Death Motes

I have a task for you, Maw Walker. Souls deemed suitable for service among the Mawsworn are broken down to their barest essence. The resulting creature forms a black shade, devoid of all individual will. It is a tragic end. I wish to better understand this process--what is it about a soul that causes this transformation? Fragments of broken souls rain down across Ruin's Cradle. Bring me some of them, so that I might learn more about our common adversaries.