Java Edition 16w21a

16w21a is the second snapshot released for Java Edition 1.10.

Command format

 * NBT Tags
 * Allows mobs to use elytra when they fall.
 * Mobs lose ability to fly after touching the ground.
 * Mobs lose ability to fly after touching the ground.

Blocks

 * Bone blocks
 * No longer transparent.


 * Dispensers
 * Can now equip shields onto entities.


 * Rails (all types)
 * Bounding box for ascending rails is a full block (formerly only $5/32$ of a block tall).


 * Structure block
 * No longer emit light.
 * Added "Structure Integrity and Seed" to load mode (NBT tags  and   respectively).

Items

 * Chorus fruit
 * Can now teleport riders from their mounts.


 * Ender pearls
 * Can now teleport riders from their mounts.


 * Fishing rod
 * Can now pull items to the player.

Mobs

 * Wolves
 * No longer despawn.

World generation

 * End portals
 * Now replace any blocks inside the portal frame ring when activating.


 * Villages
 * Blacksmiths now generate with cobblestone in all biomes (rather than acacia logs in savannas and sandstone in deserts).

Command format

 * NBT tags
 * and  tags now removed fully, replaced by the   first added in 16w20a.

General

 * Particles
 * now can be summoned, making use of the  argument like   and several other particles do.
 * Example: will summon a particle matching the color of lava (block 10).

Video
Video made by slicedlime:

Trivia

 * 16w21a was previously removed from the launcher for some time, but was added back in September 2018.