In Unity, the best tool to use to create a natural landscape is the terrain tool. Unity's terrain system allows us to sculpt and shape the landscape of our level. This tool is frequently used to create outdoor environments, because the ground is never completely flat in nature. This tool will help the artist create organic and asymmetrical details as well as a realistic ground plane for your player to walk on. After the Terrain is sculpted and formed, we can complete our environment by adding in bushes, trees, and fading materials.
To see how easy it is to use the tool, let's get started with creating the Terrain:
First, let's create a new scene from scratch by going to File | New Scene.
Next, we need to actually create the Terrain we'll be placing for the world. Let's first create a Terrain by selecting GameObject | 3D Object | Terrain.
At this point, you should see the Terrain.