Java Edition 17w17b

17w17b is the ninth snapshot released for Java Edition 1.12.

General

 * NBT tags
 * , for breedable entities.
 * Together these record the UUID of the entity that caused a given animal to breed.


 * Advancements
 * Added a new number display to track progress while completing certain advancements
 * Added the  trigger
 * Takes two optional conditions:  and , both being strings that accept "overworld", "the_nether", or "the_end".
 * Without the conditions, you can check if the player travels to any dimension from any dimension.
 * The "location" shared object has a new  string (same values as above).

Mobs

 * Illusioners
 * The regional difficulty requirement for them to cast their Blindness spell is decreased from 3 to 2.

General

 * Advancements
 * The default advancements now all receive their titles and descriptions from the localization files.

Video
Video made by slicedlime:

Trivia

 * 17w17b was previously removed from the launcher for some time, but was added back in September 2018.