Learn more about the Terrain Tools package here in this blog post: https://ole.unity.com/TerrainToolsPackage
This is the Asset Pack we used for the sky in this video: https://ole.unity.com/TimeOfDay
The Terrain Tools package contains brand new sculpting tools and a collection of common-use utilities to help automate tedious tasks.
Existing terrain sculpting tools have been improved with new controls for rotation, spacing and scatter. Strength, size and rotation parameters now have a jitter control to help you add natural variation to your brush strokes. We’ve also added shortcut keys to streamline the terrain brush workflow, providing quick access to common brush controls without needing to fiddle with the Inspector window.
Several new sculpting tools are available when using this package including bridge, clone, noise, terrace, and twist. There are also Erosion tools that modify your height map based on Hydraulic, Wind and Thermal erosion.
The last major addition included in this package is the Terrain Toolbox. Unity 2018.3 enabled users to paint across multiple terrain tiles. This new feature was awesome but needed some important tooling to help streamline the creation of large terrains requiring many tiles and manage existing scenes with multiple terrain tiles.