It is a dark time for the Imperial Forces on the isolated planet of HD85512B.
After The initial loss of the major Imperial outposts, Renegade Space Marines have driven the Imperial Guard from their defences and pursued them across the planet.
Evading the dreaded Marines, a ragtag party of survivors led by an unlikely partnership of Commissar-General Marwood and Primaris Azzopardi, have found refuge in the rough mountainous terrain of the Iron Rangers at Cape Sierra.
Little did they know that their prayers to the Holy Emperor for deliverance had been heard as the damaged Frigate Heidelberg limped into Praetorian space with news of the Marine attack.
Fearing that the isolated planet would become a staging base for raids on the Praetorian transit routes to Bakka, Segmentum Command dispatched the 5th Praetorian Battle Column with a modest Navel Patrol Fleet to retake the system…