The Shatter Tool is a tool that uses a Voronoi edges noise to shatter or add cracks to the terrain. The brush size and shape can be configured to change the affected area.
The shatter noise can be configured to have a larger scale, conversely making the cracks appear over a wider area. The width affects how big the cracks between the Voronoi edges are. A larger width means that the cracks will be wider. Toggling the active block changes the brush to use the active block rather than making the cracks with which can be used to make cracks with materials rather than removing mass from the world.
The noise can be configured to work in 3D, meaning the cracks will move in all 3 dimensions or several 1D configurations for each of the Cartesian coordinates. This will make the cracks only appear on that axis. It can also be configured with the seed to use different or random seeds.