An Architect of Fate novella. Chaos Space Marines of the Iron Warriors Legion launch a devastating attack upon their hated foes the Imperial Fists, crippling one of their principal starforts. Unperturbed, the heroic Captain Darnath Lysander withdraws his warriors to a second stronghold, the Endeavour of Will, to weather the rest of the assault. But as the Iron Warriors’ methods are revealed, critical and desperate decisions must be made, lest their insidious techno-contagion spread throughout the Imperial Fists’ fleet and beyond…