http://www.debrismaker.aarondabelow.com/v1/

In this tutorial you will learn how to set up a modeling rig on a sphere object, in order to make it look like a stone.

This technique delivers a very believable result and is absolutely non destructive. Once set up, you can easily modify the results, only by changing the mappingoffsets in the first "cellular" displacement map.

This video is only about the modeling rig, a later tutorial will cover the mapping an texturing for the highpoly, as also an approach to make this a game ready asset.

Part#2 https://www.youtube.com/watch?v=cdpiXLEcCqE