
 * Pop out the original candle when any of the cake is eaten.


 * Banners
 * The unused "base" pattern has been renamed to the "field" pattern and given proper translation strings (its ID is still "base").


 * Cauldrons
 * Can now be filled with lava and powder snow.
 * Lava filled cauldrons can damage players and mobs inside of it, and give off a redstone comparator signal of strength 1.
 * Powder snow cauldrons are formed when cauldrons are under the sky during snowfall.
 * Can also be filled with powder snow by a powder snow bucket on it.
 * Have been split into normal, water, lava, and powdered snow cauldrons.


 * Dispenser
 * Can now place powder snow using a powder snow bucket.
 * Also can remove it using a bucket.


 * Grass Path
 * Renamed to "Dirt Path", as per Bedrock Edition.
 * The block ID has also been changed to.
 * Can now be made with dirt, coarse dirt, mycelium, and podzol.


 * Lapis lazuli block
 * Renamed to "Block of Lapis Lazuli".


 * Pistons
 * Particles now appear if a block is broken by a piston.
 * Sounds, however, do not.
 * Breaks Budding Amethyst if pushed/pulled w/ a piston/sticky piston.


 * Rails
 * Are now able to be waterlogged.
 * No longer break when contacted by water.


 * Shulker boxes
 * Now mimics the opening and closing of a shulker.
 * Unlike its mob counterpart, it does not elevate the player when they are standing on it.


 * Structure block
 * Default mode of structure blocks is now "Load". "Data" is now hidden by default.
 * "Data" can be accessed by clicking the mode button while holding the key.


 * Water
 * Flowing water no longer breaks rails.

Items

 * Clock
 * The texture has been changed. The gold is now more vibrant and better matches other instances of gold in the Texture Update texture.


 * Compass and Lodestone Compass
 * The texture has been changed. The iron is now more vibrant and better matches other instances of iron in the Texture Update texture.


 * Firework Rockets
 * Simple firework rockets with one gunpowder can now be crafted using the recipe book.


 * Pufferfish
 * The strength of the poison effect has been decreased from IV to II.

Mobs

 * Shulkers
 * If a shulker is hit by another shulker's projectile, it now has a chance of spawning a new shulker. Shulkers are more likely to spawn new shulkers when there are fewer shulkers nearby.

Non-mob entities

 * Experience Orbs
 * Will now sometimes merge when in large quantities, to improve performance.
 * Merging will not affect the amount of experience gathered from collecting the merged orbs.
 * No longer follow dead players.


 * Minecarts
 * Can now move in water, but move considerably slower than they do on land.

World generation

 * Biomes
 * Biome-specific sky colors now blend more smoothly.

Command format

 * Removed command.
 * Replaced with.
 * Replaced with.

Gameplay

 * Absorption effect
 * The yellow absorption hearts will now stay yellow if the player has the Poison or Wither effects, instead of appearing empty.


 * Loot tables
 * Loot tables can now access scoreboard values by UUID.
 * Loot table values inside random number generators can now be nested.
 * Changed condition:
 * parameter has now been replaced with . It can either contain value from old field (like ) or be an score holder name in form.
 * Changed function:
 * This function now has parameter. If, change will be relative to current damage. If , damage will be replaced with current value (default behavior)
 * Changed function:
 * This function now has parameter. If, change will be relative to current item count. If , item count will be replaced with current value (default behavior)
 * Changed function:
 * parameter can now be set to, to access command storage.


 * Recipe Book
 * Some recipe-unlocking advancements had criteria names changed.
 * The chiseled nether bricks recipe is now unlocked by having a nether brick slab instead of a nether bricks block.


 * Snowfall
 * During snowfall, cauldrons under the sky now slowly fills with powder snow.

General

 * Custom dimensions
 * Added height and min_y variables to dimension types, allowing for the height limit to be increased in custom worlds settings.


 * Data and Resource Packs
 * Changed the  number in   from 6 to 7.
 * Changed the resource pack version number from 6 to 7, as the following have been changed:
 * Drowned texture mirroring has changed.
 * Slots for the game mode selector are now 26 pixels instead of 25.
 * Data pack version is also changed to 7.


