The Warmaster turned to Verulam Moy and said, 'Try and raise Erebus,' before returning to his own attempts at communication. 'Little Horus, can you hear me?'

More static followed, uninterrupted save for a faint voice, '…ordnance deck… slow… shells. Making safe… but… make… gress.'

'Nothing from Erebus,' reported Moy, 'but he may be on the other side of the ship by now. If the interference we are getting between our own warriors is anything to go by, it is unlikely our armour links will be able to reach him.'

'Damn it,' repeated the Warmaster. 'Well, let's keep going.'

'Sir,' ventured Moy. 'Might I make a suggestion?'

'If it's that we turn back, forget it, Verulam. My honour and that of the Crusade has been impugned and I'll not have it said that I turned my back on it.'

'I know that, sir, but I believe Captain Loken is correct. We are taking a needless risk here.'

'Life is a risk, my friend. Every day we spend away from Terra is a risk. Every decision I make is a risk. We cannot avoid risk, my friend, for if we do, we achieve nothing. If the highest aim of a captain were to preserve his ship, he would keep it in port forever. You are a fine officer, Verulam, but you do not see heroic opportunities as I do.'

'But, sir,' protested Moy, 'we cannot maintain contact with our warriors and we have no idea what might be waiting for us in this ship. Forgive me if I speak out of turn, but delving into the unknown like this does not feel like heroism. It feels like guesswork.'

Horus leaned in close to Moy and said, 'Captain, you know as well as I do that the whole art of war consists of guessing what is on the other side of the hill.'

'I understand that, sir—' began Moy, but Horus was in no mood for interruptions.

'Ever since the Emperor appointed me in the role of Warmaster, people have been telling me what I can and cannot do, and I tell you I am sick and tired of it,' snapped Horus. 'If people don't like my opinions, then that's their problem. I am the Warmaster and I have made up my mind. We go on.'

A squealing shriek of static abruptly sliced through the darkness and Luc Sedirae's voice came over the armour link as clearly as if he stood next to them.

'Throne! They're here!' shouted Sedirae.

Then everything turned upside down.

Loken felt it through the soles of his boots as a tremendous rumbling that seemed to come from the very foundations of the moon. He turned in horror, hearing metal grind on metal with a deafening screech, and watching geysers of mud spout skyward as buried portions of the starship tore themselves free of the sucking mud. The upper sections of the vessel plummeted towards the ground and the entire ship began tipping over, the colossal rear section arcing downwards with a terrible inevitability.

'Everyone get clear!' bellowed Loken as the massive weight of metal gathered speed.

Astartes scattered from the falling wreck, and Loken felt its massive shadow like a shroud as his armour's senses shut out the roaring noise of the starship's collapse.

He looked back in time to see the wreckage slam into the ground with the force of an orbital strike, the superstructure crumpling under the impact of its own weight and hurling lakes of muddy water through the air. Loken was tossed like a leaf by the Shockwave, landing waist deep in a stagnant pool of greenish scum and disappearing beneath the surface.

Rolling to his knees, he saw tsunamis of mud rippling out from the vessel, and watched as dozens of his warriors were buried beneath the brownish sludge. The power of the wrecked starship's impact spread from the crater it had gouged in the mud. A brackish rain of muddy water drizzled down, smearing his helmet's visor and reducing visibility to no more than a few hundred metres.

Loken climbed to his feet, clearing the action of his bolter as he realised the Shockwave had dispersed the sulphurous fog that had been their constant companion since landing on this accursed moon.

'Sons of Horus, stand ready!' he shouted, seeing what lay beyond the fog.

Hundreds of the dead things marched relentlessly towards them.

Not even the armour of a primarch could withstand the impact of a falling starship, and Horus grunted as he pulled a twisted spar of jagged iron from his chest. Sticky blood coated his armour, the wound sealing almost as soon as he had withdrawn the metal. His genhanced body could easily withstand such trivial punishment, and despite the spinning fall through the decks of the ship, he remained perfectly orientated and in balance on the sloping deck.

He remembered the sound of tearing metal, the clang of metal on armour and the sharp crack of bones snapping as Astartes warriors were thrown around like children in a funhouse.

'Sons of Horus!' he shouted. 'Verulam!'

Only mocking echoes answered him, and he cursed as he realised he was alone. The vox mic on his gorget was shattered, brass wires hanging limply from the empty socket, and he angrily ripped them away.

Verulam Moy was nowhere to be seen, and his squad members were similarly scattered beyond sight. Quickly taking stock of his surroundings, Horus could see that he lay partially buried in metal debris on the armorium vestibule, its ceiling bulging and cracked. Icy water dripped in a cold rain, and he tipped his head back to let it pour over his face.

He was close to the bridge of the ship, assuming it hadn't sheared off on impact with the ground - for surely there could be no other explanation for what had happened. Horus hauled himself from beneath the wreckage and checked to make sure that he was still armed, finding his sword hilt protruding from the detritus of the vestibule.

Pulling the weapon clear, its golden blade caught what little light there was and shone as though an inner fire burned within its core. Forged by his brother, Ferrus Manus of the Tenth Legion, the Iron Hands, it had been a gift to commemorate Horus's investiture as Warmaster.

He smiled as he saw that the weapon remained as unblemished as the day Ferrus had held it out to him, the light of adoration in his steel grey eyes, and Horus had never been more thankful for his brother's skill at the forge's anvil.

The deck creaked beneath his weight, and he suddenly began to question the wisdom of leading this assault. Despite that, he still seethed with molten rage for Eugan Temba, a man whose character he had believed in, and whose betrayal cut his heart with searing knives.

What manner of a man could betray the oath of loyalty to the Imperium?

What manner of base cur would dare to betray him?

The deck shifted again, Horus easily compensating for the lurching motion. He used his free hand to haul himself up towards the gaping doorway that led to the warren of passageways that riddled a ship this size. Horus had set foot on the Glory of Terra only once before, nearly seventy years ago, but remembered its layout as though it had been yesterday. Beyond this doorway lay the upper gantries of the armorium and beyond that, the central spine of the ship that led through several defensive choke points to the bridge.

Horus grunted as he felt a sharp pain in his chest and realised that the iron spar must have torn through one of his lungs. Without hesitation, he switched his breathing pattern and carried on without pause, his eyesight easily piercing the darkness of the vessel's interior.

This close to the bridge, Horus could see the terrible changes wrought upon the ship, its walls coated in loathsome bacterial slime that ate at the metal like an acidic fungus. Dripping fronds of waving, leech-like organisms suckled at oozing pustules of greenish brown matter, and an unremitting stench of decay hung in the air.

Horus wondered what had happened to this ship. Had the tribes of the moon unleashed some kind of deadly plague on the crew? Were these the means that Erebus had spoken of?