‘Strange to think that part of humanity held on to such things even after we had gone to the heavens they were meant to represent, don’t you think?’ asked Keeler with a humourless smile. ‘Relics of misguided philosophy, but like all of the things that humanity clung to as it aged, there is more truth in them than most would care to admit. It is crude, a lie of sorts, but to describe what is happening it will serve.’

Mersadie frowned. There was something in Keeler’s words that sent a prickle of ice over her skin. Behind her, the curtains stirred as a gust of wind blew in through the open windows.

‘Euphrati, what’s wrong? You never talked like–’

‘You need to understand, Mersadie.’ Keeler looked up and her eyes were hard, her voice like the falling of an iron blade. ‘You must understand, or all is lost.’ And her hand spun the disc. The symbols of stone and metal blurred as each ring of the disc began to spin at different speeds – blurred, yet somehow Mersadie could still see each symbol as it flicked around.

‘As above, so below. As in the heavens, so on Earth. As in the immaterium, so in the material.’

Mersadie found that she could not look away from the blur of symbols.

‘Horus is coming to take the throne of humanity and slay the Emperor. The forces of the warp ride with him. Never has such power been turned to a single goal. In the material, in the world of flesh, the battle is one of blood and fire, but as that battle rages so another battle is being fought beyond. Just as Terra sits at the centre of the cosmos in the beliefs of dead stargazers and fortune tellers, so the Emperor and Terra sit at the centre of the forces aligning in the immaterium.’

The spinning rings of symbols were slowing now. At her back, Mersadie felt a cold blast of air. She almost turned, but Keeler was speaking again, her voice louder than the rising wind.

‘The Emperor is holding them back by force of will and by art. He is holding them back and they cannot break Him in the realm beyond. So, they have sent their champion, Horus, to do with bloody hand what they cannot do in spirit. If the defences in the physical world can stand, He can keep the forces of the warp at bay. But if they fail…’ The last ring of the disc was slowing. The wind was billowing through the chamber now. A book tumbled off a table, pages flicking over. ‘The defences are strong and Rogal Dorn is ready, but he does not see the whole scope of the battle. This is not a battle of three dimensions or even four. It is a war split between realms, in which the actions taken in one world affect the other, in which acts done with mortal hands can echo beyond.’