Caves & Cliffs

Caves & Cliffs is the name of one released and one upcoming major themed update set to release for. The first part was released as Java Edition 1.17 and Bedrock Edition 1.17.0 on June 8, 2021, which added geodes, copper, new blocks and mobs. The second part will be released as Java Edition 1.18 and Bedrock Edition 1.18.0 at the end of 2021 and will include expanded caves, increased height and depth limit, new mountain generation, and new biomes. It was announced in Minecraft Live 2020, and on April 14, 2021, Mojang Studios announced that the update would be split into two updates due to the amount and complexity of content, as well as team health.

On, Part I started development with snapshot 20w45a, which was released on November 4, 2020. The first pre-release for Caves & Cliffs: Part I was released on May 27, 2021, and the first release candidate on June 4, 2021. As for Part II, development continued with 1.18 Experimental Snapshot 1, which was released on July 13, 2021.

On, Part I started development with beta 1.16.200.52, which was released on October 28, 2020. Most of the Part I features were behind experimental gameplay toggle until the Part I release and were not included in the full 1.16.200, 1.16.210, and 1.16.220 release. As for Part II, development continued with beta 1.17.30.23, which was released on August 25, 2021. In 1.17.10, released on July 13, 2021, non-beta users were able to test out most of early Part II features behind experimental gameplay.

Both Java and Bedrock editions received Caves & Cliffs: Part I on June 8, 2021.

Additionally, features from this update will be also released for soon in 1.17 in 2021.

Blocks

 * Amethyst Buds and Amethyst Cluster
 * Grow on any side of budding amethyst blocks over time.
 * Breaking a fully developed amethyst cluster with a non-Silk Touch pickaxe drops 4 amethyst shards.
 * These can be crafted into spyglasses and tinted glass.


 * Azalea
 * Has variants of bushes and trees with either no blossoms or pink blossoms called flowering azalea.
 * Can be found in the biome.
 * Can be obtained from azalea leaves.


 * Azalea Leaves
 * Part of a new tree (azalea tree), marking the location of a lush cave.
 * Has variants with either no blossoms or pink blossoms called flowering azalea leaves.
 * Drop azaleas when broken, similarly to other leaf blocks dropping saplings.


 * Big Dripleaf.png Big Dripleaf
 * A plant that can be used for platforming.
 * If a player or mob stands on top of the plant for two seconds (40 ticks), the plant tilts and the player or mob falls through the plant.
 * Can be placed on any solid block and water.
 * Can have bone meal applied to grow taller.
 * Can be used for new projects and obstacle courses.


 * Block of Amethyst.png Block of Amethyst
 * Can be crafted with four amethyst shards.
 * Naturally generates in amethyst geode structures.
 * Makes a sparkling sound when placed or walked on.
 * Can be mined in amethyst geode by an iron pickaxe or better.


 * Budding Amethyst.png Budding Amethyst
 * When it receives a random tick, it has a 20% chance to generate or grow an amethyst bud on one of its sides.
 * Relatively rare, generates only in amethyst geode structures.
 * Only obtainable in Creative Mode.


 * Calcite.png Calcite
 * Spawns between smooth basalt and blocks of amethyst, much like real-life geodes.
 * Can also generate in stony peaks.


 * Candles and cakes with candles
 * A light source with a light level of 3.
 * Up to four can be placed in a single block, similar to sea pickles. If 1 more candle is placed in a block, it increases the light level by 3, making a max light level of 12.
 * Can be lit with a flint and steel, fire charge, an arrow fired from a flame-enchanted bow, or a fire charge shot by a dispenser if it hits the candle.
 * Have variants for uncolored and all 16 colors.
 * Uncolored candle is crafted with 1 string and 1 honeycomb.
 * Colored candle is crafted using one of the 16 dyes and one uncolored candle.
 * Right-clicking a candle on an uneaten cake makes a "birthday cake", which can have a single candle placed on it.
 * Example: Cake with Candle.png
 * If the cake is eaten, the candle pops off.


