1.21 - Ends and Beginnings

1.21, the Ends and Beginnings Update, is a major update to Java Edition released on July 11, 2023. The update was first announced at Minecraft Live 2022 alongside the 1.20 update. It focused on overhauling the End dimension with new terrain, blocks, items and structures, and also worked to improve inventory management and add new capabilities to datapacks.
This page will have all of the 1.21 features listed after the entire snapshot cycle has been completed.
== Experimental Snapshots ==
=== 1.21 Experimental Snapshot 1 ===
This experimental snapshot is the first experimental snapshot of Java Edition 1.21, released on January 16th, 2023, which introduced sweeping changes to the End dimension as well as numerous experimental technical changes. Worlds not created in this snapshot cannot be opened in this snapshot.
==== General ====
- Increased the number of inventory slots from 36 to 45.
- Increased the stack limit of most items to 128.
- Reintroduced the Bundle crafting recipe.
- Added experimental support for custom blocks and items to be added via datapacks.
* Custom blocks are added through data/namespace/blocks/block_name.json
* Custom items are added through data/namespace/items/item_name.json
* Several parameters for custom blocks and items are exposed, but are marked as experimental and are subject to change.
- Most blocks and items are now data-driven.
* Block entities, blocks with GUIs, and another "special" blocks are still hardcoded in this snapshot.
- Custom world generation in datapacks has been temporarily suspended,
* Developers confirmed this is a temporary measure during the experimental snapshots, and custom world generation in datapacks will return when regular snapshots begin.
- Increased datapack version from 10 to 11.
==== World Generation ====
- End dimension completely overhauled.
* Height limit was increased 256 blocks, with y=0 being the lower limit and y=512 being the upwards limit,
* End Highlands, End Midlands, End Barrens, and the Small End Islands biomes no longer generate. The End is the only biome in the dimension that generates, but developers confirm that the measure is temporary until the new end biomes can be implemented.
* Terrain generation stretches up from the previous limit of roughly 64 blocks up all the way to 448 blocks upwards.
* Terrain generation has been split into four main variants, which can be seen on the debug screen on the "NoiseRouter" line: Empty Void, Stacked Islands, Swirling Plateaus, and Floating Peaks.
=== 1.21 Experimental Snapshot 2 ===
This experimental snapshot is the second experimental snapshot of Java Edition 1.21, released on January 25th, 2023, which temporarily reintroduced some features of the End from before 1.21 Experimental Snapshot 1 and made some other minor changes. It was confirmed that regular snapshots would begin on February 1st, 2023. 
Worlds created in 1.21 Experimental Snapshot 1 cannot be opened in this version. 
==== General ====
- Blocks with GUIs and blocks with special functionalities are now data-driven.
- Moved data-driven blocks from data/namespace/blocks/block_name.json to data/namespace/block/block_name.json.
- Moved data-driven items from data/namespace/items/item_name.json to data/namespace/item/item_name.json.
==== World Generation ====
- End dimension height limit lowered 128 blocks from the previous snapshot, with the lower limit being y=0 and the upper limit being y=384 
- End Highlands biome has been renamed to Chorus Fields and has been reintroduced, mainly generating in Floating Peaks and Stacked Islands terrain. 
* This change also reintroduced End Cities.
** This makes all Purpur blocks, End rods, Shulker boxes, Dragon heads, and Elytras obtainable legitimately in survival once again.
== Snapshots ==
=== 23w05a ===
This snapshot is the first regular snapshot of Java Edition 1.21, released on February 1st, 2023, which added several End Update features, the /variable command, and more. Most of the technical changes and inventory changes from the experimental snapshots have been temporarily removed, set to be added back in a later snapshot. Worlds created before this snapshot can be opened in 23w05a, but the End dimension will be overwritten with the new generation. 
Custom world generation was also re-enabled this snapshot, and the pack format has been reverted to 10. 
==== General ====
- The stack size limit for most items is configurable via item tags. This is confirmed to be a temporary measure until data-driven items are reintroduced in a later snapshot. The tags are:
* #minecraft:unstackable
* #minecraft:stacks_to_16
* #minecraft:stacks_to_32
* #minecraft:stacks_to_64
* #minecraft:stacks_to_100
* #minecraft:stacks_to_128
** #minecraft:stacks_to_32, #minecraft:stacks_to_100, and #minecraft:stacks_to_128 are not used by any items by default.
- Reintroduced the Bundle crafting recipe.
==== Commands ====
- Added the /variable command.
* /variable (var) set value (number)
* /variable (var) add value (number)
* /variable (var) remove
- Added /execute cache, as temporary variable storage.
* Example syntax: /execute cache (var) value 1 run setblock 0 (var) 0
==== Blocks ====
- End Brick Chest
* Variant of the Chest.
* Currently replaces all Chests in End Cities.
* When opened and closed, it emits redstone power level 8.
- Chiseled End Bricks
* Currently unobtainable in Survival.
* Has a face resembling an Enderman on it.
- Chiseled Purpur Bricks
* Crafted using 2 Purpur Brick Slabs.
* Has a face resembling a Shulker on it.
- Purpur blocks
* Have been renamed to Purpur Brick blocks.
* Now have recipes in the stonecutter.
==== World Generation ====
- End dimension completely overhauled.
* Attempting to load an old world in this snapshot will result in the End dimension being overwritten.
* Height limit was increased 128 blocks, with y=0 being the lower limit and y=384 being the upwards limit,
* Terrain generation stretches up from the previous limit of roughly 64 blocks up all the way to 320 blocks upwards.
* Terrain generation has been split into four main variants, which can be seen on the debug screen on the "NoiseRouter" line: Empty Void, Stacked Islands, Swirling Plateaus, and Floating Peaks.
* End Barrens biomes no longer generate.
* End Highlands biome has been renamed to Chorus Forest.
* End Midlands biome has been renamed to End Flats.
* Small End Islands biome has been renamed to End Void.
* The End biome has been renamed to End Center.
- Added "New End Generation" density function: Is the only density function that controls new End generation. This is confirmed to be another temporary change for the End until terrain generation is almost complete.
=== 23w06a ===
This snapshot is the second snapshot of Java Edition 1.21, released on February 9th, 2023, which added more technical and inventory changes from the 1.21 experimental snapshots.
==== General ====
- Added experimental support for custom items to be add via datapacks.
* Custom items are added through data/namespace/item/item_name.json
* Several parameters for new custom items are exposed, but are marked as experimental and are subject to change.
- Increased the stack limit of snowballs, empty buckets, empty bottles, banners, eggs, signs, and armor stands to 64.
- Increased the stack limit of enchanted books with the same enchantments to 16.
==== Commands ====
- Added the /damage command from Bedrock Edition.
==== World Generation ====
- End generation changes.
* Worlds opened in this version will not have their end dimensions overwritten, but there will be no blending between old and new end generation.
* The center end island generation has changed. The terrain is much more rough, end spikes generate partially with crying obsidian, and the exit portal always generates at y=80.
* End Barrens has been renamed to End Wastes, and once again generates.
Category:Fan Made Updates
Category:1.20-1.24