This was a study into using Zbrush to sculpt out different kinds of rock formations and applying as much detail into them as possible with different brushes and alphas.

 

The next step was retopologizing the high poly mesh to create a low poly game ready mesh and then using Xnormals I baked out the required maps including some extra detail about the high poly mesh including the peaks and valleys and the cavity of the high poly to create extra depth for textures.

 

These rocks are rendered in Marmoset toolbag 2.