There's also some built-in ability to create a custom terrain as of iC5.5.
Scroll down to find "Create Custom Terrain."
http://www.reallusion.com/iclone/iclone_whatsnew_v55.aspx
You quickly run into limitations, which is why they direct you to Earth Sculpture, but it's a start.
iClone 7... Character Creator... Substance Designer/Painter... Blender... Audacity...
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