The squads were splitting to join the standard humans. Such was the noise many of the men on the wall had not noticed their arrival, and a ­ripple of surprise went along the line as they appeared at their sides. Messinius was glad to see they seemed more firm when they turned their eyes back outwards.

‘Anzigus,’ he said to the Death Spectre. ‘Hold back, facilitate communication within the company. Maximum signal gain. This interference will only get worse. See if you can get us patched in to wider theatre command. I’ll take a hardline if you can find one.’

‘Yes, captain,’ said Anzigus. He bowed a helm that was bulbous with additional equipment. He already had the access flap of the bulky vox-unit on his arm open. He withdrew, the aerials on his power plant extending. He headed towards a systems nexus on the far wall of the plaza, where soaring buttresses pushed back against the immense weight bearing down upon them.

Messinius watched him go. He knew next to nothing about Anzigus. He spoke little, and when he did, his voice was funereal. His Chapter was mysterious, but the same lack of familiarity held true for many of these warriors, thrown together by miraculous events. Over their years lost wandering in the warp, Messinius had come to see some as friends as well as comrades, others he hardly knew, and none he knew so well as his own Chapter brothers. But they would stand together. They were Space Marines. They had fought by the returned primarch’s side, and in that they shared a bond. They would not stint in their duty now.

Messinius chose a spot on the wall, directing his other veterans to left and right. Kryvesh he sent to the mortal officer’s side. He looked down again, out past the enemy and over the outer palace. Spires stretched away in every direction. Smoke rose from all over the landscape. Some of it was new, the work of the daemon horde, but Terra had been burning for weeks. The Astronomican had failed. The galaxy was split in two. Behind them in the sky turned the great palace gyre, its deep eye marking out the throne room of the Emperor Himself.

‘Sir!’ A member of the Palatine Guard shouted over the din. He pointed downwards, to the left. Messinius followed his wavering finger. Three hundred feet below, daemons were climbing. They came upwards in a triangle tipped by a brute with a double rack of horns. It clambered hand over hand, far faster than should be possible, flying upwards, as if it touched the side of the towering gate only as a concession to reality. A Space Marine with claw locks could not have climbed that fast.

‘Soldiers of the Imperium! The enemy is upon us!’