 * Dedicated servers
 * A dedicated server can enforce custom resource packs by setting in . When this option is used, players will be prompted for a response and will be disconnected if they decline the required pack.


 * Entity storage
 * Entities have been extracted from main (terrain) chunks and are now stored in separate directory (similar to POI storage). Those new files are still region files with NBT.


 * Libraries
 * The game now uses javabridge 1.1.23 instead of 1.0.22.


 * Menu screen
 * Buttons tied to a set of values can now be scrolled through.
 * Clicking on a menu button changes it to the previous value.
 * The debug mode can now only be accessed by holding instead of  while clicking on the world type button.


 * Servers
 * Removed the server setting.


 * Translation strings
 * The "World Type" string no longer contains a colon (":"). The colon is still visible in-game, however.
 * Changed "Use VSync" to "VSync".
 * Removed the unused string for enabling VBOs, "Use VBOs".
 * Added strings, "Mode", "Type", "Triggering", and "Track output". These are read out by the narrator for buttons in the command block UI.

Blocks

 * Restoring clay pots.png


 * Seems to use the texture of clay block.
 * Ceramic Shards can be incorporated into an unfired pot.
 * Can be fired by lighting fire under the pot.
 * Pot can fit up to 8 Ceramic Shards.


 * painted clay pot.png


 * Seems to use the texture of terracotta.
 * Created by firing a clay pot.
 * Upon firing, any placed Ceramic Shards become permanently incorporated on to the clay pot.


 * Azalea Leaves.png Blooming Azalea Leaves.png


 * Part of a new tree, marking the location of the lush cave.
 * Has variants with either no blossoms, pink blossoms, or purple blossoms.


 * Baby azalea tree.png Baby blooming azalea tree.png Azalea Sapling


 * Has variants with either no blossoms, pink blossoms, or purple blossoms


 * Azalea Roots.png


 * Part of the Azalea tree.
 * Resembles a dirt block, but with the roots of the Azalea tree intertwined.
 * Probably is the source of all the life in lush caves.
 * May be a new variant of the dirt block.


 * Roots bloody roots.png


 * Seen in the distance of a lush caves biome behind a spore blossom.
 * Can also be seen hanging beneath the dirt variant that spawns below the Azalea tree and on the ceiling in the axolotl clip, possibly just a decorative feature of this block.


 * New Vine.png New Vine 2.png


 * Light source.
 * Grows edible glow berries.


 * Spore Blossom.png


 * Can be placed on ceilings.
 * Sends particles downward when opened.
 * This item can be found in the lush caves.


 * Dripleaf Plant.png


 * A plant that can be used for platforming.
 * If the player stands on top of the plant for 2 seconds (40 ticks), the player falls through the plant.
 * Can be placed on a grass block.


 * Baby dripleaf plants.png Small Dripleaf Plant


 * Appear highly varied in models.


 * Unidentified foliage object.png Moss Block


 * An opaque block that appears grassy on all sides.
 * Can be found in lush caves.


 * Foliage carpet.png Moss Carpet


 * Same texture as the moss block, but one pixel thick.


 * Sculk Block.png


 * Generates in the mysterious new cave biome, referred to as the "deep dark" temporarily.
 * Has an animated texture.


 * Unidentified Sculk Block.png


 * Generates in the deep dark biome
 * Has a different top texture than the Sculk Block and Sculk Chute.


 * Sculk Something.png


 * Generates in the deep dark caves.
 * While this block's use and function is currently unknown, it is speculated that this block is the source of the other sculk blocks due to the block always appearing in the middle of each sculk growth. This could possibly mean that the other sculk blocks grow out from the sculk chute, however this is just speculation.
 * Has the same texture as the skulk block, even though part of the skulk chute is made of bones.


 * Sculk Growth.png


 * Generates in the deep dark cave biome.
 * Generates in a layer on top of blocks, similar to snow.
 * Some have parts that are transparent, allowing the player to see the block it is on top of.


 * Unnamed Stone.png Darkstone/Deepstone


 * Can be found around the dark deep cave biome walls.
 * Can be found in large groups.


