Studio's terrain tools let you create realistic landscapes like oceans, mountains, rivers, and canyons. In this tutorial, you'll sculpt a small island in the middle of an open ocean.
Opening the Terrain Tools
The terrain tools can be opened from the Home tab.
Creating an Ocean
Vast areas of open water can be created with the Sea Level tool.
In the Terrain Editor window, click the Edit tab.
Select the Sea Level tool.
In the Size inputs, change the values to 2000, 100, 2000 and click Create.
The blue region will fill with water.
The Sea Level tool is just one way to generate large regions of terrain. See the Generate tool as an alternative to filling vast areas with land or water.
Sculpting an Island
Basic Formation
The Add and Smooth tools can be used to block out terrain formations, before you start fine-tuning details.
Select the Add tool.
When adding terrain, you'll see a grid appear around your mouse pointer. As you click and drag to create terrain, it will align to the grid. To sculpt the island, aim the camera downward so that the grid is aligned with the water surface.
While rotating the camera to different angles, create a rough island mass by layering terrain on top of the water.
Select the Smooth tool.
Drag the brush around the surface of the island to smooth out rough areas.
Smooth 
Original
Painting Terrain
To create a more natural looking island, you can use the Paint tool to form a sandy beach.
Select the Paint tool and click on the Sand material.
Drag the brush around the edges of the island where the land meets the water.
Customizing Appearance
Each terrain material has a default color, but these can be customized to fit a specific theme like an arctic wasteland or desert. You can also enable decorations such as moving grass.
In the Explorer window, select the Terrain object within Workspace.
In the Properties window, expand the MaterialColors branch.
Enter or select a new RGB value for Grass and Sand (or any other materials you used) to change the appearance of the island.
Finally, all terrain of the Grass material can be decorated with animated blades of grass by toggling on Decoration.
