Complete And Total Terrain Overhaul (CATTO)
by oovaa8
Complete And Total Terrain Overhaul (CATTO) reshapes vanilla terrain into larger, more realistic landscapes, with new biomes and cliffs for players exploring a world on Fabric or NeoForge.
What it does
Generation changes apply to new chunks in the overworld, so terrain grows larger and more varied than in vanilla. Steep sections of the land are reworked, which changes how cliffs and slopes look when a player walks or flies across them. The mod adds Kelp Forests, Brine Pools and Blooming Biosphere to the biome mix, and Create Cosmonautics Deep Seas is one of the other mods the author notes say it can work alongside.
The mod needs C2ME OpenCL Acceleration Module as a required dependency, and the author notes ask that a compatibility patch be loaded after datapacks. Voxy and Distant Horizons are named as ways to see distant terrain without the same load on the computer. A server running it needs every connecting player to have it too. Files exist for 1.21.1 on Fabric and NeoForge, and the code is open source under the Mozilla Public License 2.0.
Key features
Larger terrain
Vanilla landforms are reshaped into bigger, more realistic shapes across the overworld.
New biomes
Kelp Forests, Brine Pools and Blooming Biosphere add underwater and vegetated areas to the generated world.
Reworked cliffs
Steep terrain is generated with changed cliff shapes, so high ground reads more clearly from a distance.
Distant terrain support
The author notes describe rendering far terrain through Voxy and Distant Horizons without melting the computer.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Requirements
Dependencies declared by the latest file for each loader.
Required 1
Use cases
Exploration worlds
Players who want longer journeys between landmarks can start a new world where the terrain covers more ground.
Multiplayer servers
Server owners install the mod on the server and every client, which keeps the generated terrain the same for all players.
Who it’s for: Players and server owners who want a new overworld with larger and more varied landforms, and who can run C2ME OpenCL Acceleration Module alongside it.
How it compares
WorldgenTweaks is a Fabric-only mod for 1.21.8 – 1.21.11 that is server-side only and open source under the GNU General Public License v3.0 or later. Epic Terrain covers Fabric, Forge, NeoForge and Quilt for 1.19 – 1.21.4, is server required with client optional and is open source under the MIT License. CATTO is client and server and targets 1.21.1 only.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Complete And Total Terrain Overhaul (CATTO) | Fabric and NeoForge | 1.21.1 | Client and server | 2026-07-17 |
| WorldgenTweaks | Fabric | 1.21.8 – 1.21.11 | Server-side only | 2025-12-21 |
| Epic Terrain | Fabric, Forge, NeoForge and Quilt | 1.19 – 1.21.4 | Server required, client optional | 2026-06-23 |
Questions
Does Complete And Total Terrain Overhaul need C2ME OpenCL Acceleration Module?
Does the server need the mod if players already have it?
Which loaders are supported?
In the catalog
Complete And Total Terrain Overhaul (CATTO) is one of 8,515 World generation mods on ModsFinder, and one of 4,027 World generation mods for Fabric. 32,366 mods support Minecraft 1.21.1.
Similar mods
What the author says
Report any issues with other mods that the world height causes on github
Official listing
- Modrinth page
- modrinth.com/mod/catto
- Owner
- oovaa8
- Published
- 2026-07-10
- Updated on Modrinth
- 2026-07-17
- Facts verified
- 2026-10-15