 * Unspecified underground light sources


 * A video by Henrik Kniberg explicitly states that the temporary showcased feature of ore blocks emitting light was intended as a placeholder for underground light sources, potentially hinting at further new cave light sources.

Items

 * Goat Horn.png Goat Horn


 * This feature is currently available in beta development versions of Bedrock Edition 1.16.200.
 * Goats have a chance to drop this item when they ram into a block.
 * Holding while holding this item plays the raid horn sound effect.


 * Brush.png


 * Used to sweep away debris from archaeological items.
 * Sweeps debris off archaeological items one layer at a time. If interrupted, the block it was being used on simply disappears, and does not yield custom block heights.
 * Also comes in a blue-green variant: Brush 2.png
 * This may imply a connection to copper, as both the variant and normal brushes have corresponding colors to the blocks shown.


 * Blue Ceramic Shard.png Orange Ceramic Shard.png Ceramic Shard 1.png Ceramic Shard 2.png Ceramic Shard 3.png Ceramic Shard 4.png


 * Obtained with a brush at archeological sites.
 * Come in different colors and different designs, each depicting a different picture, such as an ender dragon, a cow, Alex, a skeleton, a tree and a vindicator.
 * Can be placed/customized on clay pots.
 * Currently using placeholder art, according to Jasper Boerstra.




 * Can be eaten.
 * Used as a light source.




 * Spawn eggs for the new mobs are added.
 * Warden Spawn Egg.png The Warden spawn egg is visually confirmed but not yet implemented.
 * Goat Spawn Egg BE1.png The Goat spawn egg is present in the Bedrock Edition beta.

Mobs

 * Glow Squid.png


 * Originates from Minecraft Earth.
 * Glows in the same way that magma cube cores, vexes, blazes and the eyes of spiders, drowned, and endermen do.
 * Spawns in deep ocean biome.
 * Likely to spawn in flooded caves as well.
 * Was decided on based on a mob vote between it, the Moobloom from Minecraft Earth, and the Iceologer from the Minecraft Dungeons DLC Creeping Winter. Failing mobs are less likely to be added but still have a chance to be implemented in the future.


 * Goat.png Goat


 * This feature is currently available in beta development versions of Bedrock Edition 1.16.200.
 * Spawns in mountain biomes.
 * Can jump high to avoid obstacles, about 5 blocks tall.
 * Attacks nearby animals by charging and knocking them a considerable distance.
 * Takes reduced fall damage.
 * Avoids Powder Snow by jumping over it.
 * Can be bred with wheat, and produces 3-8 babies at once.
 * Has a chance to drop a goat horn when ramming into a block.


 * Warden.png




 * Spawns in the new deep dark biome.
 * It is the first blind mob.
 * When sensing movement, it moves toward the source of the movement.
 * When attacked, it path finds toward the player.
 * Seems to follow the same rules as the sculk sensor when detecting noise.
 * When it detects a vibration, the growths on its head rattle and light up, similar to the sculk sensor.
 * If any projectile, like a snowball or an arrow, lands near the Warden, it causes the mob to head to the location of where the projectile landed, due to the projectile itself creating movement and noise, therefore distracting the warden.
 * Does not detect players that are sneaking.
 * Can detect players that are invisible.
 * Can detect players using elytra.
 * When aggravated for long enough, the warden follows the player continuously, regardless of any other distractions.
 * Attacks any mob that makes vibrations, not just players.
 * Can detect ringing bells.
 * Can detect players eating.
 * Incredibly strong, doing damage, bringing players wearing full netherite armor from full health to  health points.
 * Has at least health points, although it is estimated to have up to, putting it on par with the iron golem and ravager.
 * A mob designed to be extremely difficult, and fled from.
 * Has a way to counter the strategy of building up 3 blocks to avoid attacks.
 * At least as fast as the player's walking speed.
 * Seems to use the energy of vibrations to move faster.
 * Seems to have knockback resistance.
 * The warden's chest has a glowing core that appears to brighten and dim in tandem with the ambient lighting of the deep dark cave biome.
 * The core creates a low throbbing sound as it pulses. The sound and animation seem to speed up rapidly when the warden notices a player.
 * Is about 3.2 blocks tall, making it one of the tallest mobs in the game, exceeding the iron golem and enderman in height and width (the same).

