
Modrinth · Minecraft mod
Vanilla Fireflies
Datapack that adds ambient fireflies - now they fly not only near bushes.
Quick answer
Which Vanilla Fireflies release matches 1.21.5-pre2 Forge?
Vanilla Fireflies 4.0+mod targets 25w06a, 25w07a, 25w08a with Fabric, Forge, NeoForge. Installation on the client is optional. Installation on the dedicated server is optional. No extra mods listed for this file.
Where it goes
Is Vanilla Fireflies required on the client, server, or both?
Installation on the client is optional. Installation on the dedicated server is optional.
The source marks this as usable on both the client and server.
What else does Vanilla Fireflies 4.0+mod need?
4.0+mod on 1.21.5-pre2 Forge. Every mod below is checked against that same setup.
This file does not list any required mods. Do not add a library just because a different file uses it.
We only count dependency files that match this setup. A file for another loader does not fill the gap.
Before you install it
Add Vanilla Fireflies without breaking your instance.
Built for Vanilla Fireflies 4.0+mod on 1.21.5-pre2 Forge. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use 4.0+mod. It targets 25w06a, 25w07a, 25w08a with Fabric, Forge, NeoForge; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
This file does not list any required mods. Do not add a library just because a different file uses it.
- 03
Put it on the correct side
Installation on the client is optional. Installation on the dedicated server is optional.
- 04
Pick the file you checked
Use the “Get this file” button beside 4.0+mod. It opens that exact file at the source.
About this project
What does Vanilla Fireflies add?

Fireflies can be found in the swamp and mangrove swamp biome at night
Works only serverside
🏞️ Supported Custom Biomes:
- Terralith
- Biomes O' Plenty
- Regions Unexplored
- Terrestria
- William Wythers' Expanded Ecosphere
- Nature's Spirit
📚Fireflies Settings:
- If you want to use pre-made modes use
/function vanilla_fireflies:menu - You can also change the amount of fireflies with
/function vanilla_fireflies:amount {amount:<an actual integer amount of fireflies particles>} - Or you can fine-tune the parameters using
/function vanilla_fireflies:configure {amount:<an actual integer amount of fireflies particles>,speed:<an actual float speed of particles>, delta_x:<how far along the X axis from the player can the particles appear>,delta_z:<how far along the Z axis from the player can the particles appear>, delta_y:<how far along the Y axis from the player can the particles appear>}- Note: Default values are:
- amount: 25 after 1.21.5/60 before 1.21.5
- speed: 0.3
- delta_x: 40
- delta_y: 10
- delta_z: 40
- Note: Default values are:
📂Installing as datapack
- Download and install datapack in the world
- For a new world: You can click the "Data Packs" option when creating a new world and select this datapack
🔧Installing as mod
- Download and put mod in your .minecraft/mods folder
If you have any questions, bugs, suggestions you can create an issue on github or join our discord server
Project description from Modrinth.
Pick your setup
Vanilla Fireflies by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
25w10a
5 loader builds25w09b
5 loader builds25w09a
5 loader builds25w08a
5 loader builds25w07a
5 loader builds25w06a
5 loader builds1.21.6
5 loader builds1.21.5-pre3
4 loader builds1.21.5-pre2
5 loader builds1.21.5-pre1
5 loader builds1.21.5
5 loader builds1.21.4
5 loader buildsShowing the newest 12 of 17 game versions. Older files are in the list below.
Check the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
Vanilla Fireflies versions and loaders
4.0+mod
vanilla-fireflies-4.0.jar
14 Mar 2025
Looking for an older file? The official Modrinth project page is in Resources.