 * Cauldron.png Cauldron
 * Can be filled with lava $$, which was previously a exclusive.
 * Can be filled from the snowfall in mountains creating powder snow, which can be collected using buckets.


 * Cave Vines
 * Grow on the bottom side of a block.
 * Grow in.
 * Can be planted using glow berries.
 * Produce edible glow berries, which are a light source.
 * Using bone meal on a cave vine produces glow berries (similar to sweet berry bushes) instead of growing the vine itself, unlike other vines.
 * Can be extended downward using glow berries, and has an age mechanic, similar to kelp, such that every time it ages it has a chance to grow Glow Berries.


 * Cobbled Deepslate.png Cobbled Deepslate
 * Takes slightly longer to mine than normal cobblestone.
 * Mining deepslate without Silk Touch drops cobbled deepslate, similar to stone dropping cobblestone.
 * Can be crafted or cut into several variants (see Cobbled Deepslate for more information).


 * Copper Block and variants
 * Copper blocks are used for crafting and storage.
 * Made with nine copper ingots.
 * The stonecutter can be used to craft the different copper block variants.
 * Only cut copper can be used to make stairs and slabs.
 * Example:
 * Made with four copper blocks.
 * Cannot be turned back into regular copper blocks or copper ingots.
 * Develops a patina of pale green copper carbonate over multiple stages, exposed, weathered, and oxidized.
 * Honeycombs can be used to make waxed copper, which does not progress beyond the patina stage it has at the time. The wax can be scraped off with an axe, but it does not drop the honeycomb.
 * Axes can be used to undo the oxidisation stages one at a time.


 * Copper Ore.png Copper Ore
 * New ore that is found underground.
 * Drops Raw Copper when broken, like other metal ores.
 * Spawns in ore veins similar to iron (current generation is not the final version).
 * Can be smelted into a copper ingot, which can be used to craft copper blocks, lightning rods, and spyglasses.
 * Does not generate below Y = 0.


 * Deepslate.png Deepslate
 * Can be found below Y = 0.
 * Generates as base stone below Y = 0, gradually replacing stone.
 * Takes twice as long to mine than normal stone.
 * Drops cobbled deepslate when mined without the Silk Touch enchantment.


 * Deepslate Ores
 * New overworld ore variants that generate in the deepslate layer (below Y = 0).
 * Functionally similar to their normal ore variants but take twice as long to mine.
 * Ores that generate with deepslate variants include iron, gold, lapis lazuli, diamond, and redstone.
 * Ores that do not generate below Y = 0 still have deepslate variants, however these variants do not generate naturally.


 * Dripstone Block.png Dripstone Block
 * Spawn in.
 * Can be used to grow Pointed Dripstone.
 * Can be crafted from four pointed dripstone.


 * Glow Lichen (texture) JE1.png Glow Lichen
 * A decorative block.
 * Can be waterlogged.
 * Looks similar to vines.
 * Emits a light level of 7.
 * Spreads to a random nearby block in a cross formation when bone meal is applied.
 * Generates in caves.
 * This block was hinted at by Henrik Kniberg, who explained that the glowing ores at Minecraft Live 2020 were prototypes for this.


 * Hanging Roots JE2 BE1.png Hanging Roots
 * Decorative block.
 * Part of the new azalea trees.
 * They can be grown by applying bone meal to the rooted dirt, the root will grow at the bottom of the block.
 * Can also be obtained by using a hoe in the rooted dirt.


 * Lightning Rod.png Lightning Rod
 * Crafted with 3 copper ingots.
 * Redirects nearby lightning strikes to the top of the rod, which can prevent flammable structures from catching fire during thunderstorms.
 * Emits a redstone signal when struck by lightning, with the exception of when it gets struck by lightning from a channeling trident in a thunderstorm, in which it emits nothing.
 * Can be oriented in different directions depending on the players orientation.


