The Aghoru parted as the Sekhmet approached the crest of the valley, the sharpened blades of their falarica glittering in firelight. Ahriman had no fear of such weapons, but he had no wish to start a fight he didn’t need to.

Ahriman marched towards the Aghoru, keeping his pace steady, and his gaze was lifted upwards in awed amazement as the titanic guardians of the valley were revealed to his sight.

ON PROSPERO, THE cult temple of the Pyrae was a vast pyramid of silvered glass with an eternally burning finial at its peak. Where the other cult temples of Tizca raised golden idols of their cult symbols before their gates, the Pyrae boasted a battle-engine of the Titan legions.

Supplicants to the pyromancers approached along a brazier-lit processional of red marble towards a mighty warlord Titan. Bearing the proud name Canis Vertex, the engine had once walked beneath the banners of Legio Astorum, its carapace emblazoned with a faded black disc haloed by a flaming blue corona.

Its princeps was killed and its moderati crushed when the engine fell during the bloody campaigns of extermination waged in the middle years of the Great Crusade against the barbaric greenskin of the Kamenka Troika. The Emperor had issued the writs of war, commanding the Thousand Sons, Legio Astorum and a Lifehost of PanPac Eugenians to drive that savage race of xenos from the three satellite planets of Kamenka Ulizarna, a world claimed by the Mechanicum of Mars.

Ahriman remembered well the savagery of that war, the slaughter and relentless, grinding attrition that left tens of thousands dead in its wake. Imperial forces had been victorious after two years of fighting and earned a score of honours for the war banners.

Victory had been won, but the cost had been high. Eight hundred and seventy-three warriors of the Thousand Sons had died, forcing Magnus so reduce his Legion from ten fellowships to the Pesedjet, the nine fellowships of antiquity.

Of greater sorrow to Ahriman was the death of Apophis, Captain of the 5th Fellowship and his oldest friend. Only now that Apophis was dead, was Ahriman able to use that word.

Canis Vertexhad been brought down on the killing fields of Coriovallum in the last days of the war by a gargantuan war machine of the greenskin, crudely built in the image of their warlike gods. Defeat seemed inevitable until Magnus stood before the enemy colossus, wielding the power of the aether like an ancient god of war.

Two giants, one mechanical, one a flesh and blood progeny of the Emperor, they had faced each other across the burning ruins, and it seemed the battle’s conclusion could not have been more foregone.

But Magnus raised his arms, his feathered cloak billowed by unseen storms, and the full fury of the aether unmade the enemy war-engine in a hurricane of immaterial fire that tore the flesh of reality asunder and shook the world to its very foundations.

All those who saw the giant primarch that day would take the sight of his battle with that bloated, hateful, war machine to their graves, his power and majesty indelibly etched on their memories like a scar. Ten thousand warriors bowed their heads to their saviour as he returned to them across a field of the dead.

The Legio Astorum contingent had been destroyed, and Khalophis of the 6th Fellowship had “honoured” their sacrifice by transporting Canis Vertexback to Prospero and setting it as a silent guardian to the temple of the Pyrae. The raising of such a colossal sentinel was typical Pyrae showmanship, but there was no doubting the impart made by the sight of the dead engine sheened in the orange firelight of the temple.

Ahriman was no stranger to the impossible scale of the Mechanicum war engines, but he had never seen anything to compare with the guardians of the valley.

TALLER THAN C ANIS Vertex, the identical colossi that stood at the end of the valley were, like the mountain they inhabited, enormous beyond imagining. Soaring, graceful and threatening, they were mighty bipedal constructions that resembled an impossibly slender humanoid form. Crafted from something that resembled porcelain or ceramic the colour of bone, they were manufactured as though moulded from one enormous block.

Their heads were like sinuous helmets studded with glittering gems, and graceful spines flared from their shoulders like angelic wings. These guardians were prepared for war. One arm ended in a mighty fist, the other in an elongated, lance-like weapon, its slim barrel gracefully fluted and hung with faded banners.

“Sweet Mother of the Abyss,” said Phosis T’kar at the sight of them.

Ahriman felt the calm he had established within him crumble when confronted by such powerful icons of war. Like gods of battle, the towering creations rendered everything in the valley inconsequential. He saw the same grace and aesthetic in these guardians as he had seen in the valley’s formation. Whoever had willed this mountain into existence had also crafted these guardians to watch over it.

“What are they?” asked Hathor Maat.

“I don’t know,” said Ahriman.

“Xenos Titans?”

“They have the look of eldar about them,” said Phosis T’kar.

Ahriman agreed. Two decades ago, the Thousand Sons had detected a fleet of eldar vessels on the edge of the Perdus Anomaly. The encounter had been cordial, both forces passing on their way without violence, but Ahriman had never forgotten the elegance of the eldar ships and the ease with which they navigated the stars.

“They must be war engines,” said Hathor Maat. “Khalophis would kill to see this.”

That was certainly true. Khalophis was Pyrae, and a warmongering student of conflict in all its most brutal forms. If an enemy was to be wiped from the battlefield with overwhelming firepower, it was to Khalophis the Thousand Sons turned.

“I’m sure he would,” said Ahriman, dragging his eyes from the titanic war machines. The valley was filled with Aghoru tribesmen, all bearing burning brands or battering their palms bloody on tribal drums.

Phosis T’kar held his bolt pistol at his side, but Ahriman could see his urge to use it was strong. Hathor Maat held his heqa staff at the ready. Warriors who had faced the Dominus Liminus and achieved the rank of adept could release devastating bursts of aetheric energy through their staffs, but here it was no more than a symbol of rank.

“Hold to the Enumerations,” he whispered. “There is to be no killing unless I give the word.”

Perhaps a thousand men and women in hooded robes and reflective masks filled the valley, surrounding a great altar of basalt that stood before a yawning cave mouth set in the cliff between the towering guardians.

Ahriman immediately saw that this cave was no deliberately crafted entrance to the mountain. An earthquake had ripped it open and the blackness of it seemed darker than the depths of space.

“What’s going on here?” demanded Phosis T’kar.

“I do not know,” said Ahriman, advancing cautiously through the Aghoru, seeing the crimson plates of the Sekhmet’s armour reflected in their masks. The chanting ceased and the drumming diminished until the valley was utterly silent.

“Why are they watching?” hissed Hathor Maat. “Why don’t they move?”

“They’re waiting to see what we do,” replied Ahriman.

It was impossible to read the Aghoru behind their masks, but he didn’t think there was any hostile intent. The mirror-masked tribesmen simply watched as Ahriman led the Sekhmet through the crowds towards the basalt altar. Its smooth black surface gleamed in the last of the day’s light, like the still waters of a motionless black pool.

Tokens lay strewn across the altar’s surface, bracelets, earrings, dolls of woven reeds and bead necklaces; the personal effects of scores of people. Ahriman saw footprints in the dust leading from the altar to the black tear in the mountainside. Whoever had made them had gone back and forth many times.