Soft announced in the tie in fluff for the Crusades supplement, the Norn Emissary (and Norn Assimilator) have finally been revealed.
With the skies darkened, day and night had no meaning. The defenders fought on doggedly, yet their casualties mounted and the fortress they manned became ever more heavily damaged. All the while, the three Norn Emissaries stalked through the fighting with eerie alien grace, closing inexorably upon objectives only they knew. One of them struck on the eighth day of the siege, having compressed its mass into the seemingly impossible confines of a decommissioned turbolift shaft then crawled steadily upwards for untold hours. The towering monstrosity burst into the Erythrad Peak command sanctum, where it slaughtered hundreds of screaming strategos and command adepts and destroyed scoroes of irreplacable cogitator banks. The beast would have escaped to strike again elsewhere, had it not been for an unnamed Chapter serf who selflessy sealed the blood-drenched sanctum and trigged the plasmic denial charges, reducing the entire peak to a glassy crater.
The second Emissary - whose distinctive scars identified it to Imperial strategos as the infamous Fiend of Hag Rift - surged from a Trygon tunnel to attack the White Templars' gene-seed vault. It was supported by swarms of lesser warrior organisms and a pair of Neurotyrants. In response, marching from the Chapter's Vaults of Repose came almost a score of White Templars Dreadnoughts who held back the Tyranids in an increasingly desperate and one-sided struggle. Almost all of the ancient warriors were slain - a dreadful loss for the Chapter - but their sacrifices bought time for Colonel Uveda of the Ortegan Grenadiers to launch a massive counter attack and drive the Tyranids back. When the vengeful Chapter Master Stavro arrived at the head of a White Templars strike force, the Fiend of Hag Rift was badly wounded and its swarm devestated. Yet the malevolent monster escaped to fight another day.
For all the butchery and horror wrought by its fellows, it was the third of the Norn Emissaries that struck at the most crucial target. Scaling the snow-whipped peak of the tallest mountains in the Heights of Artorus, the creature lurked in wait amidst rock and ice for its prey to emege. Below lay the wide-open square of the Ascendorum, a great plaza wrought from a mountainous plateau, dotted with braziers, statuary, sheild generatorums and flak batteries. In better times, the White Templars had mustered on this open space to perform rituals and bestow honours beneath the starry vaults of Sanctum's skies. Now, Lord Solar Leontus was crossing the open plaza astride Konstantin with his entourage about him. The Norn Emissary knew its prey's psionic spoor. Its black eyes followed him. Its ropes of muscle and tendon tensed, and then it leapt out into thin air. The Norn Emissary dropped towards the plaza, sword-like talons extended, angling its huge mass to slam down directly atop Leontus. From below came screams as someone spotted the danger and many amongst Leontus' entourage raised weapons. The Lord himself looked up, registering his doom descending upon him too swiftly to be avoided.
Missiles streaked in and struck the Norn Emissary in the flank when it was scant feet above Leontus' head. The impacts blossomed into concussive fireballs. Their force hurled the huge Tyranid aside even as their shock waves unhorsed the Lord Solar and threw him and many of his companions flat upon the flagstones. The Norn Emissary bucked in the air, ichor gouting from its wounded flank, and turned its tumble into a cat-like landing with a grace nothing so huge should posses. It hissed as the gilded gunship that had fired upon it streaked overhead, then banked sharply with a flare of engines and came in for another pass. The craft's rear ramp whined open as it flew closer, and hulking warriors clad in ornate auramite armour dropped from it one after another to slam down in the plaza with enough force to crack stone. The gunship's weapons blazed again. This time the Emissary was ready. Leaping and swinging huge talons in a scything arc, it tore the cockpit from the gunship and sent it spiralling down the mountainside in flames.
The emissary wheeled and surged with serpentine speed towards Leontus, who was still staggering to his feet. Blood ran down his pale face from a bad scalp wound. Though he fumbled to draw his blade, the Norn Emissary's prey was in no condition to defend himself. The monster reared above him.
The newly arrived golden warriors moved with incredible speed and merciless focus. Those of the Lord Solar's retinue not swift enough to clear a path were smashed aside with bone-breaking force as Trajann Valrois and his Custodians raced to interpose themselves between Leontus and his would-be xenos assassin. The Norn Emissary was just paces from its victim when a hammering volley of bolt fire from the Custodian's guardians spears arrested its charge. The monster staggered then lunged with a shriek, snatching up the nearest Custodian and tearing one arm from his body before swinging him by the other and hurling him away.
Trajann Valoris stepped in and aimed a mighty stroke with the Watcher's Axe that shattered several of the Emissary's talons. The towering xeno-beast feinted back then sprang past Valoris and attempted to snatch up Leontus. The Lord Solar had, by now, recovered his wits, however, and hurled himself backward to escape the monster's grasp. Bodyguards and chanting priests pressed forward, raking the Norn Emissary with fire from lasguns, pistols, and a handful of plasma weapons. The monster swatted its attackers aside like insects and sent broken bodies tumbling across the plaza.
The next instant it reeled and screeched as several Custodians' blades hacked into its flesh. Eyes still fixed unerringly on the retreating Lord Solar, the Norn Emissary lashed about itself with blistering speed. A custodian was borne aloft and ripped bodily in two. Another was kicked so hard that his head cleared the plaza and vanished over the precipice before his blood-spurting body had even toppled. Yet another was stomped into the flagstones, even his toughened bone structure and auramite armour not enough to prevent his death. The golden wall between the Norn Emissary and its prey was thinning.
All the while Leontus defenders and the remaining Custodians were pouring fire into the colossal alien abomination. A scything blow of the Watcher's Axe slit the cable-like tendons of the beast's right ankle and set it limping. A plasma blast - either skullfully placed or incredibly lucky - melted the right side of the Emissary's face into a fused mass of cooked flesh. Bolt rounds fired by Custodians blasted chunks of chitin and showers of ichor from the creature's limbs and body.
Still the Norn Emissary fought on. Its whipping tail broke another Custodian's neck and sent his body cluttering away across the plaza. A final, desperate effort saw the beast hurl itself forward, jaws grasping to close upon Lord Solar Leontus like a trap slamming shut. Yet Valoris was there at the crucial moment, Watcher's Axe swinging in a meteoric arc to embed itself in the side of the Norn Emissary's skull and smash its head aside. The xenos monster crashed to the ground, crushing more than a score of Leontus' aides under its bulk, yet its last strike at the Lord Solar had been fended off by the Captain-General of the Emperor's own bodyguards. Valoris and his one surviving Custodian kept their weapons levelled at the monster as it twitched and heaved, but it did not try to rise again. Ichor flooded from its grievious wounds, steaming as it cooled and began to freeze upon the cracked flagstones of the plaza.
Lord Solar Leontus looked gravely around at the carnaged, then up at the stern-faced demigod who had interceded to save his life. Expression sombre, Leontus raised his hands and wordlessly offered the Captain-General of the Adeptus Custodes the sign of the Aquila. Valoris returned the gesture, and then calmly set about checking his wargear and reloading the Eagle's Scream. The life of the Lord Solar had been saved at terrible cost, and the defenders of Sanctum had received reinforcements, but there was still a world's worth of war to be waged.
Becoming a daemon is becoming a being made of nothing. He is an emotion made manifest. The Nails are part of him, forever. Even if he changes form or rips them out the damage they did to his psyche is permanent and fundamental to his existence as a Daemon of Khorne.