 * Block of Raw Iron, Block of Raw Gold, and Block of Raw Copper
 * Crafted from 9 raw iron, raw gold or raw copper.


 * Moss Block.png Moss Block
 * An opaque block that appears grassy on all sides.
 * Using bone meal can cause it to grow grass, tall grass, moss carpet s and both types of azalea bushes on it and in its vicinity.
 * Bone meal can also cause it to grow over (expand) and convert stone surfaces, sand, dirt, etc. but not grass surfaces.
 * Breaks when pushed by a piston.


 * Moss Carpet.png Moss Carpet
 * Same texture as the moss block, but one pixel thick like carpet.
 * Can occupy the same block with grass.


 * Pointed Dripstone.png Pointed Dripstone
 * Come in two forms, stalactites and stalagmites.
 * Stalactites hang from the ceiling and drip water or lava, based on what is above them. The stalactites drip water naturally without a source block above it, but these drips do not fill a cauldron.
 * Placing a cauldron under a stalactite slowly fills the cauldron with water or lava depending on the source block above them (enables renewable lava).
 * If the block on which a stalactite hangs is broken, the stalactite falls, causing damage to players and mobs directly underneath. They do not take any damage if they are airborne.
 * Stalagmites are found on the floor of the cave and deal damage if landed on.
 * The damage inflicted of pointed dripstone is directly proportional to the height from which the stalactite or player/mob falls from.


 * Powder Snow.png Powder Snow
 * Similar to snow, but entities fall through it. The fall is similar to the effect of cobwebs, but faster.
 * If the player does not have any leather armor equipped and they walk or fall in, they start to freeze and take damage.
 * Freezing lowers the player's FOV (field of view), turns the health bar blue, and puts a frosty vignette on their screen.
 * Any leather armor prevents freezing.
 * Wearing leather boots allows the player to walk on top of powder snow and make it function like scaffolding.
 * Most mobs can also take freezing damage. Polar bears, strays, and snow golems are immune to freezing.
 * Certain mobs have unique properties with powder snow.
 * Skeletons convert into strays after staying inside of powder snow for too long.
 * Goats avoid and jump across powder snow.
 * Foxes, rabbits, endermites, and silverfish can walk on top of powder snow.
 * Shulkers and vexes are unaffected by powder snow.
 * "Snowier snow" was announced to be part of the Mountains biome in the biome vote at MINECON Live 2019, a joke teaser for powder snow.
 * Cauldrons slowly fill up with powder snow when they are placed in a snowing.biome


 * Rooted Dirt.png Rooted Dirt
 * Part of the Azalea plant.
 * Resembles a dirt block, but with the roots of the Azalea tree intertwined.
 * The first roots that exist in Minecraft.
 * Planned to lead to the Lush Caves biome.
 * When bonemealed, hanging roots grow on the bottom block.


 * Sculk Sensor.png Sculk Sensor
 * Generates in the deep dark cave biome.
 * Can be used for wireless redstone.
 * Senses vibrations created by anything (excluding ambient weather). See Sculk Sensor for more information.
 * Wool can occlude its ability to sense in a certain direction. This can be placed between or completely around the source of the input.
 * Cannot detect players sneaking.
 * Emits particles ( Vibration JE1 BE1.gif ) when it senses a vibration nearby, except when waterlogged.
 * Are not affected by ambient weather such as rain, nor other sculk sensors and/or the warden.


 * Small Dripleaf.png Small Dripleaf
 * Appears highly varied in models.
 * Can be placed only in water or on clay, which counts as a 'moist' block.
 * Bone meal can be applied to turn it into Big Dripleaf.
 * Can be sold by the Wandering Trader.


 * Smooth Basalt.png Smooth Basalt
 * Spawns as an outer covering of amethyst geodes on the outer side of calcite, similar to real-life geodes.
 * Very similar in texture to calcite but different in color.
 * Can be obtained by smelting basalt in a furnace.


