A Grey Knights Apothecary is a specialist officer of the Grey Knights Space Marine Chapter who possesses advanced biomedical and scientific training and who serves as a combat medic and research physician for his Chapter. An Apothecary's role in battle is to recover the gene-seed from slain Astartes and to tend to the wounded and maimed.
Grey Knights, The existence of the Chapter is virtually unknown outside of the Inquisition and the highest echelons of the Imperial Adepta, and is a well-guarded secret. Unlike other Astartes, every Grey Knight is a potent psyker. Yet, in the 10,000 standard years of Imperial history, no Grey Knight has ever been corrupted by the Ruinous Powers of Chaos.