Here are some free custom nodes that can be installed in Substance Designer 2017.
* AddToGround, a node where you can for example add gravel to an already deformed shape.
* Two rock shapes.
* An improved edge detect where you can define the thickness and roundness using masks.
* A first version of my cell shift node. I use this node to randomly shift cells for some variation. Useful when you create rocks out of cells and want to overlap them a little bit.
Skill level: Intermediate