'Commander,' said Sejanus, rising to embrace Horus.

'Damn me, boy, it's good to see you,' said Horus. 'Part of me died when I lost you.'

'I know, sir,' replied Sejanus as they released each other from the crushing embrace. 'I felt your sorrow.'

'You're a sight for sore eyes, my boy,' said Horus, taking a step back to admire his most perfect warrior. 'It gladdens my heart to see you, but how can this be? I watched you die.'

'Yes,' agreed Sejanus. 'You did, but, in truth, my death was a blessing.'

'A blessing? How?'

'It opened my eyes to the truth of the universe and freed me from the shackles of living knowledge. Death is no longer an undiscovered country, my lord, it is one from which this traveller has returned.'

'How is such a thing possible?'

'They sent me back to you,' said Sejanus. 'My spirit was lost in the void, alone and dying, but I have come back to help you.'

Conflicting emotions surged through Horus at the sight of Sejanus. To hear him speak of spirits and voids struck a note of warning, but to see him alive once more, even if it wasn't real, was something to be cherished.

'You say you're here to help me? Then help me to understand this place. Where are we?'

'We don't have much time,' said Sejanus, climbing the slope to the rise that overlooked the plains and forests, and taking a long look around. 'He'll be here soon.'

'That's not the first time I've heard that recently,' said Horus.

'From where else have you heard it?' demanded Sejanus, turning back to face him with a serious expression. Horus was surprised at the vehemence of the question.

'A wolf said it to me,' said Horus. 'I know, I know, it sounds ridiculous, but I swear it really did speak to me.'

'I believe you, sir,' said Sejanus. 'That's why we need to move on.'

Horus sensed evasion, a trait he had never known in Sejanus before now and said, 'You're avoiding my question, Hastur, now tell me where we are.'

'We don't have time, my lord,' urged Sejanus.

'Sejanus,' said Horus, his voice that of the Warmaster. 'Tell me what I want to know.'

'Very well,' said Sejanus, 'but quickly, for your body lies on the brink of death within the walls of the Delphos on Davin.'

'The Delphos? I've never heard of it, and this doesn't look like Davin.'

'The Delphos is a place sacred to the Lodge of the Serpent,' said Sejanus. 'A place of healing. In the ancient tongues of Earth its name means "the womb of the world", where a man may be healed and renewed. Your body lies in the Axis Mundi chamber, but your spirit is no longer tied to your flesh.'

'So we're not really here?' asked Horus. 'This world isn't real?'

'No.'

'Then this is the warp,' said Horus, finally accepting what he had begun to suspect.

'Yes. None of this is real,' said Sejanus, waving his hand around the landscape. 'All this is but fragments of your will and memory that have given shape to the formless energy of the warp.'

Horus suddenly knew where he had seen this land before, remembering the wondrous geophysical relief map of Terra they had found ten kilometres beneath a dead world almost a decade ago. It hadn't been the Terra of their time, but one of an age long past, with green fields, clear seas and clean air.

He looked up into the sky, half expecting to see curious faces looking down on him from above like students studying an ant colony, but the sky was empty, though it was darkening at an unnatural rate. The world around him was changing before his eyes from the Earth that had once existed to the barren wasteland of Terra.

Sejanus followed his gaze and said, 'It's beginning.'

'What is?' asked Horus.

'Your mind and body are dying and this world is beginning to collapse into Chaos. That's why they sent me back, to guide you to the truth that will allow you to return to your body.'

Even as Sejanus spoke, the sky began to waver and he could see hints of the roiling sea of the Immaterium seething behind die clouds.

'You keep saying "they".' said Horus. 'Who are "they" and why are they interested in me?'

'Great intelligences dwell in the warp,' explained Sejanus, casting wary glances at the dissolution of die sky. 'They do not communicate as we do and this is the only way they could reach you.'

'I don't like the sound of this, Hastur,' warned Horus.

'There is no malice in this place. There is power and potential, yes, but no malice, simply the desire to exist. Events in our galaxy are destroying this realm and these powers have chosen you to be their emissary in their dealings with the material world.'

'And what if I don't want to be their emissary?'

'Then you will die,' said Sejanus. 'Only they are powerful enough to save your life now.'

'If they're so powerful, what do they need me for?'

'They are powerful, but they cannot exist in the material universe and must work through emissaries,' replied Sejanus. 'You are a man of strength and ambition and they know there is no other being in the galaxy powerful enough or worthy enough to do what must be done.'

Despite his satisfaction at being so described, Horus did not like what he was hearing. He sensed no deceit in Sejanus, though a warning voice in his head reminded him that the silver-eyed warrior standing before him could not truly be Sejanus.

'They have no interest in the material universe, it is anathema to them, they simply wish to preserve their own realm from destruction,' continued Sejanus as the chemical reek of the world beyond the illusion returned, and a stinking wind arose. 'In return for your aid, they can give you a measure of their power and the means to realise your every ambition.'

Horus saw the lurking world of brazen iron become more substantial as the warp and weft of reality began to buckle beneath his feet. Cracks of dark light shimmered through the splitting earth and Horus could hear the sound of howling wolves drawing near.

'We have to move!' shouted Sejanus as the wolf pack loped from a disintegrating copse of trees. To Horus, it sounded as though their howls desperately called his name.

Sejanus ran back to the river and a shimmering flat oblong of light rose from the boiling water. Horus heard whispers and strange mutterings issuing from beyond it, and a sense of dark premonition seized him as he switched his gaze between this strange light and the wolves.

'I'm not sure about this,' said Horus as the sky shed fat droplets of acid rain.

'Come on, the gateway is our only way out!' cried Sejanus, heading towards the light. 'As a great man once said, "Towering genius disdains the beaten path, it seeks regions hitherto unexplored".'

'You're quoting me back to myself?' said Horus as the wind blew in howling gusts.

'Why not? Your words will be quoted for centuries to come.'

Horus smiled, liking the idea of being quotable, and set off after Sejanus.

'Where does this gate lead?' shouted Horus over the wind and the howling of wolves.

'To the truth,' replied Sejanus.

The crater began to fill as the sun finally set, hundreds of vehicles of all descriptions finally completing their journey from the Imperial deployment zone to this place of pilgrimage. The Davinites watched the arrival of these convoys with a mixture of surprise and confusion, incredulous as each vehicle was abandoned, and its passengers made their way towards the Delphos.

Within the hour, thousands of people had gathered, and more were arriving every minute. Most of these new arrivals milled about in an undirected mass until the Davinites began circulating amongst them, helping to find somewhere that belongings could be set down and arranging shelter as a hard rain began to fall.

Headlights stretched all the way along the forgotten causeway and through the valley to the plains below. As night closed in on Davin, songs in praise of the Warmaster filled the air, and the flickering glow of thousands of candles joined the light of the torches ringing the gold-skinned Delphos.