Java Edition 20w51a

20w51a is the fifth snapshot for Java Edition 1.17, released on December 16, 2020, which adds axolotls, a gamerule to control when night is skipped when sleeping, makes changes to the sculk sensor, and fixes bugs. This was the last snapshot released in 2020.

Items

 * Bucket of Axolotl
 * Obtained by right-clicking on an axolotl while holding a water bucket.
 * Spawn Egg
 * Added axolotl spawn eggs.

Mobs

 * Axolotls
 * Do not spawn naturally.
 * Are amphibious.
 * Will dry out and start taking damage after 5 minutes of being out of water.
 * Can be caught using a water bucket.
 * Are passive towards players.
 * Can be bred using tropical fish or buckets of tropical fish.
 * Come in five different colors: yellow, brown, white, pink, and blue.
 * Blue axolotls are very rare, with a $1/1200$ chance of spawning.
 * May play dead when damaged, receiving Regeneration I.
 * Attack drowned, guardians, squid and fish.
 * Are always hostile to fish and squid, and hostile to drowned and guardians only when "tempted" by a player holding tropical fish.

Command format

 * Controls what percentage of players must sleep to skip the night.
 * When set to 0 or a negative value, a single player is sufficient to skip the night, and night is skipped immediately without the falling asleep transition.
 * When set over 100, the night cannot be skipped.
 * Set to 100 by default.
 * Set to 100 by default.

General

 * Tags
 * Added the item tag.
 * Contains the tropical fish item and bucket of tropical fish.
 * Items in this tag can be used to tempt axolotls.
 * Added the item tag.
 * Contains the wool item tag.
 * As thrown entities, items in this tag do not trigger vibrations.
 * Added the entity type tag.
 * Contains tropical fish, pufferfish, salmon, cod, and squid.
 * Axolotls are always hostile towards entities in this tag.
 * Added the entity type tag.
 * Contains drowned and guardians.
 * Axolotls are hostile towards entities in this tag if they have been tempted.

Blocks

 * Sculk sensor
 * "Eating Start" has been removed as an event.
 * Walking on wool no longer causes vibrations.
 * Throwing wool as an item on the ground no longer causes vibrations.
 * Sculk sensors are now silent while waterlogged.

Items

 * Bundles
 * When destroyed as an entity, it drops the items it currently has.
 * Changed interface:
 * Now shows two empty slots when not full, and a X when full.
 * The first item in a bundle is now highlighted.


 * Shulker boxes
 * Like bundles, they drop their items when destroyed as entities.

General

 * Resource packs
 * Bundle icons are now a separate texture.


 * Tags
 * Removed the game event from the  game event tag.

Video
Video made by slicedlime:

Trivia
This snapshot was released on the second latest calendar out of all snapshots on December 16, only beaten by 15w51a and 15w51b on December 17.