Editing the main settings of the terrain material with M4 has been simplified from what you’re most likely use to with other projects. A lot of the commonly used settings can be found within the MagicMapMaterialBP (M³BP) details panel. This blueprint has been placed in each of the biome maps that came with M4, it visually looks like three circles with the desert, tundra, and island biomes contained within – similar to the image on the right.
If you click on this icon in your world, or “MagicMapMaterialBP” within the World Outliner you will find settings within the details panel which are organized with intuitive names and subcategories. Each of these pertain to different aspects of the Terrain Material. Every parameter/slider within this blueprint is organized in a similar fashion and explained in detail within the Terrain Customization Settings section of the documentation.