Java Edition 12w07a

12w07a is the sixth snapshot released for 1.2.1.

Additions

 * World file format changed to format called Anvil.
 * World height is now 256 blocks instead of 128 blocks.
 * Up to 4096 block IDs can be used.
 * Added Redstone Lamp.
 * If powered by redstone, the lamp will turn on
 * Crafted using glowstone and redstone

Changes

 * Multiplayer light calculations no longer cause affected blocks to be transmitted to the clients, instead the clients will recalculate the light on their own.
 * This means that chunk errors can not be fixed by placing a torch anymore
 * Villagers will repopulate villages based on how many houses there are available.
 * The player may add houses to villages, provided they are enclosed with a roof and wooden door.
 * Some nights in villages will be worse than others. Referring to Zombie Invasions
 * Decreased chance for the rare mob drops.
 * All animals use the new AI system now.
 * Animals can now move their heads when walking.
 * Baby animals will now follow wheat.

Fixes
2 bugs fixed


 * Fixed wolf AI (They no longer teleport huge distances when the player is hit).
 * Fixed Zombies breaking iron doors.