You get a lot of materials when you purchase True Terrain, especially on Ultimate.
However, I have found, that in order to create more contrast in my scenes, I depend on additional materials. Here I´m presenting you with 40 True Terrain-ready materials, to provide you with additional contrast and variety in your scenes (can one ever have too many materials? ;) )
All materials have been either made entirely by myself or are based on CC0 maps. All maps have been properly renamed and I have created EXR Heightmaps for each of them. Just install via your True Terrain Add-on (Preferences - Install materials & assets) and have fun creating stunning landscape art!