Java Edition 13w21a

13w21a is the eighth snapshot released for 1.6.1.

Additions

 * Added a UI for horses and donkeys, to control saddle/armor/inventory
 * Can be accessed by sneaking and right-clicking, or by pressing the inventory button while riding the horse, mule, or donkey
 * Some features of the UI are specific to situation:
 * Horses, donkeys, and mules all have saddle slots
 * Horses have an armor slot
 * Donkeys and mules do not have an armor slot, but have an inventory of 15 slots when given a chest
 * New internal chat system; lots of messages should be translated now that were not previously

Changes

 * Started to move over various things to a new attribute system:
 * Item attributes using NBT tags:
 * Attributes can be additive, subtractive and multiplicative using a set value
 * Some items have default modifiers in place of previously hard-coded attributes
 * Examples of possible changes players could make: A bow that slows the holder, a helm that buffs health, etc.
 * Entity attributes:
 * These properties can now be changed as easily as any other NBT attribute
 * Entity speed, base health, base attack
 * Other properties like weapon damage/bow draw speed/sword swing speed are yet to follow
 * Added effect tooltips for some tools, swords, and potions
 * Lots of work towards a new Resource Pack system, but not finished yet. Currently still compatible with texture packs.
 * Messages are now better modularized
 * Server messages can be sent by their code-defined name, allowing the client to utilize the correct translation according to their language settings
 * Color can be specifically designated, preventing leakage into further messages
 * Horse armor is no longer stackable

Fixes
12 bugs fixed
 * – Damaged Anvils do not show damage in inventory or item frame
 * – XP Bar in creative
 * – Hay Bales do not burn when set on fire
 * – XP, Health and hungerbar are buggy with horses
 * – Using a horse spawn egg on a horse works only when riding the horse
 * – Can’t throw enderpearls while mounting a horse
 * – Player appearance not updating in multiplayer (armor, tools)
 * – No way to remove armor or saddles off a horse
 * – Horse name tag is shown while riding
 * – Sides of cauldron has compass texture after placing compass in Item Frame
 * – Bottom part of some types of horses-harness is misplaced
 * – Selected item disappears when armor breaks