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 to 
** The generated world is now completely flat. When generating a new level from the pause menu, the world will be of a long shape (32x64x512), 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 512×64×512.
** Surface lava lakes are 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.
==Gallery==
Classic 0.0.13a.png|A screenshot of World size test 1.
Classic 0.0.13a-dev1 long world.png|A long flat strip of grass block.
Dinnerbone 0.0.13a.png|Screenshot of this version from Dinnerbone.
Category:Unreleased builds
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