“The Sanctum awaits the Symbol of Thothmes,” announced Amon, the crimson of his armour seeming to blend with the shadows that gathered around the edges of the pyramid.

Magnus nodded and lifted his golden khopesh from his belt. A flick of his thumb, and the haft extended with a smooth hiss, transforming the sickle-sword into a long-bladed polearm. Magnus rapped the staff on the sun disc, tracing an intricate, twisting shape on the ground.

Ahriman pursed his lips together as the world went dim and the interior of the pyramid was shielded from outside eyes. To be cut off from the aether was unpleasant, but now no one could eavesdrop within the pyramid by any means, be they technological or psychic.

Magnus had once boasted that not even the Emperor himself could penetrate the invisible veil cast around the Rehahti by the Symbol of Thothmes.

“Are we all assembled?” demanded Ahriman, speaking as the Legion’s Chief Librarian. On Prospero, gatherings of the Rehahti would be conducted in aetheric speech, but here the Thousand Sons were forced to rely on the crudity of language.

“I am Ahzek Ahriman of the Corvidae,” he said. “If you would be heard, then speak your true name. Who comes to this Rehahti?”

“I come, Phosis T’kar, Magister Templi of the Raptora.”

“I come, Khalophis, Magister Templi of the Pyrae.”

“I come, Hathor Maat, Magister Templi of the Pavoni.”

“I come, Uthizzar, Magister Templi of the Athanaeans.”

Ahriman nodded as the Captains of the Thousand Sons recited their names. Only Uthizzar hesitated. The young Adept Minor had only recently ascended to the role of Magister Templi, and Ahriman could not look at him without feeling the sorrow of Aphophis’ death.

“We are all assembled,” he said.

“We are alone,” confirmed Amon.

Magnus nodded and looked each of his captains in the eye before speaking.

“I am disappointed in you, my sons,” he said, his voice a rich baritone laden with subtle layers of meaning. These were the first words Ahriman had heard from his primarch since leaving the mountain, and though they were of censure, they were still welcome.

“This world has much to teach us, and you jeopardise that by venturing onto a holy site of the Aghoru. I told you to await my return. Why did you disobey me?”

Ahriman felt the eyes of the captains on him and held himself straighter.

“I ordered it, my lord,” he said. “The decision to march into the valley was mine.”

“I know,” said Magnus, with the barest hint of a smile. “If anyone was going to defy me, it would be you, eh, Ahzek?”

Ahriman nodded, unsure whether he was to be reprimanded or lauded.

“Well, you set foot on the Mountain,” said Magnus. “What did you make of it?”

“My lord?”

“What did you feel?”

“Nothing, my lord,” said Ahriman. “I felt nothing.”

“Exactly,” said Magnus, stepping from the sun disc and following the white spiral out from the centre of the pyramid. “You felt nothing. Now you know how mortals feel, trapped in their silent, dull world, disconnected from their birthright as an evolving race.”

“Birthright?” asked Hathor Maat. “What birthright?”

Magnus rounded on him, his eye transformed into a flickering blue orb, alive with motion.

“The right to explore this brilliant, dazzling galaxy and all its wonders with their eyes open to its glory,” said Magnus. “What is a life lived in the shadows, a life where all the shining wonders of the world are half-glimpsed phantasms?”

Magnus stopped next to Ahriman and placed a hand on his shoulder. The hand was that of a giant, yet he looked up at a face that was only slightly larger than his own, the features sculpted as if from molten metal, the single eye green once more. Ahriman felt the immense, unknowable power of his primarch, understanding that he stood before a living sun, the power of creation and destruction bound within its beauteous form.

Magnus’ body was not so much flesh and blood, but energy and will bound together by the ancient science of the Emperor. Ahriman had studied the substance of the Great Ocean with the aid of some of the Legion’s foremost seers, yet the power that filled his primarch was as alien to him as a starship was to a primitive savage.

“The Aghoru live on a world swept by aetheric winds, yet they remain untouched by its presence,” said Magnus, walking back towards the sun disc at the centre of the pyramid. His khopesh staff spun in his grip, tracing patterns Ahriman recognised as sigils of evocation that would summon a host of Tutelaries if made beyond the inert air of the Sanctum.

“They come to this Mountain every year, this place of pilgrimage, to bring the bodies of their dead to their final rest. They carry them into the holy valley and place them in the mouth of the mountain, and each time they return, the bodies of the previous year are gone, ‘eaten’ by the Mountain. We all feel that the walls that separate this world from the aether are thin here. The essence of the Great Ocean presses in, yet the Aghoru remain unaffected by its presence. Why should that be? I do not know, but when I solve that mystery we will be one step closer to helping our brothers draw closer to the light at the heart of the universe. There is power in that mountain, great power, yet it is somehow contained, and the Aghoru are oblivious to it except as energy that devours the dead. I only hope that Yatiri forgives your trespass into their holy place, for without his peoples’ help we may never unlock the secrets of this world.”

The primarch’s enthusiasm for the task was infectious, and the shame Ahriman felt at jeopardising Magnus’ great work was like a crushing weight upon his shoulders.

“I will make whatever reparations need to be made, my lord,” said Ahriman. “The Sekhmet marched at my order and I will explain that to Yatiri.”

“That will not be necessary,” said Magnus, once again taking his place at the centre of the pyramid. “I have another task for you all.”

“Anything, my lord,” said Phosis T’kar, and the rest joined his affirmation.

Magnus smiled and said, “As always, my sons, you are a delight to me. The Aghoru are not the only ones who can feel that this world is special. The remembrancers we selected to join our expedition, they know it too, even if they do not consciously realise it. You are to make them welcome, befriend them and study them. We have kept them at a distance long enough; it is time for them to see that we have mellowed to their presence. In any case, I believe the Emperor will soon make their presence mandatory and send thousands more out to join the fleets. Before such an edict becomes law, don the mask of friend, of grudging admirer, whatever it takes to gain their confidence. Study the effects of this world on them and record your findings in your grimoires. As we study this world, we must also study its effect on mortals andourselves. Do you understand this task?”

“Yes, my lord,” said Hathor Maat, the words echoed by the rest of the captains until only Ahriman was left to speak.

He felt the primarch’s eyes upon him, and offered a curt bow, saying, “I understand, my lord.”

“Then this Rehahti is over,” said Magnus, rapping his staff on the sun disc. Light streamed out from the centre, bathing the assembled captains in radiance. The Symbol of Thothmes was undone, and Ahriman felt the wellspring of the aether wash through his flesh.

Amon opened the pyramid’s doors, and Ahriman bowed to the primarch. As the captains made their way outside, Magnus said, “Ahzek, a moment if you please.”

Ahriman paused, and then walked to the centre of the pyramid, ready to face his punishment. The primarch sheathed his khopesh, the haft now returned to its original proportions. Magnus looked down at him, and his glittering green eye narrowed as he appraised his Chief Librarian.