Readouts flickered coldly across the lenses of his helmet. Icons of red and blue flared to life, silhouetted against the curve of a planet. At first he struggled to make sense of the torrent of information, but within a few seconds a coherent picture of the orbital battle took shape. The reserve squadron had formed a wall of steel between the heavy cargo carriers and Jonson's onrushing ships. The Dark Angels' Stormbirds, however, had already raced past the rebel cordon and were even now launching strafing runs on the largely defenceless transports. With the Duchess Arbellatris out of action, Jonson was left with just six ships against eight undamaged enemy cruisers, but the rebel ships were caught at anchor, with little room to manoeuvre against the fast-moving Astartes ships. A salvo of torpedoes was already speeding towards the rebel cruisers' flanks, and the battle barge and her strike cruisers were well within range to open fire with their devastating bombardment cannons. So long as they were committed to protecting the transports, the cruisers were practically stationary targets for the battle group's combined firepower.

No sooner had the ramp sealed shut over Nemiel's re-entry compartment than the whole pod gave a grinding lurch and began to descend into its launch tube. Kohl's gruff, sardonic voice reverberated from Nemiel's vox-bead over the squad net. 'Good to have you join us, brother,' he said sarcastically. 'I was beginning to think you'd gotten lost.'

'We can't all spend our time lounging around in a drop pod, sergeant,' Nemiel said with a chuckle. The pod jolted to a stop with a loud clang, then came the thud of the hatch sealing overhead. 'Some of us have to do proper work so you can live this life of leisure.'

A chorus of deep voices laughed quietly over the vox. Nemiel smiled and glanced over the status readouts of Kohl's Astartes. All nine of the warriors showed green on the display, which was no less than he expected. He had fought alongside them for so long that he'd come to think of them as his own squad, and much preferred their jibes over the deferential respect that most other members of the Legion afforded him.

Kohl began to growl a retort but was cut off by a priority signal over the fleet command channel. 'Battle Force Alpha, this is command,' Captain Stenius called over the vox. 'We are thirty seconds from orbital insertion—' a hollow boom echoed through the battle barge's hull and the signal broke up into squealing static for a second '—are now in contact with Imperial forces on the ground. Inloading new drop coordinates and tactical data to your onboards now. Stand by.'

Seconds later the schematic of the orbital battle disappeared, replaced by a detailed map of a battle-scarred city and the outlying districts of a massive forge complex. The city - identified in the image as Xanthus, Diamat's capital - was built along the shore of a restless, slate-grey ocean, and stretched for dozens of kilometres north and south along the rocky coastline. Twenty kilometres east of the city outskirts, far inland along a desolate plain of black rock and drifts of red oxide, rose the conical slopes of a massive volcano that lay at the heart of the Adeptus Mechanicum's primary forge on Diamat. Many hundreds of years in the past, the scions of Mars had bored into the corpus of the dormant volcano and tapped the geothermal energies within, fuelling the vast smelters, foundries and manufactories that surrounded it. At the far edge of the great plain, the city sprawl and the forge's warehouse complexes met. Squalid subsids and reeking shanty towns fetched up hard against a towering permacrete wall that separated the orderly world of the Mechanicum from the haphazard lives of ordinary humans.

Nemiel took it all in, absorbing every detail with his keenly-trained mind. Icons blinked into life across this grey zone between the city proper and the great forge: blue for the units of the Tanagran Dragoons, and red for Horus's traitors. It took only a moment for the Redemptor to realise that the situation on the ground was desperate indeed.

Xanthus proper had been subjected to prolonged orbital bombardment over the course of several weeks. The city centre was a burnt-out wasteland, and the great, artificial bay of the harbour district was dotted with the hulls of hundreds of broken or capsized ships. To the southeast of the city, connected by tramways to both the city and the great forge complex, lay the planet's primary star port. The port was firmly in rebel hands. Nemiel counted six heavy cargo haulers landed at the site, surrounded by rebel support units and at least a regiment of mechanised troops.

Rebel ground forces had been advancing up the tramway towards the forge complex with four infantry regiments and approximately a regiment of heavy armour, and had apparently managed to break through an Imperial strongpoint covering the forge's southern entrance. There was no data on enemy troop strength or Mechanicum defence forces inside the complex itself. Nemiel suspected that the data had all come from the Imperial forces on-planet, and they had no idea what was going on behind the walls of the Mechanicum preserve.

Blue icons were driving south and east through the grey zone towards the rebels along the tramway; two under-strength regiments supported by a battalion of armour, trying to hit the rebels in the flank and drive them away from the forge. It was a valiant attempt, but the rebels had already stymied the Imperial counter-attack along a rough front some five kilometres north of the tramway.

'Ten seconds to orbital insertion,' Captain Stenius said over the vox. 'Battle Force Alpha, stand by for drop.'

Glowing blue circles appeared on the tactical map, showing the landing zone for the drop. The two companies would come down in a chain of foothills that bordered the very southern edge of the plain, some two kilometres south of the rebel-held tramway. The strategy from there was obvious: the Astartes would advance north and strike the rebels from their other flank, cutting access to the tramway and trapping them against the Imperial forces further north. The elevated terrain south of the tramway provided excellent fields of fire and ample cover for the Dark Angels, allowing them to target the rebel forces at will. Once resistance along the tramway had been eliminated Nemiel reckoned that one company would remain to hold the road against reinforcements approaching from the star port, while the other company would enter the forge complex itself and hunt down any rebel forces operating there.

'Five seconds. Four… three… two… one. Begin drop sequence.'

A massive impact hammered into the Invincible Reason's port side, hard enough to slam Nemiel against this re-entry harness, and everything went black.

Jonson had brought his battle group into Diamat at a fairly steep angle, intending to close with the rebels as rapidly as possible and deploy the landing force. Since the cruisers and the transports they guarded were in geo-synchronous orbits over Diamat's main forge complex, this brought the two forces into point-blank range. Weapons batteries and lance turrets blazed away at the Imperial ships, which responded with a spread of torpedoes and the deadly bombardment cannons of the flagship and her strike cruisers.

The battle barge was wreathed in a hail of explosions as she drove ever closer to the enemy battle-line. At the last moment, the Invincible Reason and her strike cruisers slewed to starboard, almost paralleling the enemy cruisers as the flagship prepared to release its drop pods.

Less than fifty kilometres to port - appallingly close range for a naval engagement - a rebel Armiger-class cruiser raked the battle barge's flank with its heavy lance batteries. Torpedo impacts had gouged deep craters in the Armiger's hull, igniting fires deep in the bowels of the stricken cruiser.