Minecraft Wiki
13w21a Banner.png


Release date

May 23, 2013[1][2]

Snapshot for



Client (.json)

13w21a is the eighth snapshot released for 1.6.1.



  • 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


  • 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


12 bugs fixed

From released versions before 1.6.1

  • MC-1497 – Damaged Anvils do not show damage in inventory or item frame

From the 1.6.1 snapshots

  • MC-13626 – XP Bar in creative
  • MC-13640 – Hay Bales do not burn when set on fire
  • MC-13662 – XP, Health and hungerbar are buggy with horses
  • MC-13770 – Using a horse spawn egg on a horse works only when riding the horse
  • MC-13852 – Can’t throw enderpearls while mounting a horse
  • MC-14220 – Player appearance not updating in multiplayer (armor, tools)
  • MC-14417 – No way to remove armor or saddles off a horse
  • MC-14422 – Horse name tag is shown while riding
  • MC-15138 – Sides of cauldron has compass texture after placing compass in Item Frame
  • MC-15201 – Bottom part of some types of horses-harness is misplaced

From the previous snapshot

  • MC-15416 – Selected item disappears when armor breaks