Minecraft:Java Edition 25w09a

25w09a is the eighth Minecraft:snapshot for Minecraft:Java Edition 1.21.5, released on February 26, 2025, which adds fallen trees for parity with Template:BE, updates firefly bushes to generate in more biomes and fixes bugs.<ref>Template:Snap</ref>

Additions

World generation

Minecraft:Fallen tree

• Fallen trees are a new decorative variant of trees.
• Fallen trees come in four different wood type variants:
  • Minecraft:Oak
  • Minecraft:Spruce
  • Minecraft:Birch
  • Jungle
• Birch fallen trees can come in a shorter version or a longer version.
• Some fallen trees can be decorated with Minecraft:mushroom or Minecraft:vines.
• Fallen trees can be found in all biomes where their standing tree variant grow, except the following:
  • Template:BiomeLink
  • Template:BiomeLink
  • Template:BiomeLink
  • Template:BiomeLink
  • Template:BiomeLink
    • Has fallen birch trees but not fallen oak trees.

Changes

Blocks

Minecraft:Dead bush

• Can now be placed on Minecraft:farmland.

Minecraft:Firefly bush

• The firefly bush can now generate near water in Minecraft:mangrove swamps and all types of Minecraft:badlands (very rarely), like other biomes with water.

Minecraft:Leaf litter

• Leaf litter is now replaceable by other blocks.

Minecraft:Short dry grass and Minecraft:tall dry grass

• Are now randomly offset within the block they are on.

Command format

Template:Cmd

• Can now create and modify heterogeneous lists transparently.
• Can no longer traverse paths with an empty key (e.g. Template:Cmd)

General

Minecraft:Block entity format

• campfire
  • The CookingTimes and CookingTotalTimes fields will no longer be preserved when removed.
• chiseled_bookshelf
  • The last_interacted_slot field now defaults to -1 if not specified.
• hopper
  • The TransferCooldown field now default to -1 if not specified.
• jigsaw
  • The name, target, and pool fields now default to minecraft:empty if not specified.
  • The final_state field now defaults to minecraft:air if not specified.
• sculk_shrieker
  • The warning_level field now defaults to 0 if not specified.
• structure_block
  • The ignoreEntities and showboundingbox fields now default to true if not specified.
  • The posY field now defaults to 1 if not specified.

Minecraft:Data pack

• The Minecraft:pack format version is now 69.
• New command line argument --renderDebugLabels is available for the client.
  • Adds debug labels to relevant OpenGL objects, making debugging rendering easier for developers.

Minecraft:Entity format

• The FallFlying field will no longer be preserved if removed.
  • The Health and Air fields now default to their respective maximum value if not specified.
• area_effect_cloud
  • The Duration field now defaults to -1 if not specified.
  • If the Duration field is -1, the Area Effect Cloud will never run out.
  • This means that an Area Effect Cloud summoned with no duration specified will no longer immediately disappear.
• creeper
  • The Fuse field now defaults to 30 if not specified.
  • The ExplosionRadius field now defaults to 3 if not specified.
• dolphin
  • The Moistness field now defaults to 2400 if not specified.
• ender_dragon
  • The DragonDeathTime field now defaults to 0 if not specified.
• falling_block
  • The BlockState field can now be air (will despawn immediately) - if otherwise not specified or invalid, defaults to sand.
  • The HurtEntities field now defaults to false if not specified (or true if BlockState is anvil).
  • The FallHurtAmount field now defaults to 0 if not specified.
  • The FallHurtMax field now defaults to 40 if not specified.
  • The DropItem field now defaults to true if not specified.
  • The TileEntityData field will no longer be preserved if removed.
• firework_rocket
  • The ShotAtAngle field now defaults to false if not specified.
• fox
  • The Trusted field now defaults to empty if not specified (and will no longer be merged with the previous state if modified by Template:Cmd).
• ghast
  • The ExplosionPower field now defaults to 1 if not specified.
• goat
  • The HasLeftHorn and HasRightHorn fields now default to true if not specified.
• interaction
  • The width and height fields now default to 1 if not specified.
• item
  • The Health field now defaults to 5 if not specified.
  • The PickupDelay field now defaults to 0 if not specified.
  • The Age field now defaults to 0 if not specified.
  • The Owner and Thrower fields will no longer be preserved when removed.
• item_frame and glow_item_frame
  • The ItemDropChance field now defaults to 1.0 if not specified
• primed_tnt
  • The fuse field now defaults to 80 if not specified.
  • The explosion_power field now defaults to 4 if not specified.
• shulker
  • The Color field now defaults to 16 (no color) if not specified.
• skeleton
  • The StrayConversionTime field will no longer be preserved when removed.
• spectral_arrow
  • The Duration field now defaults to 200 if not specified.
• snow_golem
  • The Pumpkin field now defaults to true if not specified.
• tnt_minecart
  • The fuse field now defaults to 80 if not specified.
  • The explosion_power field now defaults to 4 if not specified.
  • The explosion_speed_factor field now defaults to 1 if not specified.
• trader_llama
  • The DespawnDelay field now defaults to 47999.
• villager
  • The FoodLevel and Xp fields now default to 0 if not specified.
  • The ConversionTime field will no longer be preserved when removed.
• wandering_trader
  • The DespawnDelay field now defaults to 0 if not specified.
• zombie
  • The DrownedConversionTime field will no longer be preserved when removed.
• zombie_villager
  • The Xp field now defaults to 0 if not specified.
  • The ConversionTime field will no longer be preserved when removed.
• arrow, spectral_arrow, trident
  • The damage field now defaults to 2 if not specified.
• dragon_fireball, wind_charge, breeze_wind_charge, wither_skull, small_fireball, and large_fireball
  • The acceleration_power field now defaults to 0.1 if not specified.
• small_fireball and large_fireball
  • The ExplosionPower field now defaults to 1 if not specified.
• block_display, item_display, and text_display
  • The interpolation_duration, teleport_duration, and start_interpolation fields now default to 0 if not specified.
  • The view_range field now defaults to 1 if not specified.
  • The shadow_radius field now defaults to 0 if not specified.
  • The shadow_strength field now defaults to 1 if not specified.
  • The width and height fields now default to 0 if not specified.