 * Spore Blossom
 * Can be placed on ceilings.
 * Sends particles downward when opened.
 * Creates ambient particle effects, similar to the nether biomes, but non-biome dependent, however, its natural generation is dependent of the Lush Caves, meaning that Spore Blossoms currently don't generate naturally in default worlds.


 * Tinted Glass.png Tinted Glass
 * A type of glass that does not allow light to pass through.
 * Crafted with a glass block in the middle and 4 amethyst shards in a cross shape.
 * Drops itself when broken, even without Silk Touch, unlike glass.


 * Tuff.png Tuff
 * Decorative block.
 * Generates below y = 0 in the form of patches.

Items

 * Amethyst Shard.png Amethyst Shard
 * Drops from amethyst clusters.
 * Used to make spyglasses and tinted glass.


 * Bucket of Axolotl.png Bucket of Axolotl
 * Obtained by using a water bucket on an axolotl, similar to fish.

be
 * Bundle.png Bundle
 * Can contain one cumulative stack of any variety of item types.
 * Stack sizes are sustained. For example, a bundle containing 32 blocks with a stack size of 64 could hold only an additional 8 ender pearls, as the stack size of an ender pearl is 16; the half stack of ender pearls added to the half stack of blocks is calculated as one full stack. Un-stackable items like minecarts remain un-stackable.
 * Displays a blue bar, similar to a durability bar, that shows how full it is.
 * Items drop to inventory when right clicked.
 * Are crafted with rabbit hide and string.


 * Copper Ingot.png Copper Ingot
 * Created by smelting raw copper.
 * Can be used to craft copper blocks, lightning rods, and spyglasses.


 * Glow Berries.png Glow Berries
 * Grow from cave vines.
 * Can be eaten.
 * Used as a light source.
 * Loved by foxes as much as sweet berries.
 * Foxes can pick and eat glow berries from the vine similar to sweet berry bushes.


 * Glow Ink Sac.png Glow Ink Sac
 * Drops from Glow Squid.
 * Used to make Glow Item Frames and glowing signs.

je
 * Goat Horn.png Goat Horn
 * 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.


 * Powder Snow Bucket.png Powder Snow Bucket
 * Using a bucket on powder snow creates a powder snow bucket.
 * Powder snow buckets can be used to place powder snow.
 * Powder snow buckets can also be filled from cauldrons filled with powder snow.


 * Raw Iron, Raw Gold, and Raw Copper
 * Iron and gold ores now drop 1 raw iron and raw gold, as well as copper ore dropping 2-3 raw copper when mined instead of dropping themselves.
 * Can be smelted into their ingot variants.
 * The Fortune Enchantment works on iron and gold to drop more raw iron or raw gold.


 * Spawn Eggs
 * Spawn eggs for the new mobs are added.
 * Axolotl Spawn Egg JE1 BE1.png The axolotl spawn egg.
 * Glow Squid Spawn Egg JE1.png The glow squid spawn egg.
 * Goat Spawn Egg BE2.png The goat spawn egg.


 * Spyglass.png Spyglass
 * Crafted from an amethyst shard and 2 copper ingots.
 * When while held, it allows the player to see far away objects through a small square.
 * By pressing F1, the player can zoom in the whole screen; avoiding the border that is normally presented when using.
 * Switching to third person view while using the spyglass shows the player holding up the spyglass to where the eyes would be.

Mobs

 * Axolotl
 * Based on the Mexican salamander  in real life.
 * Planned to be found in bodies of water within lush caves biomes.
 * The first amphibian added to Minecraft.
 * Can be caught in a bucket like fish.
 * Comes in four common varieties, lucy (pink), wild (brown), gold, and cyan, and a rare blue variety, which has a $1/1200$ (~0.08334%) chance of spawning. This fraction is based on the fact that there are about 1200 axolotls left in the wild.
 * Plays dead when damaged, receiving Regeneration.
 * This regeneration ability is likely based on how real axolotls can regrow lost limbs.
 * Preys on fish, glow squid and squid, and attacks drowned and guardians (doesn't include Elder Guardians) if tempted with tropical fish by a player.
 * Axolotls prioritize hostile mobs over fish.


