‘They were inaccurate by a factor of at least thirty per cent,’ cut in Kazzim-Aleph-1, ‘maybe more. We cannot yet be precise, of course, but if the core data is correct, the enemy has brought a force numbering many thousands of vessels from the immaterium.’

‘Thank you for your clarification, magos-emissary,’ said Dorn. Su-Kassen almost flinched at the ice in the words. Kazzim-Aleph-1 seemed oblivious to it.

‘I am charged by the Fabricator General to aid your command in addition to representing the positions of Mars. I am…’ he paused, as cogs turned and buzzed, ‘…pleased that my function is of utility to you, Lord Praetorian.’

Su-Kassen thought she heard Malcador stifle a cough that might have been a laugh. For a giddy moment she found herself almost wanting to smile herself, and then clamped down on the feeling. It was tension and the truth of what was happening finding a way of bleeding out, of breaking the silence. She wondered for a second if somewhere out there, under the blanket drone of alert sirens, there were people laughing as they felt the seconds tick by and future come closer.

It was Sanguinius who broke the silence, walking forwards and raising a hand to dip his fingers into a turning sphere of light.

‘It will be Uranus next,’ he said. ‘And if the attack is not already under way, it will be soon.’

Su-Kassen let out a breath she had not realised she was holding. Around her she felt the command staff relax and refocus. That had been deliberate, she thought. With but a few words the Angel had bent them all in a direction of his choosing.

‘Signal relay to the outer spheres is still clear, lord,’ said Su-Kassen, ‘but there has been no word from Lord Halbract at Uranus yet.’

‘You are still sure this is the path?’ asked the Khan. He had held back, close to the doors and, apart from his glance at Sanguinius, he had remained utterly still. There was something in that stillness that was like the flash of lightning frozen in the eye. ‘There are other ways – Horus could be scattering his might out in the depths beyond, and then circle them in, closing from all sides, strangling us as he cuts us.’

Dorn looked at the Khan.

‘This is Horus. Do you still think he will be anything but himself?’

‘He is not himself,’ said Sanguinius without turning from where the holo-light played over his hand. Su-Kassen felt the tension snap back into place in the room. She felt as though she and the rest of her staff had intruded on a conversation that these demigods had brought with them. ‘You have not seen him, Rogal,’ continued Sanguinius. ‘You have not seen the face of what has taken our brother.’