World generation

 * Archaeological excavation


 * A new semi-underground structure where archeological items and ceramic shards can be found.


 * biome


 * New biome at the "deepest depths of the world".
 * Wardens can spawn here.
 * May contain candles.
 * Contains sculk blocks, and the new Skulk Sensor Blocks, a new block that responds to vibrations.
 * Contains a new Unnamed Block.




 * Generate below azalea trees.
 * Contains tall grass, glow berries, dripleaf plants, spore blossoms, moss blocks, moss blankets, clay blocks, azalea roots, and azalea saplings.
 * Can spawn axolotls.




 * Seems to be possibly a large tunnel-like cave.
 * Not much is known about this biome yet, but it was confirmed on Twitter by Henrik Kniberg.
 * It's a variation of caves rather than a biome, as stated by Henrik Kniberg.


 * Possibly contain "catacomb" style branching cave sections.




 * More extreme and smooth terrain.
 * Likely change to the generation of alternate stone types, to make them appear in larger but less numerous deposits.
 * Possibly seen in a screenshot tweeted by Henrik Kniberg, in which Diorite appears to generate in a long and flat horizontal strip, rather than a small unevenly shaped patch.

Gameplay



 * The player can find items and blocks in gravel and dirt inside the dig site structure by using the brush.
 * Possible items shown in the preview footage include:
 * Ceramic shards of varying color that depict different images.
 * Diamond blocks and Emerald blocks are probably not a part of this list and serve as a placeholder.




 * While in the deep dark cave biome, the ambient lighting occasionally dims temporarily, limiting the player's visibility. This serves as a warning that the warden is nearby.




 * An action can cause vibrations in the air, which can be picked up by sculk sensors and wardens
 * Can be caused by walking (but bats?), block placing, block breaking, doors or trapdoors opening, chests of any kind opening, pistons activating, and projectiles such as snowballs, eggs, or arrows landing. This does not include ambient weather such as rain or snow.

World generation

 * Caves


 * Complete generation overhaul.
 * Many variations on cave types and cave design.
 * Biomes within caves introduced.




 * A new underground water level generation aspect has been introduced, which allows for certain areas of a world to generate with a specified water level different from that of another area (such as sea level).
 * Caves & Cliffs Mountains largersize.png.]]Allows for the generation of larger underground lakes and connections to oceans.
 * Allows for the generation of many underground waterfalls.
 * Allows for underwater entrances.




 * Height dependent generation.
 * Revamped, featuring some new small spruce trees on the slopes and ice or packed ice above the peaks.
 * Contain snow blocks, goats, and a new form of snow called powder snow, which is said to be "snowier than snow".


 * Ore veins


 * To be revamped, possibly to balance the generation of copper.
 * Some stone appears a little different and when that stone is mined, more of the ore should be found behind it.


 * Other Stones


 * Granite, Diorite, and Andesite spawn in layers of rock in straight lines instead of splotches.  Example-of-other-stone-generation.png

Blocks

 * Wool


 * Used to block a sculk sensor's ability to sense vibrations.

Structures

 * Underground Cabin
 * Seen in the Deep Dark biome during the Minecraft Live 2020 stream.
 * Consists of a chamber with a cobblestone floor and stripped log support beams, containing 3 barrels, a blast furnace, and a large chest, with cobwebs and candles in and around it.
 * May possibly not be a generated structure, but instead a construction built for the purpose of the Warden showcase.

General

 * Height limit
 * May be increased.
 * As of 20w49a. World-height related values are now exposed for customized worlds, which might confirm that height limit might get removed or increased.

Trivia

 * This is the first Java Edition update to add a new ore to the overworld since emerald ore was added in  in 2012.
 * Similarly, this is also the first Java Edition update to add a real-world metal into the game since Classic 0.0.14a in 2009, which brought both iron and gold.
 * As of 20w45a, Waxed Lightly Weathered Cut Copper Stairs is the longest item name in the game, with 41 characters.