Check out a new highly detailed, fully procedural, tileable rock material by Steve Holt which can help you build nature scenes with the help of Substance Player.
Basically, this is an eroded desert sandstone material the artist has been working on for a while. This substance is said to be extremely versatile, allowing users to set up a number of very different looking eroded sandstone cliffs. Check out the gif below to witness the power here.
Please note that you’ll need Substance Player to do custom tweaking, but the pack also features pre-exported TGA textures if you need them.
You can download Substance Player for free here.