Java Edition 2.0

On April 1, 2013, Mojang released a hoax announcement post for Minecraft 2.0, a new game they had supposedly been working on for two years, describing how it would "bring blocky simulation games to the next level." The post also contained a changelog comprised mostly of nonsensical changes, such as a new half slab of TNT called Etho Slab.

Although lacking most of the promised additions, Minecraft 2.0 was produced and distributed to select celebrity individuals to showcase to the public as part of the joke. This version has not been released to the public. However, for a short period of time, players could download the game from assets.minecraft.net.

Downloads
The original files were hosted on assets.minecraft.net, but since then, many people have hosted the .jars. The "working links" below are mediafire links provided by Sacheverell, the Content Manager of MinecraftForum.net.

Changelog
Original hoax changelog: http://mojang.com/2013/04/its-finally-coming-minecraft-2-0/

New blocks

 * Etho Slab - Half-slab of TNT
 * As with other slabs, it can be placed on the upper half of a block space.
 * Same explosive and damage effect.
 * Spawns anvil above any players near the explosion.
 * Torch (Burnt-Out) - Torches burn out after a random amount of ticks.
 * Block of Coal - Craft with 3x3 coal.
 * Tinted Glass - Glass can be dyed any color that the dye exists for.

New mobs

 * Horse - Unlike the Horse that will be introduced in 1.6, these horses come in Shetland Pony (pig) and Horse (cow). Riding mechanics are the same as pigs, except that the full horse requires wheat to direct. The Shetland Pony drops Raw Porkchop, and the Horse drops Raw Beef.
 * Friendly Wither, or Pink Wither - Attracted to sugar, restores health to all surrounding mobs, and applies bone meal to all eligible neighboring blocks. It also has the ability to grow roses, dandelions, tall grass, and ferns on grass blocks, due to the bone meal. Starts off with one head, and feeding the Friendly Wither sugar will grow another head (up to three) and increase the range of these effects. If you want to spawn a Friendly Wither, you will need to place a pink wool, with a flower pot containing a rose on top. As with their evil counterpart, they drop Nether Stars. It is still classified as hostile mob, though its behavior is not hostile. The Friendly Wither is also considered undead, and will be hurt by potions of healing and healed by potions of harming. This is because the Friendly Wither has the same Mob ID as the Wither Boss. The Friendly Wither has no health bar.
 * Blue Chickens, or Diamond Chickens - Very rarely spawns instead of a normal chicken. Chance of laying diamonds or lapis lazuli instead of eggs. They do so at a much slower rate than normal chickens lay eggs. Explodes when aggravated.
 * Redstone Bug - Silverfish with color that is the same as the redstone they spawn over. No behavioral changes. Spawns when a redstone error is activated, on the spot of the error.

New features

 * Combining themes from YouTuber and MindCracker paulsoarsjr and the Legend of Zelda, Chicken are now a neutral mob, and will sometimes spawn reinforcements when killed.
 * You can feed sheep, pigs, horses, mooshrooms, and cows to make them fat. The tenth time they are fed they explode.
 * Using Golden apple on sheep makes them fly.
 * Some features that were not noted in the changelog are:
 * Mobs can have a rare chance of escaping fences and glass panes, and smaller mobs have a larger chance.
 * Blocks and mobs can talk using speech bubbles. Quotes include "You punched me!" "You mined me!" and "Mommy?" (Mummy? For people in the UK)
 * "Super Hostile Mode" is an occasional event, consisting of a shower of lightning bolts around the player (and usually striking the player at least once), while spawning a large number of powerful monsters in the area. These spawns include not only heavily armed and armored zombies and skeletons, and multiple charged creepers, but even the occasional Blaze and other unexpected monsters.
 * A new option for Super HD Graphics, which makes all textures monochrome except for recolored/secondary layer textures, such as grass side overlay.
 * Furnaces have a random chance (with each item smelted) of overheating (producing large amounts of smoke), and eventually exploding. The explosion is at least as powerful as a TNT block.
 * Torches burn out over time. They can be relit with Flint and Steel.
 * Droppers are renamed to floppers, and will change anything they drop to a fish. This is a GenerikB Reference, he said it in a video recently of MindCrack SMP.
 * Zombie Pigmen carry Battle Signs.

Bugs

 * Tinted glass has a bug where if on fast graphics, the bottom has some texture glitches when placed on any surface except Air.
 * You cannot see water through tinted glass, nor see tinted glass through water.
 * Mooshrooms spawn eggs spawn regular cows with mushrooms on their back.
 * Coal retrieved from Coal Blocks doesn't stack with normal coal, because it has a different data value (32767 as opposed to 0)
 * Using pick block on Tinted Glass only yields White Tinted glass due to a bug with the itemblock.
 * When the heat is not regulated in a furnace underwater, the furnace will still burn, smoke, and explode blocks underwater, setting blocks on fire underwater.
 * Because the horse is just a cow in horse skin, the horse still has udders.
 * There are no baby Diamond Chickens.
 * Iron Golems attack friendly withers.
 * You cannot sleep when there are friendly withers around.


 * When Endermen have an open mouth, and are behind Tinted Glass, the Tinted Glass becomes invisible.
 * Chickens don't have any fattening animation when fed, but will still explode as other mobs with the feeding mechanic.
 * Having both a wither and a pink wither will cause a 200% increase in frame rate. Mojang has promised it will be fixed soon.

Trivia

 * At 1:00 GMT, the splash text in 2.0 now will be huge and say APRIL FOOLS! in pink letters and obstruct the title menu.
 * Etho slabs (TNT Slabs) have a bigger explosion than TNT, although they are smaller than TNT.
 * Tinted glass uses filters.
 * Lightning can strike mobs through blocks.
 * The dropper's new name and functionality is a GenerikB reference, he said it in a video recently of MindCrack SMP.
 * The new Slab called Etho Slab is a reference to a YouTuber called EthosLab.
 * The Zombie Pigmen carrying Battle signs feature is a reference to Zisteau.
 * The regular Wither does not attack the Pink Wither, as they are classed as the same mob.
 * The easier the difficulty, the more challenging super hostile mode is.
 * In the game code, the Pink Wither is called WitherHug.
 * The "Super Hostile Mode" is a reference to Vechs' Super Hostile series of 'Complete The Monument' maps. Players must find colored wool to put on a Victory Monument. This is why some of the Mobs spawn with a random block of wool in their helmet slot, these mobs being known as 'Fleecy Mobs', which were the source of the wool in Vechs' Super Hostile map, 'Black Desert II'.
 * Friendly Withers seem to not have the ability to fly, unlike the normal Wither Boss.
 * The textures for Tinted Glass, Blue Chickens, and Redstone Bugs are all coded into the game, and are not found with the other mobs in the texture pack folders.