Released back in 2012 as part of Black Library’s 15th birthday celebration, Rob Sanders’ Army of One was one of the first (perhaps actually the first) Horus Heresy short stories to be released as a standalone ebook. Very much a ‘quick read’, it takes a whistlestop tour of one man’s history as he relives the unexpected way in which he was caught up in the Heresy. Unwanted by the Imperial Army, he finds his place in the war in a less obvious role.