Minecraft version
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CurseForge · Minecraft mod
old_world.jar
this is a mod that adds some new biomes/blocks
Choose a version Pick your version below, then grab the matching file.
Quick answer
Which old_world.jar release should I use?
Latest stable file oldworld_jar-1.3.0-neoforge-26.1.2.jar
Game version 26.1.2
Loader NeoForge
old_world.jar oldworld_jar-1.3.0-neoforge-26.1.2.jar targets 26.1.2 with NeoForge. The project page does not say whether this file belongs on the client, dedicated server, or both. No extra mods listed for this file.
Where it goes
Is old_world.jar required on the client, server, or both?
The project page does not say whether this file belongs on the client, dedicated server, or both.
Client Source doesn’t say
Dedicated server Source doesn’t say
Loader for this release NeoForge
Required install it here Optional supported, not mandatory Not supported do not install here Source doesn’t say do not assume
The source does not explicitly classify this release as client-only or server-only.
What else does old_world.jar oldworld_jar-1.3.0-neoforge-26.1.2.jar need?
oldworld_jar-1.3.0-neoforge-26.1.2.jar. Change the file and its required mods may change too.
This file does not list any required mods. Do not add a library just because a different file uses it.
This file does not list any required or optional mods.
Before you install it
Add old_world.jar without breaking your instance.
Built for old_world.jar oldworld_jar-1.3.0-neoforge-26.1.2.jar. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use oldworld_jar-1.3.0-neoforge-26.1.2.jar. It targets 26.1.2 with 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
The project page does not say whether this file belongs on the client, dedicated server, or both.
- 04
Pick the file you checked
Use the “Get this file” button beside oldworld_jar-1.3.0-neoforge-26.1.2.jar. It opens that exact file at the source.
About this project
What does old_world.jar add?
this mod adds the toxic land with some new items and adds the thelightworld with some cool mobs
the mod was made with mcreator and blockbench.
the mod has also some easter eggs
and 0.
it adds uranium
a farry
and the aether
it makes the game littel bit better and fun
and you have now a new type of wood
some new things will be added later.
Project description from CurseForge.
Pick your setup
old_world.jar by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
Check the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
old_world.jar versions and loaders
oldworld_jar-1.3.0-neoforge-26.1.2.jar
update-1.3.0-neoforge-26.1.2.jar
10 Oct 2026
Client Source doesn’t say Server Source doesn’t say Dependencies No extras listed Listed on Release listing
Check the 26.1.2 · NeoForge setup NeoForge26.1.2 release
update-1.0.0-neoforge-26.1.2.jar
6 Oct 2026
Client Source doesn’t say Server Source doesn’t say Dependencies No extras listed Listed on Release listing
Check the 26.1.2 · NeoForge setup NeoForge26.1.2 alpha
Looking for an older file? The official CurseForge project page is in Resources.