Java Edition Classic 0.0.13a/Development

Several unreleased development versions of the game labelled 0.0.13a were developed on May 21st. They show in-development features later included in 0.0.13a and later releases. The huge world size features showcased in these versions would not be publicly available until 0.0.14a.

World size test (1) (May 21, 2009)

 * Additions
 * Added a thin black block selection outline.
 * Pressing Esc now opens the pause menu, with options to return to game, generate a new level and save/load level, the last of which doesn't do anything.
 * Changes
 * Game ratio is now 854×480, not 640×480.
 * The block being used is once again shown in the top right corner
 * Made swimming and sinking faster than before.
 * Holding the key no longer allows for autojumping.
 * Jump height reduced back to just over 1 block instead of just over 1.5 blocks.
 * This is the earliest version in the launcher where holding down R no longer causes the player to cycle between different locations - holding the key now has the same effect as simply pressing it.
 * Lava is no longer transparent and has a thick, red mist when underneath it.
 * Changed the texture of saplings from Oak Sapling JE1.png to Oak Sapling JE2.png.
 * The generated world is now completely flat. When generating a new level from the pause menu, the world will be of a long shape (512x64x32), but still flat. It is worth noting that caves can still generate in these worlds.
 * Trivia
 * This is the version available in the launcher, added to it among several other versions on August 6, 2013.
 * This is the only 0.0.13a developer build that is available in the launcher.

World size test (2) (May 21, 2009)

 * Changes
 * The world is now 1024x64x64 instead of 512x64x32 in size, and generates actual terrain.
 * Terrain has been updated to the 0.0.13a_03 format.
 * Dirt layer is now more uniform.
 * There is always a single block of dirt after grass and before stone.
 * If water generates next to lava on world generation, it will now produce stone.
 * Reference
 * Minecraft IRC logs, May 21, 2009
 * "(10:48:56) Notch_: and I just tried making a 1024x64x64 map. It's nuts [...] (10:49:06) Notch_: it's basically a looong gauntlet of hills and lakes"
 * Trivia
 * It is very likely this version has the new level generation screen, however this is not confirmed.

Huge levels (May 21, 2009)
YouTube video (reupload)
 * Changes
 * The world size is now 512x64x512.
 * Surface lava lakes still possible, as seen in the video.
 * The world generation screen has been changed.
 * The dirt background is now darker.
 * Added a progress bar below the progress text.