Volcanoes, waterfalls, ravines, and much more.

Good manual, it looks quite comprehensive. Perhaps you could add something about object lighting.
It would also be nice if there were screenshots in some sections; it would make it clearer, although it's not essential.

Okay, it's good when the criticism is objective. I agree, I need to add something about point lights, and I'll also add screenshots as soon as I have some free time on my computer. I wrote this manual on my smartphone, then converted it to PDF and uploaded it here. I'll add screenshots to the Technical Support section.