How i started without idea.

Firstly i create some terrain, and place some trees, rocks and grass with flowers.

Then i create controller and script that changing weather randomly, this script adding fog or rain + wind, day or night and sky, something like that.

I realise that grass in unity is slow!

After that i change some graphics, like post effects and ways to render.

Its just how i start this. . .

Now I have a lot of ideas of what to do!

If you have ideas or suggestions please, write in comments.