Java Edition 21w42a

This page covers a development version that has a major issue under certain conditions.

 

The dedicated server for this version has a security vulnerability in the Log4j library that could be used to perform a remote code execution exploit. It can be addressed by appending a certain JVM argument to the server startup command line.^[1]

Minecraft 21w42a

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21w42a is the sixth snapshot for Java Edition 1.18, released on October 20, 2021,^[2] which introduces new music, changes to world generation, and many fixes related to spawning.

Music disc

• Added the "otherside" music disc, composed by Lena Raine.
  • Can be found with a 2.5% chance in stronghold altar chests, or with a 3.1% chance in monster room chests.

Music

• Added new music to the Overworld (when playing in Survival mode), distributed to the new biomes, and to the main menu.^{[note 1]}
  • By Lena Raine:
    • "Stand Tall" plays in the snowy slopes, jagged peaks, frozen peaks and stony peaks biomes, as well as the menu screen.
    • "Left to Bloom" plays in the meadow and lush caves biomes, as well as the menu screen.
    • "One More Day" plays in the meadow, snowy slopes and lush caves biomes, as well as the menu screen.
    • "Wending" plays in the grove, jagged peaks, stony peaks and dripstone caves biomes, as well as the menu screen.
    • "Infinite Amethyst" plays in the grove and dripstone caves biomes, as well as the menu screen.
  • By Kumi Tanioka (谷岡 久美):
    • "Floating Dream" plays in the jagged peaks and lush caves biomes.
    • "Comforting Memories" plays in the grove biome.
    • "An Ordinary Day" plays in the snowy slopes, dripstone caves and lush caves biomes.

Options

• Added "Autosave Indicator" to video settings, for singleplayer worlds, which allows to toggle the indicator on / off.
  • The indicator appears in the bottom right of the screen whenever the game is saving the world file.
  • Defaults to on.

Particles

• Added block_marker, to replace light and barrier.
  • Renders with texture declared in particle slot for model assigned to configured block state.
  • Summoned with same syntax as block particle (i.e. block_marker wheat[age=2]).

Ore distribution

• Increased top height limit of badlands gold generation from Y=79 to Y=256, and increased the number of blobs.

Springs

• Lava springs can now generate amid calcite, dirt, snow, powder snow and packed ice.
  • These changes allow lava springs to generate in mountains and snowy terrain.
• Water springs don't generate higher than Y=192, and are slightly less common.

World spawn

• Reworked selection algorithm.
  • Now is selected according to the same climate parameters that control biome placement and world generation: players should no longer spawn in the ocean or some other inconvenient locations like certain mountain biomes.^{[needs testing]}

15 issues fixed

From released versions before 1.18

• MC-73300 – "Saving Level..." text not appearing in pause menu.
• MC-80824 – Spawning in some biomes causes "Unable to find spawn biome" warning.
• MC-129912 – Player no longer spawned at highest level at world spawn.
• MC-131686 – Spawn in ground with Buffet generation when creating a new world.
• MC-132347 – Spawning inside icebergs.
• MC-133466 – Certain world configurations force the player to spawn at X=8 Z=8.
• MC-185033 – Underground spawn in single biome world type.
• MC-185034 – Always respawning on the same block with no spawnpoint set.
• MC-198232 – Music plays less frequently as it normally did.
• MC-202166 – "Times Crafted" statistics column doesn't always display data correctly.
• MC-214288 – Player does not spawn on the surface of the world when min_y is greater than 0.
• MC-221641 – Caves can make ravines generate without water.
• MC-233771 – Parity issue: Light blocks do not display their light level when shown via a held light block item.

From the 1.18 development versions

• MC-236837 – The player can occasionally spawn underground when loading into a new world.
• MC-238582 – Beaches generate between desert and ocean.