 * Glow Squid
 * Originates from the mob of the same name in Minecraft Earth.
 * Underwater mob that behaves like a regular squid.
 * Can spawn in underground water sources.
 * Is attacked by axolotls without provocation.
 * Drops glow ink sacs when killed.
 * Does not affect the light level, but appears as if lit up. Glows in the same way that magma cube cores, vexes, blazes and the eyes of spiders, drowned, and endermen do.
 * Stops glowing for a short time and swims away quickly after taking damage.
 * 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.


 * Goat
 * Spawns in mountain biomes.
 * Can jump high to avoid obstacles, about 5 blocks tall.
 * Attacks nearby mobs and players by charging and knocking them a considerable distance.
 * Mobs attacked by goats don’t attack back.
 * Doesn't attack ghasts or other goats.
 * Takes reduced fall damage.
 * Avoids powder snow by jumping over it.
 * Can be bred with wheat, which produces a baby goat.
 * Drops one goat horn when ramming into a block. Goat horns do not regrow.
 * Has a 2% chance of spawning as a screaming goat, with different sounds.
 * Screaming goats use their ramming attack more often than normal goats.
 * Drops nothing upon death.

Non-mob entities

 * Glow Item Frame.png Glow Item Frames
 * A variant of the Item Frame that is made using a Glow Ink Sac.
 * Appears to glow but does not give any actual light.

World generation

 * Amethyst Geodes
 * An underground cave-like feature.
 * Contains smooth basalt, calcite, blocks of amethyst, budding amethyst, and the amethyst clusters they generate.


 * Ore Veins
 * Large, rare, snake-like ore formations.
 * Copper ore veins mixed with granite generate above Y=0.
 * Iron ore veins mixed with tuff generate below Y=0.


 * Height dependent generation.
 * Revamped, featuring some new small spruce trees on the slopes and ice and packed ice above the peaks.
 * Contain goats, rabbits, snow blocks, snow layers and powder snow.
 * Iron ore, emerald ore and coal ore are found in abundance.
 * Emerald ore no longer generates in veins of only one.
 * Can generate up to Y = 260.
 * New sub biomes. Lofty Peaks, Snowcapped Peaks, Snowy Slopes, Stony Peaks, Grove, and Meadow.
 * New sub biomes. Lofty Peaks, Snowcapped Peaks, Snowy Slopes, Stony Peaks, Grove, and Meadow.


 * Caves
 * Completely overhauled.
 * Now stretch down to Y = -59.
 * The cavern now generates in 2 layers of different stone bases depending on the depth.
 * Cavern layer above Y = 0 is made up of regular stone.
 * Stone transitions to deepslate from Y = 0 to Y = -7.
 * Deepslate now completely replaces stone from Y = -8 to bedrock.
 * Biomes inside of caves introduced.
 * Contain aquifers, bodies of water or lava with different heights, independent of sea level (Y=63).
 * Improved old caves to blend in with the new generations of caves better.
 * New noise caves, coming in 2 forms, cheese and spaghetti.
 * Cheese caves have large stone towers stretching from the bottom of the cave to the top.
 * Very large, often large enough to fly with an elytra.
 * Abundant with aquifers and ores.
 * Spaghetti caves are long, thin caves that have small aquifers and are more similar to original caves.


 * Mineshafts
 * For support, in the air, can generate with log pillars below or chains on fence posts above.


 * Strongholds
 * Try to generate fully encased in stone at low y-levels.

Biomes

 * Contains pointed dripstone and dripstone blocks.
 * Generates larger blobs of Copper Ore
 * Generates larger blobs of Copper Ore


 * Contain cave plants and moss.
 * Moss covers the ceilings and floors.
 * Clay pools generate inside.
 * Clay pools generate inside.


