Minecraft 25w04a Update - What's New
Added leaf litter decorative block and firefly bush with ambient particle effects. Continued work on 1.22 features.
Overview
Minecraft 25w04a is a weekly development snapshot for Minecraft: Java Edition, published on January 22, 2025. Snapshots are Mojang's weekly previews of in-progress features (development week 4 of 2025), shipped early so the community can test and report problems before anything is finalized. This one logs 4 changes you can try in a throwaway test world.
The work in this update spans blocks & items and gameplay. On the blocks & items side it brings leaf litter and firefly bush.
This build is part of the development cycle leading to a future 1.21.x / 1.22 release. Treat it as a preview rather than a destination: features can change, be renamed, or be cut entirely before they reach the stable release, so it is meant for testing and feedback, not for your main world or a live server.
Changes
#Blocks & Items(3)
- Added leaf litter (thin decorative ground block)
- Added firefly bush (emits firefly particles at night)
- Leaf litter can stack up to 4 layers
#Gameplay(1)
- Firefly bush adds ambient lighting near swamps and forests
Server Admin Migration Guide
- Snapshot only - do not use in production
Known Issues
- Firefly particle effects being tuned for performance
What This Means
For players
Snapshots are opt-in through the official launcher. Always make a copy of any world before opening it in 25w04a, because development builds can corrupt saves and there is no guarantee the world will open in a later version. Use a fresh test world to try the new content safely.
For server admins
Do not run 25w04a on a public server. Snapshots are unsupported by server software and most plugins. Spin up a private staging instance, confirm your plugins load, and report regressions while there is still time to fix them before release.
Background & Context
- Snapshots ship roughly once a week during active development and are enabled through the "Latest snapshot" toggle in the official launcher.
- The content here was being developed toward a future 1.21.x / 1.22 release; individual features may have been adjusted, renamed, or removed before that version shipped.
- Always keep a backup of important worlds before changing versions; the Astroworld versions database tracks client and server compatibility for 25w04a.
Frequently Asked Questions
When was Minecraft 25w04a released?
Minecraft 25w04a was released on January 22, 2025 as a weekly development snapshot for Minecraft: Java Edition.
What is new in 25w04a?
Added leaf litter decorative block and firefly bush with ambient particle effects. Continued work on 1.22 features. Notable entries include: Added leaf litter; Added firefly bush; Leaf litter can stack up to 4 layers. In total it documents 4 changes across 2 categories.
Should I use 25w04a on my main world?
No. 25w04a is a weekly development snapshot meant for testing. Keep your main world on the latest stable release and only open a backup copy in a separate test world to try the new content.
Can I run 25w04a on a Minecraft server?
It is not recommended for a public server. Snapshot only - do not use in production. Use a private staging instance to test plugins and mods, not to host players.
Which Minecraft version is 25w04a a preview of?
25w04a is part of the development cycle for a future 1.21.x / 1.22 release. Features shown here are still in progress and may change before the final release.
Are there known issues in 25w04a?
Yes. Documented issues for this build include: Firefly particle effects being tuned for performance. Development builds are expected to have rough edges that get fixed before release.
Looking for version compatibility info?
Check client and server version details on our versions database.