The book focuses on detailing the varied enemies of the Imperium found within the :
To carry the "Mark of the Xenos" is also a psychological state. Marines who serve in the Deathwatch are forever changed. They see the "true face" of the galaxy—a place teeming with horrors that most citizens of the Imperium cannot even imagine. warhammer+40k+deathwatch+mark+of+the+xenospdf
Since the is technically obsolete, how do you use it today? Here is the community consensus for Casual/Narrative play : The book focuses on detailing the varied enemies