Better Underground Caves

Name: Better Underground Caves
Author: wonderful_Ai_Chen

Better Underground Caves changes how large caves and deep underground terrain generate in the world, and it is published for Fabric, Forge, NeoForge and Quilt.

FabricForgeNeoForgeQuiltServer required, client optionalAll rights reserved1.19.2 – 1.21.11

What it does

The mod reworks the original cave terrain and adds large underground cave features. Caves are tuned to reduce vertical drops and to favor flatter ground, so passages tend to run level rather than plunge. Large caves are made less frequent at low elevations, where mountains are the main terrain, and layered structures similar to dungeons are added. Below y 0, randomly generated underground caverns can contain magma rivers.

Better Underground Caves runs on the server, and clients may also install it. Only the server needs it to generate the new caves, and players can join a server that runs it without installing anything. The mod is also distributed as a data pack, so it can be used without a loader. Files are published for 22 release versions, 1.19.2 – 1.21.11, and the latest file is v0.2+mod for 1.21.11, dated 2026-03-03, on the beta channel. The mod is released under All rights reserved and is not open source.

Key features

Reworked cave terrain
The original cave terrain is optimized, with caves shaped to lower the number of steep vertical drops.
Large underground caves
Large cave features are added below the surface, giving bigger open spaces to explore.
Layered dungeon-like structures
Caves are built in layers, similar to the way dungeons are organized.
Magma rivers below y 0
Randomly generated caverns below y 0 can contain rivers of magma.

Gallery

Compatibility

Latest build for each game version and loader.

No stable releases

Every published file is a beta or alpha build.

Version

1.21.x12 of 12 versions with builds

1.21.11v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.10v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.9v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.8v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.7v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.6v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.5v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.4v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.3v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.2v0.2+modv0.2+modv0.2+modv0.2+mod

1.21.1v0.2+modv0.2+modv0.2+modv0.2+mod

1.21v0.2+modv0.2+modv0.2+modv0.2+mod

1.20.x7 of 7 versions with builds

1.19.x3 of 3 versions with builds

ReleaseBetaAlphaNot available

Only full game releases are shown. This mod publishes no snapshot builds.

Use cases

Who it’s for: Players who want larger and flatter underground caves, and server owners who want the new generation in a world without asking players to install anything.

How it compares

Full comparison

Better Lush Caves is licensed under the Apache License 2.0 and is open source; it is server-side required and client optional, and its files cover 1.19 – 1.21.4. Lush Cave Ruins is All rights reserved and not open source, with files for 1.18 – 26.3 and the same server-side environment. Better Underground Caves targets a different cave layout rather than lush biomes, and its files cover 1.19.2 – 1.21.11.

Mod	Loaders	Game versions	Environment	Updated
Better Underground Caves	Fabric, Forge, NeoForge and Quilt	1.19.2 – 1.21.11	Server required, client optional	2026-03-03
Better Lush Caves	Fabric, Forge, NeoForge and Quilt	1.19 – 1.21.4	Server required, client optional	2025-03-17
Lush Cave Ruins	Fabric, Forge, NeoForge and Quilt	1.18 – 26.3	Server required, client optional	2026-09-20

Questions

Does Better Underground Caves need to be installed on the client?

No. The server must run it, while players may leave it out.

Which loaders does Better Underground Caves support?

Files are published for Fabric, Forge, NeoForge and Quilt, and a data pack version is also available.

Can the mod be added to an existing world?

Generation applies to newly generated chunks, so caves in areas already generated will not change. The Modrinth page does not state how existing terrain is handled beyond that.

In the catalog

Better Underground Caves is one of 8,515 World generation mods on ModsFinder, and one of 4,027 World generation mods for Fabric. 19,862 mods support Minecraft 1.21.11.