Java Edition 21w06a

21w06a is the ninth snapshot for Java Edition 1.17, released on February 10, 2021, which adds new cave generation and a new build height limit.

World generation

 * Caves
 * Added aquifers and new noise caves, which come in two "flavors," 'spaghetti' and 'cheese' caves.


 * Spaghetti caves
 * Long noodle-like caves, sometimes wide like tagliatelle.


 * Cheese caves
 * Like the holes in swiss cheese, ofter form caverns of various sizes.


 * The old cave generation still generates, combining with the new caves.
 * The new generation also form cave entrances when they intersect with land.


 * Aquifers
 * Used to generate bodies of water in new caves. As of now, it's only used below y31, meaning any noise caves between the two heights are flooded with water. This will be fixed later.
 * Magma may generate at the bottom of these new water bodies.
 * Replaces the old underwater cave carvers/canyons.


 * Range
 * The generation and build limits range have now been increased in the overworld by 64 blocks in both directions.


 * Mineshaft
 * Mineshaft pieces no longer generate if they were fully floating in the air.
 * Corridors now generate with log pillars for support if needed.
 * There are no more floating cobwebs.

Blocks

 * Hanging Roots
 * The texture has been changed.


 * Small Dripleaf
 * The texture has been changed.

General

 * World
 * The Max height limit raised to 384 blocks.
 * The height limit now goes from -64 up to 320 blocks.

Trivia

 * Worlds created prior to this snapshot cannot be loaded in this version.