The warriors picked their way over the rubble. A mix of religious buildings, departmento offices and commercial premises delineated the square. The majority were reduced to shells. Signs of deliberate destruction were everywhere. Most buildings had carried the Imperial ‘I’ or the aquila. All these emblems had been torn free or chiselled away, the gougings daubed over with unholy symbols in blood or filth.

The square was impressively sized, but cluttered with the debris of war it looked small and sad. Mouldering bodies impaled on stakes were mounted in groups of three and seven, shrinking the scale of the space with the unwelcome intimacies of torment.

Ranks of saints stood in niches on the cathedral’s double frontage. All of them were headless and their hands hacked off. Beneath the ruined gallery of statues there were three gates, their wood slimy with decay and their metal fittings corroded.

Felix slowed. He held up his hand. The Space Marines readied their weapons.

A second later, a rocket streaked down from the intact tower, blasting a Space Marine to pieces. A Primaris Intercessor raised his bolt rifle and fired. His aim was true, and the broken meat remains of a mortal tumbled from on high, landing with a bloody splash on the paving.

‘Ware!’ shouted Felix.

The Space Marines immediately dispersed, finding cover and bringing their weapons to readiness.

The three gates swung wide. From within the desecrated cathedral stormed a screaming mob of mortal humans. They were as diseased and pathetic as their fellow citizens, but their faces were suffused with a hysterical joy and they capered feebly as they ran at the Space Marines. They had few weapons, looted lasguns mostly. The few that could shoot straight must have been disappointed that their shots did not penetrate power armour.

The Space Marines returned fire. Ten seconds of fully automatic bolter fire was all it took to sweep the area clear.

Felix surveyed the resultant carnage. The humans had been blown apart into scraps of meat and cloth. He felt no emotion at their end. They had made their choice. He set his vox channel to central command.

‘This is Tetrarch Decimus Felix,’ he voxed. ‘Inform the primarch the Cathedral Square is clear. We shall hold as ordered.’

Felix arrayed his men around the cathedral perimeter. They waited. The clouds began to split further, allowing the sun to shine through in its fullness. The day grew muggy, and the thick smell of putrefaction grew worse.

Guilliman arrived half an hour later, escorted by his Victrix Guard, the Adeptus Custodes and ten Sisters of Silence. Codicier Maxim and Lexicanium Gerrundium were among a host of Space Marine psykers that followed, led by Chief Librarian Tigurius of the Ultramarines, summoned back from the southern marches to Espandor. In Guilliman’s shadow, they seemed small as pages dressed whimsically as adult warriors to honour a visiting feudal lord.