At Mercy Rock, the 135th Phalanx are losing a war against Chaos-touched rebels. Discipline is failing and their line is set to crumble. With the arrival of the Salamanders, hope is rekindled. But a night is approaching when reality is weakened and ghosts walk the world. As his warriors face the traitors, Librarian Pyriel must confront the mystery of Hell Night. A short story from the Legends of the Space Marines anthology.