 * 6 new sub-biomes added:
 * Similar to the plains biome but with a colder grass color
 * Contains most flowers and lone oak and birch trees.
 * Generates in plateaus and small mountains next to plains biomes
 * Covered in snow, snow blocks, dirt and powder snow, and is filled with spruce trees.
 * Rabbits, foxes and wolves spawn in this biome.
 * Generates in the slopes of a mountain when next to a forested biome
 * Covered in snow, snow blocks and powder snow.
 * Goats and rabbits spawn in this biome.
 * One of three mountain peak biomes that only generate if the mountain is high enough.
 * Generates in tall, jagged and pointy peaks.
 * Covered in snow, snow blocks and stone.
 * Only goats spawn in this biome
 * Generates in smoother and usually smaller peaks, but sometimes can generate in taller peaks.
 * Covered in snow and snow blocks with large patches packed ice and small blobs of ice.
 * Only goats spawn in this biome
 * Generates in mountain peaks in regions with warmer biomes such as savannas and jungles;
 * It's mostly covered by stone with strips calcite.
 * It doesn't generate snowy slopes or groves in the lower areas of the mountain.
 * Only goats spawn in this biome
 * Covered in snow and snow blocks with large patches packed ice and small blobs of ice.
 * Only goats spawn in this biome
 * Generates in mountain peaks in regions with warmer biomes such as savannas and jungles;
 * It's mostly covered by stone with strips calcite.
 * It doesn't generate snowy slopes or groves in the lower areas of the mountain.
 * Only goats spawn in this biome
 * Only goats spawn in this biome

Gameplay

 * An action can cause vibrations in the air, which can be picked up by sculk sensors and wardens.
 * Can be caused by player and mob movements, blocks being placed or broken, containers opening, projectiles being fired and landing, blocks like pistons moving, buttons, levers and pressure plates activating, and blocks activating. Vibrations are not caused by ambient weather such as rain or snow.
 * Can be caused by player and mob movements, blocks being placed or broken, containers opening, projectiles being fired and landing, blocks like pistons moving, buttons, levers and pressure plates activating, and blocks activating. Vibrations are not caused by ambient weather such as rain or snow.

General

 * Terrain
 * 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.
 * In Stone Shore and Stony Peaks, Diorite, Granite, Calcite, Andesite, and Gravel might of spawn in layers (strips) instead of splotches.


 * 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.


 * Ores
 * Most of the overworld ores have been retextured and touched up mainly for accessibility reasons. These also apply to the new deepslate ores.
 * This is a great help for color blind people that have difficulties distinguishing a certain ore of similar texture from another.
 * Diamond ore is an exception to this for being the "iconic" ore of the game, making Minecraft developers want to keep the classic feel of it.
 * Ore distribution has been changed for more strategic mining.
 * Certain ores are more common at certain depths, and some may generate in lower quantities or not generate at that level at all.

Blocks

 * Sculk.gif
 * Generates in the mysterious new cave biome where the Warden lives, called the Deep Dark.
 * Has an animated texture.
 * May be used in redstone.
 * Namespaced ID was revealed and found in the Bedrock Beta documentation. These blocks are currently not in the beta as it hasn't been implemented yet.


 * Sculk Catalyst.png
 * Generates in the Deep Dark cave biome.
 * Made of sculk and a bone-like material.
 * Sculk Catalyst (bloom).gif Has state.
 * May be used in redstone.
 * May have something to do with axolotls.
 * Glows, but does not emit light, similar to the glow squid or the glow item frame.
 * Namespaced ID was revealed and found in the Bedrock Beta documentation.


 * Sculk Shrieker.gif
 * Generates in the deep dark biome.
 * Perhaps made of sculk and a bone-like material.
 * Has 2 soul-shaped patterns in the center.
 * Has the ability to 'shriek' as revealed by internal textures.
 * Namespaced ID was revealed and found in the Bedrock Beta documentation.


