And the volleys kept coming, rolling over the top of each other like the rising beat of drums. The loyalist ships wheeled as one and turned, thousands of vessels coming together and diving for the inner system.

The engine light of his fleeing enemies gleamed in the eyes of Horus Aximand as the Throne of the Underworld cut through Pluto’s orbit. It was a battle-barge, not the equal of the great Gloriana-class ships, but still a monarch of destruction. Two companies of Sons of Horus stood ready in its holds, a thousand of the Legion’s best killers, and it mounted cannons that could hammer targets to ruin. The spear-tip force it led had been aimed at Kerberos, a primary strike to take the fortress-moon’s main batteries. That blow would now be left to others. The newborn and the IV Legion could take their objectives and bear the cost. And there would be a cost. Even with the cover of their fleet gone, the fortress-moons were still ship-killers. Tens of thousands would die to take them. That did not matter. All that mattered was that this gate to the Solar System was in their hands.

Aximand could see each of the next moves he had to make, all the gradations of victory and how to reach them. It was as simple as breathing. He understood it in his mind, but also with his soul. That was what had seen him rise in the Legion – his sheer tactical genius. There had been others who were better at the point and edge of killing – though they were few – but Aximand was able to measure war, and to weigh possibility, and then make decisions that won battles. He was ‘Little Horus’ because his face had resembled that of the primarch, but the deeper resemblance lay here, in his ease in the crucible of war. The face that had given him his half-mocking title had been flayed away, but the commander’s soul beneath remained. Seeing the battle sphere of Pluto change, he already knew why and what to do.

‘Battlefleets Ullanor and Shardspear, engage the fleeing enemy ships. Run them down. Fourth Legion battle groups, divert and begin assault on Kerberos, Charon and Hydra.’

Beside Aximand, Vull Bronn sucked in a breath to speak. The veteran warsmith had survived the Iron Warriors’ withdrawal from Krade, but a strike on the last transport had left him with a bloody cave in his side.

‘They are not breaking,’ he rasped. Compression pistons in his rebuilt torso hissed and released. ‘The key values of their force and strength have not fallen to collapse. We should hold to our current deployment.’

‘No,’ said Aximand. ‘They are withdrawing. This is a battle they knew they would lose. They held for as long as they could, slowed us and bled us as much as they could, and now they will run to Terra.’