Kor'sarro Khan: Huntmaster is a short story by Graeme Lyon. It was published online in December 2013 as part of the Black Library Advent Calendar (2013).
On Gehöft, the White Scars battle the forces of Chaos, both mortal and daemonic. As plague spreads and darkness reigns, Kor'sarro Khan takes to the field, eager to take the head of the traitor responsible for the world's corruption. But when his Dark Angels allies abandon the fight, the Khan and his bikers are forced into a deadly confrontation.