 * Sculk Vein.gif
 * Generates in the Deep Dark cave biome.
 * Generates in a layer on top of blocks, similar to snow.
 * Can be placed in all directions, like glow lichen.
 * Has an animated texture.
 * Some have parts that are transparent, allowing the player to see the block it is on top of.
 * May be used in redstone as seen in this video when they talk about the sculk sensor.
 * Namespaced ID was revealed and found in the Bedrock Beta documentation.

Items

 * Warden Spawn Egg.png The warden spawn egg is visually confirmed but not yet implemented.
 * Warden Spawn Egg.png The warden spawn egg is visually confirmed but not yet implemented.

Mobs

 * Warden.gif
 * Spawns in the new Deep Dark cave biome.
 * The first fully blind mob (bats, despite relying almost exclusively on echolocation, still have basic eyesight).
 * When sensing movement, it moves toward the source of the movement.
 * Follows and attacks players, mobs, and other entities that make vibrations.
 * Does not attack other wardens.
 * Warden (angry).gif When attacked, it pathfinds toward the player.
 * Follows the same rules as the sculk sensor when detecting noise, apart from a much bigger detection range.
 * When it detects a vibration, the growths on its head rattle and light up, similar to the sculk sensor.
 * If any projectile (e.g. egg, snowball, arrow, splash potions, tridents) lands near the warden, the mob inspects the location where the projectile landed, due to the projectile creating movement and noise. This feature can be used in order to cause a distraction.
 * Does not detect players that are sneaking.
 * Can detect players that are invisible.
 * When aggravated for long enough, the warden follows the player continuously, regardless of any other distractions.
 * Does not follow music from a jukebox.
 * Investigates explosion noises.
 * Incredibly strong, doing damage, bringing players wearing full netherite armor from full health to  health points.
 * A mob designed to be extremely difficult to flee from, rather than fought against. Players are meant to sneak around the warden when traversing the Deep Dark, avoiding any vibrations that would cause it to detect them.
 * Has a way to counter the strategy of building up 4 blocks to avoid attacks.
 * At least as fast as the player's walking speed.
 * Seems to have considerable knockback resistance.
 * When near the warden, the brightness of the light the player sees decreases, regardless of Night Vision or brightness settings.
 * 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 3.5 blocks tall, making it one of the tallest mobs in the game, exceeding the iron golem and enderman in height and width (respectively).
 * This would also make it as tall as the wither (when hostile).
 * Currently burns in sunlight.
 * It is the only mob that spawns in the Deep Dark.
 * Does not spawn like normal hostile mobs, but instead uses completely new spawning rules.
 * The warden isn't needed to receive the advancement, Monsters Hunted.

World generation

 * biome
 * New biome at the "deepest depths of the world", exclusively generating within the deepslate layer.
 * Will be the rarest cave biome out of the three added in the update.
 * Generally found beneath very continental or mountainous areas.
 * Aquifers and lava are unlikely to generate in this biome.
 * Only wardens can spawn here.
 * Contains sculk blocks, sculk sensors, sculk shrieker, sculk veins, sculk catalyst.
 * May contain candles.
 * Contains chests.
 * Has official lore.


 * Ore generation further rebalanced, and influences the surrounding stone.
 * Ore generation further rebalanced, and influences the surrounding stone.

Gameplay



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

World generation
Blending


 * Helps make chunk borders less apparent by smoothing out borders between old and new terrain.
 * Replaces the old bedrock layer with deepslate and allows more caves and the deepslate layer to generate below.


 * Mineral veins
 * Some stone appears a little different and when that stone is mined, more of the ore should be found behind it.

Blocks

 * Sculk Trap (pre-release).png Jaw
 * Generates in the Deep Dark biome.
 * Sculk Trap 2 (pre-release).png Has state with unknown name.
 * May not make it into the final release.


 * Spore Blossom
 * Can close.


