The Last Son of Prospero is the fifty-fifth short story published in the The Horus Heresy series that was not originally part of a main release anthology. The Last Son of Prospero was first published as part of the Black Library's 2016 Advent Calendar, on day number twenty-four, the last day.
The Thousand Sons Sorcerer Revuel Arvida guided his White Scars kinsmen through all the horrors of the Ruinstorm, even though the psychic exertion almost killed him. Now on Terra, he clings to life by the merest thread, his body ravaged by the curse of his Legion -- the insidious flesh-change. The Primarch Jaghatai Khan demands that Arvida be saved, no matter the cost. But even if such a thing were possible, what would remain of his mind and soul?
- The Last Son of Prospero (Short Story) by Chris Wraight