From the author of The Siege of Castellax comes an exclusive short story that takes you deeper into the events of the novel. As the feral green-skinned orks swarm across the fortress world of Castellax, Iron Warriors Over-Captain Valax and Techmarine Oriax embark upon a dangerous mission that could decide the course of the war. But can the Iron Warriors trust one another, or will they fall to infighting and treachery?