Java Edition 13w18a

13w18a is the fourth snapshot released for 1.6.1.

Additions

 * Added Block of Coal.
 * Crafted with coal in a 3x3 space.
 * The block cannot be crafted with charcoal.
 * Can be used as furnace fuel and smelts 72 items, the equivalent to 9 coal.
 * Can be used as a storage block for large amounts of coal, similarly to blocks of iron and related blocks.
 * Start of a new texture loading system.
 * New "missing texture" texture.
 * Added crafting recipes for leads and hay blocks.
 * Hay blocks are crafted with wheat similarly to mineral blocks.
 * Hay blocks cannot be crafted back into wheat.
 * Added chest generation in Nether Fortresses.
 * Chests generate in corners of interior corridors

Changes

 * Locked Chests texture changed again.
 * Tweaked horse equipment obtainability.
 * Players can no longer craft horse armor.
 * Horses now use the same saddle that pigs use.
 * Saddles can now be found in most generated chests.
 * Added horse armor to dungeons.
 * Removed Horse Saddles.
 * Normal saddles are now required to ride horses.
 * Adjustments related to horses makes them more practical later in the game.
 * Redstone Comparators now output a signal for cauldrons and end portal frames.
 * A cauldron gives signal strengths that range from zero (empty) to three (full) depending on the amount of water contained inside.
 * An end portal frame would give a signal strength of either zero or fifteen, depending on if an eye of ender has been inserted into it.
 * Mechanic whereby zombies spawn more zombies adjusted to be subtle and not as easily visible to the player.
 * Zombies spawn in dark areas far from the player or in caves.
 * Carpets can now be placed on translucent blocks.
 * This includes glowstone, glass, glass panes, and beacons.
 * Beacons will still function under carpet.
 * Cocoa beans removed from dungeon chests.

Fixes
7 bugs fixed

From released versions before 1.6.1
 * – Mobs not realizing they killed their attacker and trying to attack empty space
 * – Dogs wont stop snarling after punched by someone else
 * – Despawning cured zombie
 * – Lava decay fails to schedule block update
 * – Blocks stop updating one minute after entering the Nether or the End

From the 1.6.1 snapshots
 * – You can pick up command blocks with any pickaxe

From the previous snapshot
 * – Can't place carpet on translucent blocks