The Carve brush is a special tool that adds a relief effect to the parts of the texture, where the brush shape is drawn. The heightmap profile of the emboss effect is defined by the brush shape itself.

Use the Brush panel to load the brush shape and to define Size, Hardness, Step-Size and Distraction of the brush. Enable the Spray switch to draw without having to move the mouse.

The Amplify Value controls the depth of the relief effect. Set it to a negative value to invert the effect.
Set the Brightness Mode to Normal to have the carved parts be darkened. The deeper the carving is performed, the darker the areas will get. Disable the darkening effect by setting the mode to Bright.