[Mirrored from UPM, not affiliated with Unity Technologies.] 📦 The Terrain Tools package adds additional Terrain sculpting brushes and tools to Unity. This add-on toolset is suitable if you require more control over the appearance of your Terrain, and want to streamline Terrain workflows. It’s also useful when you want to make more complex-looking Terrain, or author Terrain Texture data in external digital content creation tools.
https://docs.unity3d.com/Packages/com.unity.terrain-tools@5.1/manual/index.html