Minecraft:NBT format

• Any interface with NBT data within the game (SNBT representation, Template:Cmd) now supports heterogeneous lists, i.e. ones where elements are not of the same type
  • Inserting or replacing into a list of a different type with Template:Cmd will no longer give an error.
  • Inserting into an array type (e.g. [I;1,2,3]) is still type-restricted.
  • This means that the 'wrapper' objects previously used to represent heterogeneous lists will no longer be observable by in-game means.
• The NBT file format is unchanged.
  • Heterogeneous lists are transformed before storage to bypass NBT constraints.
    • Example transform: ['a', {'b':3}] is stored as [{'':'a'},{'b':3}].
  • Existing external tools will still be able to read NBT files as before, but heterogeneous lists will be displayed in the transformed form.
• No data produced by the game has changed: objects such as Text Components were already producing heterogeneous lists in this form.
• Note: these wrapper objects may never be observed in-game, they are only relevant to developers working with the NBT file or network format directly.

Minecraft:SNBT format

• The text format for describing object-like data in commands (like NBT, text components, predicates, etc.) has been extended.
• Number Format
  • Either whole or fraction parts of a float number can be omitted
    • Examples: .1 and 1. are valid now
  • Float numbers now use E notation
    • Example: both 1.2e3 and 1.2E3, 1.2E+3, 12000e-1 are now a valid way to represent 1200.0
  • Integer numbers can now be prefixed with 0x to represent hexadecimal numbers and 0b to represent binary numbers
    • Example: 0xbad (equal to 2989), 0xCAFE (equal to 51966), 0b101 (equal to 5)
  • Integer numbers now can't start with 0
    • Normally (e.g. in Java) it would mean number is in base-8, but this usage is not implemented, to avoid accidental misuse
  • Numbers can now contain _ character between sequences of digits (but not at the start or the end of sequence)
    • Example: 0b10_01, 0xAB_CD, 1_2.3_4__5f, 1_2e3_4
  • NaN, Inf or hexadecimal float representation are NOT supported
  • Type suffixes have been extended:
    • Integer type suffixes (b or B - byte, s or S - short, i or I - integer, l or L) can now be prefixed with s (signed) or u unsigned
    • New suffixes only affect valid range when parsing - values are still stored as signed
      • Example: 240ub is equal to -16sb, while 240sb does not parse
    • When a suffix is used without u or s, it defaults to signed for decimal numbers and unsigned for binary and hexadecimal numbers
    • Note: since b is also a valid hexadecimal digit, byte sized hexadecimal values can only be written with a signed suffix, like 0x11ub or 0x11sb

• Strings
  • Quoted strings can now use escape sequences beyond ', " and \:
    • Unicode escapes:
      • \x - two digit escape, like \x42
      • \u - four digit escape, like \u2603
      • \U - eight digit escape, like \U00002603
      • \N{<name>} - named Unicode character, like \N{Snowman}
    • Built-in escape sequences:
      • \b - backspace, Unicode \x08
      • \s - space, Unicode \x20
      • \t - horizontal tab, Unicode \x09
      • \n - linefeed, Unicode \u0a
      • \f - form feed, Unicode \u0c
      • \r - carriage return, Unicode \u0d
  • Unquoted strings now can't start with 0-9, ., +, - to avoid accidental collision with numbers

• Number Arrays
  • Values in arrays ([B;], [I;], [L;]) without a suffix are now assumed to have suffix matching the type of the array
    • Example: [B;1,2] is equivalent to Template:Cd
  • Arrays can now also accept types smaller than the array type
    • Example: [I;1b,2s,3] is valid and equivalent to [I;1i,2i,3i]

• Lists
  • Lists now accept trailing commas
    • Example: [1,2,] is valid and equivalent to [1,2]
    • Only one trailing comma is allowed, and it must come after a valid element - both [,] and [1,,] are invalid

• Compounds
  • Compounds (maps) now accept trailing commas
    • Example: {a:b,}
    • Only one trailing comma is allowed, and it must come after a valid key-value pair - both {,} and {a:b,,} are invalid

Minecraft:Tags

• Added farmland to #dry_vegetation_may_place_on block tag.
• Added leaf_litter to #replaceable block tag.
• Added cactus_flower to #wall_post_override block tag.