On the sixth day, an impromptu parade was held through Occullum Square where the crowd threw off its clothes and cavorted naked in the rain. Tizca had no standing force of enforcers, so elements of the Prospero Spireguard were deployed to return the deliriously naked dancers to their abodes. The seventh day saw several members of the parade fall ill with a deadly form of viral pneumonia, and the following morning riots broke out in front of the Pyramid of Apothecaries as frightened people demanded a vaccine. Sixty-three people died before the Spireguard restored order, and a sullen mood fell upon the city.

On the ninth day, the rains finally ceased, and the sun broke through the dark clouds that hung like disapproving judges over the heart of the city. A luminous beam of light shone down on Tizca, bathing it in golden radiance and striking the flaming urn atop the great column at the centre of Occullum Square.

Mahavastu Kallimakus wrote that it was like the light of heaven returning to Prospero.

DEEP WITHIN THE Reflecting Caves, that light retuned to its source.

Magnus opened his eye, and the athame withdrew from his flesh, its blade crumbling to dust as soon as it came into contact with the air. Ahriman let out a relieved sigh as Magnus sat up, swinging his legs over the side of the white slab and blinking furiously in the darkness.

Only the dim glow that swam in the walls illuminated the chamber. Of the thousand Thralls, only eighteen remained alive, though their bodies were gaunt and drained, the glow from their crystals faint and almost extinguished.

“My lord,” said Amon, coming forward with a goblet of water. “It is good to see you.”

Magnus nodded, and Ahriman saw how pale his skin had become. His long red hair was matted with sweat, and Ahriman thought he could see the writhing veins and pulsing organs beneath the primarch’s skin. That was a lie, for Ahriman had seen into the heart of Magnus, and there was nothing so mundane as liver, lungs or kidney within that immortal frame.

Phael Toron, Uthizzar and Auramagma crowded in, their joy at seeing Magnus returned beyond measure. Only Ahriman held back, his emotions mixed at what they had done. For nine long days they had stood vigil over their beloved primarch, neither eating nor sleeping nor partaking of food or water. No words had passed between them, and no communication had been attempted with their brothers on the surface.

“Was it worth it?” asked Ahriman. “Did you succeed?”

Magnus fixed him with his single eye, a dull orb of watery blue, and shook his head slowly.

“No, Ahzek, I think that I did not,” said Magnus. “Just as I attempted to save my brother from the abyss, others were ready to push him in.”

“Others?” snarled Auramagma. “Who?”

“A wretch named Erebus who serves my erstwhile brother, Lorgar, It seems the powers that seek to ensnare Horus Lupercal have already claimed some pieces on this board. The Word Bearers are already in thrall to Chaos.”

“Lorgar’s Legion have betrayed us also?” asked Phael Toron. “This treachery runs deeper than we could ever have imagined.”

“Chaos?” said Ahriman. “You use the term as if it were a name.”

“It is, my son,” said Magnus. “It is the Primordial Annihilator that has hidden in the blackest depths of the Great Ocean since the dawn of time, but which now moves with infinite patience to the surface. It is the enemy against which all must unite or the human race will be destroyed. The coming war is its means of achieving the end of all things.”

“Primordial Annihilator? I have never heard of such a thing,” said Ahriman.

“Nor had I until I faced Horus and Erebus,” said Magnus, and Ahriman was shocked to see the barest flicker in his primarch’s aura.

Magnus was lying to them. He hadknown of this Primordial Annihilator.

“So what do we do now?” asked Uthizzar. “Surely now we must warn the Emperor?”

Magnus hesitated before nodding slowly.

“Yes, we must,” he said. “If my father is forewarned, he can take arms against Horus before it is too late.”

“Why will he believe us?” asked Ahriman. “We have no proof.”

“I have the proof now,” sighed Magnus wearily. “Now return to your cult temples and await my summons. Amon, attend upon me; the rest of you may leave.”

The Captains of Fellowship turned and made their way towards the crystal steps that led out of the cave.

“Ahriman,” said Magnus, “bend all the power of the Corvidae to unravelling the strands of the future. We mustknow more of what is to come. Do you understand me?”

“I do, my lord,” replied Ahriman.

“Do whatever it takes,” said Magnus. “Whatever the cost may be.”

LEMUEL AWOKE TO find Ahriman standing over him. His mentor had a stern look in his eye, and Lemuel immediately felt the tension in the room. He stifled a yawn, realising he’d fallen asleep next to Kallista’s bed once again. Her eyes were closed, though it was hard to tell whether it was in sleep or unconsciousness. Camille sat across from him, her breathing still that of a sleeper.

Camille had recovered well from her ordeal with the psychneuein eggs, quickly returning to her normal, vivacious self.

“My lord?” he said. “What is it?”

Amon and Ankhu Anen stood behind Ahriman, making the room feel suddenly small. “You should leave, both of you,” Ahriman told him. “Leave? Why?”

“Because you will find what has to happen here unpleasant.”

“I don’t understand,” he said, rising from his chair and moving protectively towards Kallista. Camille woke and looked up, startled, as she saw Astartes filling the room.

“Lem?” she asked, immediately picking up on the tension. “What’s going on?”

“I don’t know yet,” he said.

“I do not expect you to understand,” said Ahriman with real regret in his voice. “But events are in motion that require us to know of the future. Our normal methods of gathering such information are denied to us, so we must seek other avenues.”

“What are you going to do? I won’t let you hurt her.”

“I am sorry, Lemuel,” said Ahriman. “We have no choice. This hasto happen. Believe me, I wish it did not.”

Amon moved towards the bank of walnut-panelled machines and turned all the dials to the their middle positions. The light began to fade from the crackling, buzzing globes and the needles on the brass readouts nosed their way down.

“WHAT IS HE doing?” Camille wanted to know. “Lord Ahriman, please?”

Ahriman said nothing, his face betraying his unease.

“You wanted to know what this machine was for?” said Ankhu Anen, taking Lemuel’s arm. The giant Astartes easily pulled him away from Kallista’s side and handed him off to Ahriman. “It is an aetheric blocker. It isolates the subject’s mind from the Great Ocean. We used such devices to subdue our brothers when the flesh change came upon them. It was the only way to stop it. Your friend’s mind is locked open to its roaring tides, and, but for these devices, aetheric energy would be pouring into her.”

“Can you… shut her mind to it?” asked Camille, standing protectively beside her friend.

The Astartes said nothing, and Lemuel read the truth in their auras.

“They can,” he said, “but they won’t.”

“She should be dead already,” hissed Ankhu Anen, dragging Camille out of the way. “She has a unique link to future currents, and we must make use of all the tools available to us.”

“Tools? Is that all we’ve been to you?” asked Lemuel, struggling uselessly in Ahriman’s grip. “All this time, were you just using us?”

“It was not like that,” said Ahriman, casting a poisonous glance at Ankhu Anen.

“Yes it was,” said Lemuel. “I see that now. You think you’re so clever, but you’re blinded by your belief in the superiority of your knowledge. You can’t even contemplate that someone else might know better than you.”