The companion novel to the Warhammer 40,000 boxed game Assault on Black Reach tells the story of how the 2nd Company of the Ultramarines, commanded by Captain Sicarius, prosecuted war against the greenskin invaders and their warlord Zanzag.

When the planet of Black Reach is invaded by a mighty ork horde, the Ultramarines must act fast. If the orks gain a foothold in the system, they could spread, and threaten the entire sector. As the Ultramarines attack in their righteous fury, the scene is set for a classic battle - one hundred Space Marines versus fifty thousand orks!