Complete and Total Terrain Overhaul (CATTO)

Mod that overhauls overworld terrain generation giving it a much larger scale and adding new biomes

Features

Realistic looking erosion
Giant mountains and oceans
Increased terrain height and depth: -320 to 2032
More stone layers
New biomes including:

• Marshes
• Grasslands
• Kelp Forests
• Brine Pools

Images

!A mountain covered with swamps and forests

!Forest valley surrounded by snowy mountains

!Orange colored ocean with hydrothermal vents

Required Mods

While not needed C2ME OpenCl Acceleration will make the terrain not take hours to generate - requires you to start minecraft with java 25

Recommended Mods

• Blooming Biosphere - It's cliff changes make the steep terrain look so much better
• Voxy or Distant Horizons - Makes the terrain visible without melting your computer
• DH/Voxy Seedgen - Generates terrain super fast

Compatibility

This mod includes patches for:

• C2ME OpenCl Acceleration
• Blooming Biosphere - Make sure to load the built in compatibility patch after the datapack
• Create Cosmonautics and Deep Seas

Incompatible with other terrain mods

Report any issues with other mods that the world height causes on github

Erosion

The erosion in this mod is made using Runevision's erosion filter you can find the original here: https://www.shadertoy.com/view/sf23W1
Also check out Runevision's youtube channel: https://www.youtube.com/@runevision and blog post about this technique: https://blog.runevision.com/2026/03/fast-and-gorgeous-erosion-filter.html