The Book of Nightshade is the revered and sacred tome originally authored by the Night Ravens Space Marine Chapter's first Chapter Master - Council Master Haydrian Lorc. Originally, it was written as a chronicle of the earliest days of the Night Ravens' existence, and speaks of the various trials and tribulations it first encountered following their inception. Over time, subsequent Council Masters have added to this tome, adding their own personal experiences, wisdom and insights. Down the millennia of their existence, this tome has come to define the Night Ravens themselves, as the Chapter's character changed profoundly with the onset of their genetic deficiencies which has continued to plague them.