Java Edition 17w50a

17w50a is the eleventh snapshot released for 1.13, and the final snapshot released in 2017.

Command format

 * Added a new local coordinate type in commands using.
 * When specifying coordinates in a command, you can now use  to specify local coordinates instead of world coordinates.
 * The axes used for local coordinates are relative to the rotation of the executing entity.
 * Like world coordinates, they are measured from the base of an entity.
 * The syntax is:
 * is the amount of blocks in the specified direction.
 * For example, typing in chat will set a stone block 3 blocks in front of you in your view.
 * Tab-completing coordinates when not targeting a block will suggest  again.

General

 * Tags
 * Added the default tags  and   for both items and blocks.
 * The tags  and   now include   and   respectively for both items and blocks.

Blocks

 * Item frames
 * Item frames can now be placed on the top and bottom of blocks.

General

 * Tags
 * Tags can now include other tags (of the same type).
 * You can add for example  in a tag value list to reference another tag called.
 * Self referencing is not possible.
 * When overriding a tag, you can now choose to replace instead of append.
 * By default all tags append if another data pack created the tag.
 * Adding  to your tag definition will make that tag replace existing tags instead.
 * When used in commands, block tags now support block state and data tag arguments.

Video
Video made by slicedlime:

Trivia

 * Unlike most first-of-the-week snapshots up to this point, this was released on a Monday instead of Wednesday, similar to 17w48a.