As the ork menace ravages the galaxy, the Imperium faces its darkest hour. Its fleets are in ruins, its armies devastated - amongst them the noble Imperial Fists - and even a primarch of myth has fallen against the Beast. As brute force fails, Koorland resorts to increasingly desperate tactics against the greenskins. A final hope lies in deploying the controversial Deathwatch and the Sisters of Silence in a deft strike at the heart of the ork empire.

The Imperium has been brought to the edge of extinction by an ork invasion of unprecedented scale and depth. Piecemeal strikes against the invaders prove ineffective - for every ork fleet destroyed, five more appear. The only solution is to find and kill the orks' warlord - the Great Beast. Surely if its leader is killed, the greenskins' empire will fall apart in agony of infighting and confusion.

The Imperium's attempts to defeat the ork menace seem doomed to failure; it is only a matter of time before the greenskins triumph, and mankind is wiped from the galaxy. Yet there is some cause for hope - the psychic weakness of the orks has been found, and a few Sisters of Silence survive. Supported by the full might and technology of the Adeptus Mechanicus, the Space Marines head to the orks' home world one final time. This time there will be no retreat, no surrender. They must succeed...or die in the attempt.

Tearing itself apart from within, the Imperium is still virtually powerless to resist the ork advance. When the Adeptus Mechanicus reveal they have discovered the orks' point of origin, the Adeptus Astartes start to gather their forces for a massive assault on their enemy's home world. But what the Imperial forces need is a figurehead, a hero from legend to lead them - a primarch.

Across the length and breadth of the galaxy, humankind celebrates its salvation and relishes the prospect of a return to peace. But the war against the orks has driven the political bedrock of the Imperium, exposing its rotten core. One man, one powerful man, decides he has the solution and launches a campaign of destruction so terrible that thousands of years later his actions will still be viewed with horror.

The Imperium's situation has never been more grim - an ork attack moon hangs over Terra, and ork armadas ravage human space. To make matters even worse, eldar strike at the heart of the Imperial Palace, forcing humanity's defenders to fight on two fronts at once. Though it seems nothing can stop the orks - neither brute force, science, nor faith - an unlikely alliance in the furthest reaches of space uncovers the first clue how to defeat the greenskins. The Adeptus Astartes now face an almost impossible task....

Despite the Imperium's best attempts to forestall the ork plague that is wreaking havoc in human space, an ork attack moon now hangs over Terra. As its malevolent presence gazes down at the Imperial Palace, terrified citizens run riot in the streets. In a last-ditch attempt to destroy the attack moon, a proletarian crusade is launched. Thousands of ships large and small head to the moon carrying billions of citizens, all eager to take the fight to the enemy.

As ork ships lay waste to world after world, heading inexorably towards Terra, Imperial citizens despair. The High Lords become desperate to prove that victory is possible, no matter the cost. A massive navy fleet is assembled - their mission to make a definitive strike against the orks at Port Sanctus, an area of enemy-held space. But when the Imperial armada arrives, they find themselves outclassed and outmanoeuvred. Can human courage and faith possibly prevail against such terrible odds?

After centuries of peace, the Imperium is thrown into panic as human worlds everywhere are menaced by orks. In a relentless tide of slaughter, ork attack moons destroy planet after planet with gravity weapons of unstoppable power. On Terra, the High Lords are paralysed by the scale of the threat and fail to take any effective action. With entire Space Marine Chapters missing or known to have been wiped out, does anyone have the will and the power to rise to the Imperium's defence?

It is the 32nd millennium, and the Imperium is at peace. The Traitor Legions of Chaos are but a distant memory, and the many alien races that have long plagued mankind are held in check by the Space Marines. When a mission to exterminate one such xenos breed on the world of Ardamantua draws in more of their forces, the Imperial Fists abandon the walls of Terra for the first time in more than a thousand years.

Belisarius Cawl, Archmagos Dominus of the Adeptus Mechanicus, is the most brilliant mind alive. For 10,000 years he has furthered the cause of mankind, working under the aegis of the Emperor and Lord Commander Roboute Guilliman to prevent the inexorable march of the alien and the traitor. Many call him heretic, but all must recognise the magnitude of his achievements, for who else but he was entrusted to create a new generation of Space Marines?  

On the 13th day of Secundus, the bombardment of Terra began. With the solar defences overcome through the devastating strength of the Traitor armada and the power of the warp, Horus launches his assault on the Throneworld in earnest. After withstanding a ferocious barrage of ordnance, an immense ground war commences outside the Palace, with every inch gained paid for in the lives of billions. 

The shrine world of Divinatus Prime has become lost to the light of the Astronomican, and no ship can piece its veil. Only the Lord of Death himself, Blood Angels Chief Librarian Mephiston, has any hope of discerning the fate of this once pious world. After enacting a powerful blood ritual, Mephiston and an honour guard of his fellow Blood Angels reach the stricken shrine world to find it seized by religious civil war. Each faction fights for dominance of a potent artefact, the Blade Petrific, said to be wrought by the Emperor Himself.  

The hunters have become the hunted. The Night Lords flee to the dark fringes of the Imperium to escape their relentless pursuers - the aeldari of Craftworld Ulthwé. Their flight takes them to the carrion world of Tsagualsa, where their primarch died and their Legion was broken. There, history will repeat itself as a deadly assassin stalks the shadows, and the Night Lords are drawn into a battle they are destined to lose. 

Sent to avenge the deaths of his brothers and purge a dangerous cult, Imperial Fists Primaris Librarian Aster Lydorran finds a foe beyond imagining on Ghyre. Lydorran must use all his strength, will and psychic might to defeat his hidden enemies and avert catastrophe.