Far from the front lines, Space Marines of the Brazen Minotaurs infiltrate an ancient temple-tomb, seeking an artefact sacred to their Chapter... one that could turn the tide of battle in the Imperium’s favour. But they are not the first to enter the tomb – as the Space Marines race to seize their prize, they are watched from the shadows. Are the mysterious Raven Guard there to help the Brazen Minotaurs, or to destroy them?