Garro: Legion of One (Warhammer 40,000 Novels: Horus Heresy)
James Swallow has written several fan favourite Warhammer 40,000 series for the Black Library.  In addition to the Blood Angels, he has also written several of the Horus Heresy novels, A Sisters of Battle novel and one of our audio plays.  He has worked for several other genre publishers, but he assures us that we are his favourite