Java Edition 15w34a

15w34a is the tenth snapshot released for 1.9.

This version was previously removed from the launcher for some time, but was added back in September 2018.

Command format

 * NBT tags
 * Added the  and   byte tags to   tile entity for command blocks.
 * Added the  (Integer) and   (List/Double) tags to.
 * Added the  string tag inside   for the   tile entity.
 * Added the  byte tag to   tile entity for note blocks.

Blocks

 * Command blocks
 * New textures that now vary depending on what direction they are placed from, similar to dispensers and pistons.
 * It consists of a front, a back and a side texture (looks like arrows), so the orientation can be easily determined.
 * The texture is animated - the colored "buttons" in the middle change color.
 * The middle panel texture has a black outline.
 * 3 modes: impulse, chain, and repeat - color changes based on mode.
 * Impulse mode (orange): Command is run once on rising edge.
 * Same behavior and color as previous versions.
 * Chain mode (green): Command is run whenever another command block pointing into it executes, and the command block in question is powered.
 * The chain signal is forwarded until the blocks get out of loaded chunks.
 * The signal is independent of the powered state of any block in the chain, as well as the command (or lack thereof) inside.
 * Repeat mode (blue): Command is run every game tick while powered.
 * Like a minecart with command block but faster.
 * Each new mode has its own block id and is obtainable with and.
 * Power received is now a data tag, allowing command blocks to have such a state under control, independent of any nearby redstone signal.
 * Command block contraptions from earlier versions will still work.
 * The "Done" button is now always available to press, even when the command line is empty.


 * Note blocks
 * Their power state is controlled through a tag, and can, therefore, be controlled independently on any redstone signal.

Items

 * Maps
 * Now start at a wider zoom level (1:4 instead of 1:1).
 * New recipe for zooming in on a map: Shears and a map together in any shape.
 * Zooms in on the lower-right quadrant of the original map.
 * This causes the shears to lose durability.

Mobs

 * Zombies and zombie pigmen
 * Now lift their arms slightly when becoming hostile.

Non-mob entities

 * Minecarts with command blocks
 * The "Done" button is now always available to press, even when the command line is empty.

Command format

 * NBT tags
 * for the  block entity has been deprecated.

Gameplay

 * Combat
 * New attack speed combat mechanic.
 * A meter shows up after switching items or attacking.
 * Damage done depends on the fullness of the meter.
 * Fills in 0.25s for non-weapons, 0.8s for swords, pickaxes, and shovels, and 1.2s for axes.
 * The meter can be displayed next to the hotbar (left or right based on the player's main hand), under the crosshair or turned off.
 * Looks like the icon for the effect on the side of the hotbar, or like a dagger under the crosshair.
 * This is controlled in video settings.
 * Delay when selecting a sword, pickaxe, axe or shovel into the main hand.

General

 * Optimizations
 * Optimized mob AI, pathfinding and block ticking.
 * 15% tick speed increase on 16 render distance.

Video
Video made by slicedlime: