Last week, Minecraft released the first snapshot for the upcoming Mounts of Mayhem game drop, featuring the nautilus, nautilus armor, spear, a new enchantment, and more. Like after every major snapshot, today's Minecraft snapshot 25w42a is more about bug fixes discovered by the community during a week of testing. Along with tons of bug fixes, Minecraft snapshot 25w42a includes some useful changes and interesting technical features. In the last snapshot, Mending was incompatible with the Lunge enchantment, which was problematic because the new enchantment consumed too much durability. Mojang has now made both enchantments compatible with each other. Mojang also introduced Environment Attributes in the latest snapshot, allowing modders to make changes to dimensions, biomes, and many other visual and gameplay systems more easily than before. Read the complete Minecraft snapshot 25w42a patch notes below to find out what's new.Minecraft snapshot 25w42a patch notesChangesUnderwater biome fog color and fog distance is now blended based on the player's position between biomes, similarly to regular biome fog and sky colorsUpdated the "Oh Shiny" advancement to include the Golden Spear and Golden Nautilus ArmorZombie Horses can be leashed when its mob jockey is removedThe Nautilus and Zombie Nautilus can now be controlled while on landMending is no longer incompatible with the Lunge enchantmentTechnical changes in Minecraft snapshot 25w42aThe Data Pack version is now 90.0The Resource Pack version is now 70.1Minecraft Server Management Protocol Version 1.1.0Enable authentication from web browsersAuthenticate by passing the token in Sec-WebSocket-Protocol header when opening the WebSocket connectionExample: Sec-WebSocket-Protocol: minecraft-v1, <token>Requests authenticating this way are subject to Origin header checks. This requires configuration of allowed origins on the server side using management-server-allowed-origins. The default value is empty, meaning Sec-Websocket-Protocol authentication is effectively disabledData Pack Version 90.0Certain visual and gameplay effects can now be controlled by Environment AttributesCommandsResource suggestions now show results in any namespace instead of just within minecraftChanged stopwatchSwitched the order of the id argumentExample: /stopwatch foo:bar create is now /stopwatch create foo:barquery now returns the queried value and takes in a new scale argumentThe returned value will be scaled by that argument and truncatedThe scale is optional and will default to 1 if omittedExample: /stopwatch query foo:bar 20 to get the elapsed time in ticksEnvironment AttributesEnvironment Attributes provide a data-driven way to control a variety of visual and gameplay systems.Each Environment Attribute controls a specific visual or gameplay effect: for example, minecraft:visual/sky_color controls the color of the sky, and minecraft:gameplay/water_evaporates controls whether water can be placed at a given location.Developer’s Note: This system and many of the introduced attributes should be considered very experimental, and may still change significantly in coming snapshots and releases. In the meantime, we would as always love to hear any feedback or suggestions you may have!SourcesEnvironment Attribute values can be provided by the following Environment Attribute sources (in order of low to high priority):DimensionsBiomesThe "effective" value of the Environment Attribute (i.e. what will actually show up in game) will be some combination of the values provided by each source according to their priority.For example, in the following scenario:The overworld dimension provides sky_color = #00ff00 (green)The plains biome provides sky_color = #ff0000 (red)When the player is in the plains biome, they will see the red sky_color, while anywhere else in the overworld they will see green.When an Environment Attribute source provides an Environment Attribute, it can:Override the value, such as the plains biome overriding the overworld's sky_color in the above scenarioApply a modifier to a previous value (see section on Modifiers below)ModifiersAs described in the above example, an Environment Attribute source may simply override the value of a particular attribute. However, it is sometimes also desirable to rather apply a modifier to a value provided by a source with lower priority.For example, in the following scenario:The overworld dimension provides water_fog_radius = 96.0The plains biome modifies water_fog_radius with a multiply modifier of 0.85When in the plains biome, the water_fog_radius will be resolved to 96.0*0.85 = 81.6, while in any other Overworld biome, it will resolve to 96.0.The kinds of modifiers available depends on the type of Environment Attribute. The most basic modifier, supported by every Environment Attribute, is the override modifier. This behaves purely as an override of the preceding value. If not specified by an Environment Attribute source, the modifier will always be assumed to be override.Full descriptions of the available modifiers and their behaviors can be found in the Common Modifiers section below.InterpolationWhile modifiers describe how a value provided by one source is applied on the value from a preceding source, interpolation describes the combination of values within a source. Interpolation is performed on values from a source after modifiers have been applied.Only some Environment Attributes support interpolation. This allows for the smooth transition between two or more values, such as when moving between two biomes.BiomesFor example, in the following scenario:The plains biome provides sky_color = #ff0000 (red)The desert biome provides sky_color = #ffff00 (yellow)sky_color is one such attribute that will transition smoothly based on position: for example, in the above scenario, as a player moves from a plains to a desert biome, the sky color will gradually shift from red to yellow. Other attributes, such as water_evaporates, represent discrete values and will not be smoothly transitioned - only the biome exactly at a subject position will be considered.Smooth transitions between biomes are based on the biomes within an 8 block radius of the camera. Biomes that occupy a larger portion of that radius and are closer to the camera will have a stronger influence on the final interpolated value.Environment Attribute MapDimension Type and Biome definitions contain a new attributes field, enabling them to define Environment Attributes.This map generally takes the form of an object mapping between Environment Attribute IDs and their corresponding values, for example:"attributes": {"minecraft:visual/fog_color": "#ffaa00","minecraft:gameplay/water_evaporates": true}Values defined as above will always be assumed to use the override modifier.The value object can however be expanded in order to express different modifiers, in the format of an object with the following fields:modifier: optional string modifier ID, dependent on the Attribute Type (see the Common Modifiers section below)Default: overrideargument: the modifier argument (format dependent on the chosen modifier)How the argument is used also depends on the type of modifierFor example, the following definition describes multiplying water_fog_radius by 85%:"attributes": {"minecraft:visual/water_fog_radius": {"modifier": "multiply","argument": 0.85}}Common Data TypesThe following data types are reused in various parts of the Environment Attributes system and will be referenced in sections below.RGB ColorFormat can be one of the following:A hex color RGB string, in the form #rrggbbA float array with 3 components, between 0 and 1, in the form [r, g, b]An integer in packed RGB formARGB ColorFormat can be one of the following:A hex color ARGB string, in the form #aarrggbbA float array with 4 components, between 0 and 1, in the form [a, r, g, b]An integer in packed ARGB formParticle OptionsA full definition of a particle, including any type-specific properties (as in the /particle command).For example:{"type": "minecraft:block_crumble","block_state": {"Name": "minecraft:dirt"}}Common ModifiersEvery Environment Attribute has a specific value type, which describes how values must be defined as well as what modifiers are available and how they are interpolated. Some are very specific, while others are reused across many attributes.Although this is not an exhaustive list, the following Attribute Types are used commonly across many Environment Attributes:Modifiers on Boolean ValuesArgument format: booleanoverrideandnandornorxorxnorModifiers on Float ValuesArgument format: floatoverrideaddsubtractmultiplyminimummaximumModifiers on Color ValuesArgument format: RGB color (except alpha_blend)overrideadd - component-wise additive color blendingsubtract - component-wise subtractive color blendingmultiply - component-wise multiplicative color blendingalpha_blend - traditional alpha blending that might be seen in image editing softwareArgument format: ARGB ColorWhen the argument alpha is 1, it will behave as an override with no blendingNew Environment Attributesminecraft:visual/fog_colorThe color of fog (when the camera is not submerged in another substance). Note: the final value is also affected by the time of day, weather, and potion effects.Value type: RGB colorDefault value: #000000Modifiers: Color ModifiersInterpolated: yesResolved at the camera's positionReplaces Biome effects.fog_color fieldminecraft:visual/extra_fogControls whether dense fog (like that of the Nether) should be used (when the camera is not submerged in another substance).Value type: booleanDefault value: falseModifiers: Boolean ModifiersInterpolated: noResolved at the camera's positionminecraft:visual/water_fog_colorThe color of fog when submerged in water. Note: the final value is also affected by the time of day, weather, and potion effects.Value type: RGB colorDefault value: #050533Modifiers: Color ModifiersInterpolated: yesResolved at the camera's positionReplaces Biome effects.water_fog_color fieldminecraft:visual/water_fog_radiusThe distance in blocks from the camera at which underwater fog reaches its maximum density.Note: the final value is also modified by how long the player has been underwater.Value type: non-negative floatDefault value: 96.0Modifiers: Float ModifiersInterpolated: yesResolved at the camera's positionReplaces #has_closer_water_fog Biome Tagminecraft:visual/sky_colorThe color of the sky. This color is only visible for the overworld sky. Note: the final value is also affected by the time of day and weather.Value type: RGB colorDefault value: #000000Modifiers: Color ModifiersInterpolated: yesResolved at the camera's positionReplaces Biome effects.sky_color fieldminecraft:visual/cloud_opacityThe opacity of clouds. If 0, clouds are entirely disabled and Happy Ghasts will not regenerate health faster when at cloud height.Value type: float between 0 and 1Default value: 0.0Modifiers: Float ModifiersInterpolated: yesResolved at the camera's position for rendering, or at the position of a Happy Ghast for regenerationminecraft:visual/cloud_heightThe height at which all clouds appear.Value type: floatDefault value: 192.33Modifiers: Float ModifiersInterpolated: yesResolved at the camera's position for rendering, or at the position of a Happy Ghast for regenerationReplaces Dimension Type cloud_height fieldminecraft:visual/default_dripstone_particleThe default particle to be dripped from Dripstone blocks when no fluid is placed above.Value type: Particle OptionsDefault value: {type:"minecraft:dripping_dripstone_water"}Modifiers: overrideInterpolated: noResolved at the position of the Dripstone blockReplaces Dimension Type ultrawarm fieldminecraft:visual/ambient_particlesControls ambient particles that randomly spawn around the camera.Value type: list of objects with fieldsparticle: Particle Options to spawnprobability: float between 0 and 1, the probability to spawn the particle in an empty space when randomly tickedDefault value: []Modifiers: overrideInterpolated: noResolved at the camera's positionReplaces Biome effects.particle fieldminecraft:audio/background_musicControls how and which background music is played.Value type: object with fieldsdefault: optional object with fields:sound: Sound Event to playmin_delay: int, minimum delay in ticks between tracksmax_delay: int, maximum delay in ticks between tracksreplace_current_music: optional boolean, whether this track can replace whatever is currently playingDefault: falseIf not defined and not overridden, no music will start playing while this attribute is activeunderwater: optional object with fields in the same format as default - if present and the player is underwater, will override defaultcreative: optional object with fields in the same format as default - if present and the player is in Creative Mode, will override defaultDefault value: {}Modifiers: overrideInterpolated: noResolved at the camera's positionReplaces Biome effects.music fieldminecraft:audio/music_volumeThe volume at which music should play. Any music playing will fade over time to this value.Value type: float between 0 and 1Default value: 1.0Modifiers: Float ModifiersInterpolated: noResolved at the camera's positionReplaces Biome effects.music_volume fieldminecraft:audio/ambient_soundsControls which ambient sounds are played around the camera, and when.Value type: object with fieldsloop: optional Sound Event, sound to be continually loopedmood: object with fields, sounds that will be randomly played based on surrounding darknesssound: Sound Event to playtick_delay: int, the number of ticks between mood sounds, assuming a light level of 0block_search_extent: int, the radius in which light levels are sampledoffset: double, an additional distance offset to apply to sounds producedadditions: list of objects with fields, sounds that will be randomly playedsound: Sound Event to playtick_chance: float between 0 and 1, probability within a tick to play a given soundDefault value: {}Modifiers: overrideInterpolated: noResolved at the camera's positionReplaces Biome effects.ambient_sound, effects.mood_sound, and effects.additions_sound fieldsminecraft:gameplay/can_start_raidIf false, a Raid cannot be started by a player with Raid Omen.Value type: booleanDefault value: trueModifiers: Boolean ModifiersInterpolated: noResolved at the position that the Raid would be startedReplaces Dimension Type has_raids fieldminecraft:gameplay/water_evaporatesIf true, Water cannot be placed with a Bucket, melting Ice will not produce water, Wet Sponge will dry out when placed, and Dripstone will not produce water from Mud blocks.Value type: booleanDefault value: falseModifiers: Boolean ModifiersInterpolated: noResolved at the position of the interactionReplaces Dimension Type ultrawarm fieldminecraft:gameplay/bed_ruleControls whether a Bed can be used to sleep, and whether it can be used to set a respawn point.Value type: object with fieldscan_sleep: one of:always - the Bed can always be used to sleep (assuming the Bed is not obstructed and there are no monsters nearby)when_dark - the Bed can only be used to be sleep when the global skylight level is less than 4never - the Bed can never be used to sleepcan_set_spawn - same as can_sleepexplodes - optional boolean, if true the Bed will explode when interacted withDefault: falseerror_message: optional Text Component, the message to show if the player is unable to sleep or set their spawnDefault value: {type:"can_sleep_when_dark",error_message:{translate:"block.minecraft.bed.no_sleep"}}Modifiers: overrideInterpolated: noResolved at the head position of the Bed blockReplaces Dimension Type bed_works fieldminecraft:gameplay/respawn_anchor_worksControls whether Respawn Anchors can be used to set spawn (or respawn). If false, the Respawn Anchor will explode once charged.Value type: booleanDefault value: falseModifiers: Boolean ModifiersInterpolated: noResolved at the position of the Respawn Anchor blockReplaces Dimension Type respawn_anchor_works fieldminecraft:gameplay/nether_portal_spawns_piglinControls whether Nether Portal blocks can spawn Piglins.Value type: booleanDefault value: falseModifiers: Boolean ModifiersInterpolated: noResolved at the position of a random Nether Portal blockReplaces Dimension Type natural fieldminecraft:gameplay/fast_lavaControls whether Lava should spread faster and further, as well as have a stronger pushing force on entities when flowing.Value type: booleanDefault value: falseModifiers: Boolean ModifiersInterpolated: noResolved for a whole dimension (cannot be specified on a Biome)Replaces Dimension Type ultrawarm fieldminecraft:gameplay/increased_fire_burnoutControls whether Fire blocks burn out more rapidly than normal.Value type: booleanDefault value: falseModifiers: Boolean ModifiersInterpolated: noResolved at the position of the burning Fire blockReplaces #increased_fire_burnout Biome Tagminecraft:gameplay/piglins_zombifyControls whether Piglins and Hoglins should zombify.Value type: booleanDefault value: trueModifiers: Boolean ModifiersInterpolated: noResolved at the position of the zombifying entityReplaces Dimension Type piglin_safe fieldminecraft:gameplay/snow_golem_meltsControls whether a Snow Golem should be damaged.Value type: booleanDefault value: falseModifiers: Boolean ModifiersInterpolated: noResolved at the position of the Snow GolemReplaces #snow_golem_melts Biome TagDimension TypesAdded new attributes field for dimensions to specify Environment AttributesRefer to the Environment Attributes section for information about the format of this fieldMany fields have been migrated to Environment Attributes:Note: the form of these attributes may not be identical to the original fieldsultrawarm -> minecraft:gameplay/water_evaporates, minecraft:gameplay/fast_lava, visual/default_dripstone_particlebed_works -> minecraft:gameplay/bed_rulerespawn_anchor_works -> minecraft:gameplay/respawn_anchor_workscloud_height -> minecraft:visual/cloud_heightpiglin_safe -> minecraft:gameplay/piglins_zombifyhas_raids -> minecraft:gameplay/can_start_raidnatural (note: not removed) -> minecraft:gameplay/nether_portal_spawns_piglinBiomesAdded new attributes field for biomes to specify Environment AttributesRefer to the Environment Attributes section for information about the format of this fieldNote: certain attributes, such as gameplay/fast_lava are not evaluated positionally and thus cannot be set on a BiomeMany subfields under effects have been migrated to Environment Attributes:Note: the form of these