The Shadow Crusade has begun. While the Ultramarines are stunned by Kor Phaeron's surprise attack on Calth, Lorgar and the rest of the Word Bearers strike deep into Ultramar. Their unlikely allies, Angron and the World Eaters, continue to ravage every system they come across. On the garrison planet Armatura, this constant ferocity may ultimately prove to be their undoing. Worlds will burn, Legions will collide, and the Primarch will fall.