Install BetterNether on your Fabric server

BetterNether is a Fabric mod that overhauls the Nether. Its project page lists new biomes, plants and materials, new monsters such as the Naga, dark dungeons, and big, rare Nether Cities. It has no Forge or NeoForge build, so it needs a Fabric server and goes in the Mods tab.

Checked against BetterNether 9.0.11 on Fabric 1.20.1 and 26.301.2 (beta) on Fabric 26.3, October 2026.

Pick the right build

BetterNether numbers its builds by Minecraft version, and most of them are betas:

• Fabric, Minecraft 1.20.1: 9.0.11, a full release. It needs Fabric API and BCLib 3.0.x.
• Fabric, Minecraft 26.3: 26.301.2, a beta. It needs Fabric Loader 0.19.0 or newer, Fabric API 0.155.0 or newer, BCLib 26.301.x and World Weaver 26.301.x, and it runs on Java 25.
• Other beta builds exist for 26.1, 26.2 and for 1.21.6 to 1.21.8.

The store installs the newest release if there is one, else the newest beta, else the newest alpha. On 1.20.1 that means 9.0.11, and on 26.3 it means the beta, so expect the beta label there. BCLib itself is an alpha on 26.3, because both of its builds for that version are alphas, and World Weaver is a beta. The panel runs 26.x on Java 25 and 1.20.1 on Java 17 and sets that up when you pick the version.

To change loader or version, open JAR Manager under More, choose Fabric under Server software and the version under Minecraft version, then press Apply change. Change your Minecraft version or mod loader has the steps. Switching reinstalls the server and keeps your world, so make a backup in the Backups tab first.

Install it

1. Open Mods under Content and keep the Modrinth chip selected in the source chip row at the top of the tab. The Game version filter starts on your server's version.
2. Search for BetterNether and press Install.
3. A prompt lists what it needs. On 26.3 the title reads "Needs 3 more add-ons": BCLib, World Weaver and Fabric API. On 1.20.1 it reads "Needs 2 more add-ons": BCLib and Fabric API. Press Install all.
4. Restart from the Console tab. The install toast says "Restart the server to load them".

The jar is large, about 23 MB on 1.20.1 and 28 MB on 26.3. Open the Installed view afterwards and look at BetterNether and its libraries. A Failed to load or Needs badge on a row means the last start's log reported a problem with it. On our 1 GiB test plan the 1.20.1 build was killed twice at "Preparing spawn area: 0%" before the server finished starting, so we have not seen a clean start there.

Players need it too

Modrinth lists BetterNether as required on both the client and the server. Each player installs the same BetterNether and library versions for Fabric and your Minecraft version. Join a modded server from your launcher covers the player side, and Fix the mismatched mod channel list error explains the refusal when versions differ.

Settings

On 1.20.1, BetterNether keeps its settings in config/betternether. The mod's code writes four files there: main.json, generator.json, biomes.json and mobs.json. The 26.x builds use a newer configuration system, and the project documents it in its own wiki at modwiki.ambertation.de. Stop the server before you edit a file in the File Manager.

Minecraft generates new chunks as players explore, and a chunk that already exists doesn't pick up new world generation on its own. So Nether terrain that was generated before you added the mod keeps its old biomes, and new biomes show up in Nether chunks nobody has explored yet.

Updating

Open the Installed view. The panel checks for newer builds by itself. If it finds any, a row shows an Update button and the top button reads Update all (N), which asks you to confirm. Press one, then restart. An update never moves to a less stable channel than the installed build, so a beta install is only offered newer betas or releases.

Common problems

• No results for your version: BetterNether has no build for that Minecraft version. Change the version in JAR Manager.
• A "Needs" badge or a startup stop: BCLib, World Weaver or Fabric API is missing. Install it and restart.
• Other crashes: Fix mod and plugin errors on Minecraft covers reading the Console log.