Java Edition 21w13a

21w13a is the fifteenth snapshot for Java Edition 1.17 released on March 31, 2021, which adds goats, light blocks, and makes tweaks to caves and ore blob generation.

Blocks

 * Light Block
 * A new waterloggable source of light, originally was a Bedrock Edition exclusive.
 * Behaves like air, and it is visible and targetable only when the item is held, similar to barriers.
 * Obtainable only with.
 * Right-click cycles light level.

General

 * Added an alternative solid black background color for the Mojang Studios loading screen, toggleable with the “Monochrome Logo” accessibility option.

Mobs

 * Goat
 * Spawn in Mountains.
 * Jump higher than regular mobs.
 * Can be tempted and bred using Wheat.
 * A bucket can be used to get milk.

World generation

 * Made carvers less likely to be too flat to walk through.
 * Increased likelihood of megacaves (large cheese caves).
 * Reduced likelihood of toothpick pillars (tall 1-block thin pillars).
 * Other tweaks to make the cheese caves more varied.
 * Deepslate blobs can now be found between heights 0 and 16.
 * Dripstone clusters can now be found rarely in normal caves.
 * Slightly more iron.
 * Larger diamond blobs sometimes form.

Structures

 * Increased the max length of pillars and chains on Mineshafts.

Mobs

 * Axolotl
 * Axolotls now spawn in underground water sources
 * Axolotls will now always chase after and attack squids, glow squids, tropical fish, cod, salmon, pufferfish, drowned, guardians, and elder guardians
 * Axolotls now have a two-minute cooldown after hunting non-hostile targets such as fish, squids, etc.
 * They will prioritize targeting hostile mobs first before hunting.


 * Glow Squid
 * Glow squids now spawn in underground water sources.


 * Bee
 * Bees now see Flowering Azalea (and Flowering Azalea Leaves) as flowers.


 * Wandering Trader
 * Added the following trades to Wandering Trader:
 * Will sell 2 Pointed Dripstones for 1 emerald.
 * Will sell 2 Rooted Dirt for 1 emerald.
 * Will sell 2 Moss Blocks for 1 emerald.


 * Mason
 * Added the following trade to Mason:
 * Will sell 4 Dripstone blocks for 1 emerald.


 * Stray, Polar Bear and Snow Golem
 * Are now immune to freezing.


 * Blaze, Magma Cube, and Strider
 * Take increased freeze damage.


 * Skeleton
 * Skeletons converting to strays now only require the 7 seconds it takes for an entity to be fully frozen to begin converting, instead of the 30 seconds it took before.

Blocks

 * Powder Snow
 * Powder snow’s durability/hardness was slightly increased.
 * Freeze time has decreased to 7 seconds and hurt frequency has decreased to 2 seconds.
 * Entities on fire now melt Powder Snow when colliding.
 * Increased vertical movement speed within Powder Snow.
 * Mobs now shake when they are fully frozen.


 * Candle
 * Candles can now be extinguished by splash water bottles and by lingering water bottles.

Items

 * Leather Horse Armor now protects horses from freeze damage.

Loot tables

 * Additions to chest loot tables:
 * Moss blocks can be found in Shipwreck chests.
 * Glow Berries can be found in Mineshaft chest minecarts.

Technical

 * Unused parts of code (unused static fields and methods) are no longer removed.
 * Although this does not affect the game itself, adds more info for modders.