attributes may not be identical to the original fieldsfog_color -> minecraft:visual/fog_colorwater_fog_color -> minecraft:visual/water_fog_colorsky_color -> minecraft:visual/sky_colorparticle -> minecraft:visual/ambient_particlesambient_sound, mood_sound, additions_sound -> minecraft:audio/ambient_soundsmusic -> minecraft:audio/background_musicmusic_volume -> minecraft:audio/music_volumeItem Componentsminecraft:kinetic_weaponAdded new field:contact_cooldown_ticks: integer, the cooldown in ticks after hitting, and loosing contact with an entity before being able to hit it againDefault value: 10Biome TagsRemoved #snow_golem_melts and #increased_fire_burnout - replaced by gameplay/snow_golem_melts and gameplay/increased_fire_burnout Environment AttributesRemoved #plays_underwater_music - replaced by only_underwater field in the audio/background_music Environment AttributeRemoved #has_closer_water_fog - replaced by visual/water_fog_radius Environment AttributeResource Pack Version 70.1SoundsAdded new sound events for the Nautilus:entity.nautilus.ridingFixed bugs in Minecraft snapshot 25w42aMC-263562 - World types in Realms backup info screen are untranslatableMC-298405 - Text components in the "label" of input controls in dialogs don't support "hover_event"MC-299876 - Labels for booleans within dialogs are rendered in a slightly different shade of white than normalMC-301271 - Object text components do not render in some places unless there are text glyphs on the same lineMC-301518 - The mouse cursor doesn’t change to the hand shape when hovering over checkboxesMC-301520 - The mouse cursor doesn’t change to the hand shape when hovering over the difficulty lock buttonMC-301557 - The shading direction of the bolts on single and large copper chests does not matchMC-301879 - Double weathered and waxed weathered copper chests' bottom texture looks off compared to the other variantsMC-302071 - Single and double copper chests have inconsistent side texturesMC-302246 - Sprite object component does not render in server list depending on component treeMC-302409 - Lightning that strikes waxed lightning rods do not deoxidize nearby unwaxed copper blocksMC-302656 - Skeleton horses burn in the sunlightMC-302657 - The "subtitles.entity.nautilus.eat" string misspells the word “Nautilus” as “Nauilus”MC-302664 - Piglins aren't attracted to golden nautilus armorMC-302672 - "Invalid player data" error when loading a world in which you have an effect appliedMC-302680 - Zombie horses and zombie nautiluses cannot be spawned in Peaceful difficultyMC-302683 - The "Confirm Command Execution" dialog is popped up for commands with a permission level of 0MC-302729 - Blast furnaces do not smelt nautilus armorMC-302732 - Performing a charge attack with a spear in your off hand applies the effects from the enchantments present on the item held in the main handMC-302743 - Repeatedly using a spear keeps performing charge attacks every 10 ticksMC-302767 - Holding a spear in Spectator mode and performing a jab attack plays the jab soundMC-302783 - Baby nautiluses use #minecraft:nautilus_taming_items instead of #minecraft:nautilus_food for growing upMC-302802 - Spear charge attack breaks item frames when stillMC-302813 - Zombified piglins no longer appear to sprint or make any angry noises when angryMC-302816 - When running NBT to SNBT conversion, the program waits for 1 minute after completionMC-302817 - Spears with Fire Aspect can ignite victims even when the attacks are blockedMC-302818 - Zombie horsemen can occasionally spawn holding something other than an iron spearMC-302827 - Spears can jab through wallsMC-302834 - Wolves' eyes don't turn red when angryMC-302838 - Extreme TPS lag when using high Lunge levels with UnbreakingMC-302842 - Nautiluses and zombie nautiluses never despawnMC-302920 - "scoreboard players display" settings sometimes reset on world loadMC-302924 - Players can no longer be invited to realmsMC-302984 - Holding a spear in the off hand and attacking an entity adds the spear's attack damage to the attackMC-302988 - Bees no longer get angry at players or mobsMC-303083 - Searching in the resource/data pack selection screens doesn't properly scroll to the resultsMC-303089 - Level 3 operators cannot use client-side operator featuresMinecraft snapshot 25w42a isn't a big snapshot filled with new features for regular players to explore. However, modders will definitely have their eyes on new Environmental Attributes and all the possibilities it brings. Also, not to mention, bug fixes are helping smooth out the new Mounts of Mayhem features as well as old issues with Minecraft Java Edition.