 * Azalea Log
 * Between Java Edition snapshots 21w05a and 21w10a, many blocks (flowers, leaves, grass, ferns, sweet berry bushes, small dripleafs) had a block tag called "azalea_log_replaceable", possibly implying the existence of azalea logs.
 * However, according to Jappa, the game’s artist, the reason azalea wood has not been added so far is because “Most colors of wood are currently covered. Azalea wouldn't be a special wood color like the nether woods. It would just be a slightly different color of another wood.” He also stated that “Adding wood is quite a lot of work. Azalea trees are also very singular and not in big forests, so finding a lot of azalea wood would be very hard.”

Java Edition

 * 1.17
 * 1.17.1 made changes to some game mechanics and fixes bugs.

Bedrock Edition

 * 1.17
 * 1.17.1 was released exclusively on Nintendo Switch to fix a bug in which players weren't able to connect to any server.
 * 1.17.2 was released to fix bugs related to world generation.
 * 1.17.10 added candles, brought additional parity with, experimental features for 1.18.0 and fixed bugs.
 * 1.17.11 was released to fix some critical bugs.
 * 1.17.30 was released to brought more additional parity with, new features behind the experimental toggle and fixed bugs.
 * 1.17.32 was released to fix some critical bugs after 1.17.30 release.
 * 1.17.33 was released exclusively on Amazon Fire devices to fix a bug in which players weren't able to launch the game.
 * 1.17.34 was released to fix a bug in which owned content did not appear in the inventory after redeeming a retail code.

Trailer
A trailer for Part I was released on June 8, 2021.

Showcases
Videos made by slicedlime:

Trivia

 * This is the first update:
 * To add a new ore to the Overworld since emerald ore was added in  for  and  for, in 2012 and 2014 respectively.
 * To add a real-world metal into the game since Classic 0.0.14a in 2009 for, which brought both iron and gold, and in 2012 for , which brought iron, not counting copper as an Element in Education Edition.
 * To add new shapes to cave generation since ravines were added in Beta 1.8 for and  for, in 2011 and 2014 respectively.
 * To add new types of rock to the Overworld since andesite, diorite and granite were added in Java Edition 1.8 and, both in 2014.
 * To completely overhaul the terrain generation since Java Edition 1.7.2 and Pocket Edition v0.9.0 alpha, in 2013 and 2014 respectively.
 * To be split $$ into two parts of development since the Adventure Update, which was split into Java Edition Beta 1.8 and Java Edition 1.0. $$, it is quite recent, the last split update being Village & Pillage.
 * To increase the world height (from 256 blocks to 384 blocks normally, with custom world generation generation up to 2048 blocks) since Java Edition 1.2.1.
 * To increase the depth of the bedrock floor underground since Java Edition Classic.
 * To add an amphibian mob to Minecraft.
 * To change the light level requirement for Overworld hostile mob spawning since Java Edition Indev.
 * To increase the cloud height since Java Edition Beta 1.8.
 * The name "Sculk" is derived from the word "skulk", meaning "keep out of sight, typically with a sinister or cowardly motive".
 * Mojang Studios employees explored real caves to research for the update. This helped give inspiration and ideas for the update, including for the mesh caves.
 * Henrik Kniberg also recalled memories of past visits to caves around the world.
 * The art style of the concept art for Caves & Cliffs was inspired by the concept art of Diamonds and Lemons, the Adventure Time episode featuring a Minecraft crossover.
 * Archaeology was originally planned to be added in this update, but was delayed to a later version when the update was split.
 * The warden was originally known as a "stalker" early during development. That iteration also had white flesh with holes in it, to the point where it was deemed too gory by the developers and had to be tuned down.
 * Brandon Pearce also mentioned that this is one of various "wildly different" iterations that he's going to preview once the warden is released to the public.


 * Trailer Trivia
 * At the 0:24 mark of the Caves & Cliffs: Part I trailer, the constellation can be spotted in the sky, which represents the sea-goat and is the Latin name for goat horn.
 * In the same trailer at 0:30 a Necromancer laugh from Minecraft Dungeons can be heard.

Gallery
Screenshots of the Caves & Cliffs Update from Minecraft Live 2020 and other sources: