The roar of petrochem engines echoed up a narrow cross-street just twenty metres to the squad's left. Nemiel recognised the sound at once: Imperial military APC's, moving fast. It sounded like four vehicles - a full mechanised platoon.

'Ambush pattern epsilon!' He called out, waving half the squad to the opposite side of the street. Kohl followed after the warriors, his bolt pistol scanning for threats. Brother Marthes knelt behind a pile of blackened rubble to Nemiel's immediate left, bracing his heavy bolter atop the pile. The Redemptor drew his bolt pistol and hit the activation stud on his crozius aquilum. The double-headed eagle atop the staff blazed with crackling blue energies.

The APCs reached the corner in seconds, rumbling fast up the cross-street towards the front line a few more kilometres north. They were lightly-armoured Testudo personnel carriers, armed with a turret auto-cannon and capable of transporting a full squad of troops. Their drivers were going all-out, kicking up thick plumes of black exhaust from their engine decks.

The Dark Angels had gone to ground with admirable speed and skill, concealing their presence behind piles of debris or in the entry niches of several ruined buildings. Just as the APCs appeared, one of the Astartes stepped out of cover and raised the muzzle of his stubby meltagun. Brother Marthes brought the antitank weapon to bear on the flank of the lead Testudo and touched the firing stud, unleashing a blast of high-intensity microwaves that converted the vehicle's metal hull into superheated plasma. The APC's fuel tanks exploded in a ground-shaking whump, blowing the Testudo apart in a shower of blazing fragments.

Brother Vardus opened fire a second later, raking the rear Testudo with an extended burst of heavy bolter fire. The mass-reactive rounds exploded against the APC's armoured hide and gouged craters in its solid tyres. Here and there the rounds found a seam in the armour plates and penetrated into the APC, wreaking bloody havoc on the men crammed within. The Testudo lurched to a stop, smoke pouring from the holes punched in its side.

The two middle APC's swerved left to try and avoid the burning wreck of the lead vehicle and escape the kill zone. Their turrets slewed to the right and spat a stream of high-explosive shells down the street, blasting more holes into the burnt-out buildings and digging up sprays of permacrete from the rubble piles. Brother Marthes switched his aim and fired at the next APC in line, but this time his shot went a little high, striking the vehicle's small turret and ripping it open. Autocannon shells cooked off in the blast of heat, wreathing the Testudo's upper deck in angry flashes of red, and the APC abruptly lost speed. The second Testudo, moving too fast to stop, rear-ended the damaged vehicle and spun it ninety degrees to the right, nearly flipping it over.

Vardus levelled the heavy bolter at the two immobilised APCs and hammered them with short, precise bursts. Nemiel watched the rear ramp of the second Testudo come down and raised his bolt pistol. As the panicked squad fled from the stricken vehicle, he and the rest of the squad cut them down with a volley of bolter fire. The last of the rebels had yet to hit the ground when Marthes fired another shot at the damaged APC, this time scoring a direct hit and immolating the men trapped inside.

It was a far cry from the old tales of chivalry he'd been taught on Caliban, Nemiel thought, surveying the carnage with clinical detachment. War was about butchery, plain and simple. Notions of glory came long afterward, he'd come to realise, imagined by those who had never seen the reality with their own eyes.

Nemiel's vox-bead crackled to life. 'All units, location and status check,' Force Commander Lamnos said tersely.

Brother-Sergeant Kohl and two other squad members dashed down the street to check the wrecked vehicles and ensure there were no survivors. Nemiel called up a map of the landing zone on his tactical display and checked his coordinates. They'd come down just a kilometre and a half north of the tramway, close to the forge's southern entrance. 'This is squad Alpha Six. Status is green. Awaiting orders,' he replied, providing their coordinates.

'Affirmative, Alpha Six. Stand by,' Lamnos answered at once. Less than a minute later the Force Commander came back. 'Alpha Six, we're getting a signal that Echo Four's pod is down but failed to deploy. Enemy forces are closing in on Echo's location from the south. Link up with Echo Four and ascertain its status immediately. Stand by for coordinates.'

Nemiel compared the coordinates to his tactical map. Echo Four had come down half a kilometre to the southeast, closer to the forge complex. 'We're on our way. Alpha Six out,' he replied.

Kohl and his warriors returned from the killing ground. 'There's mechanised infantry with Testudo APCs coming up the street from the direction of the tramway,' he reported.

'They'll have to wait,' Nemiel said. 'We're heading east. Echo Four is in some kind of trouble; the pod probably came down inside another building, and the ramps won't deploy. We've got to get there before the rebels do.'

Kohl nodded his helmeted head and addressed the squad. 'Askelon, you wanted a nice walk in the sunshine, so don't let me hear you crying if you can't keep up. Brother Yung and Brother Cortus, you're on point. Let's move!'

Without a word the squad rose from cover and set off east down the street, their boltguns sweeping ahead and to the flanks in search of targets. Nemiel fell into step with Techmarine Askelon and Brother Marthes beside him, while Kohl and three other squad members brought up the rear. Farther east, the grey wall of the forge complex rose above the smoking ruins of the grey zone. Tall, blinking towers made a metal forest beyond that forbidding barrier, girding the flanks of the bound volcano at the heart of the Mechanicum's domain. Plumes of orange and black smoke hung heavily about the complex, giving the place a nightmarish cast.

We came all this way to defend that? Nemiel grinned ruefully within the confines of his helmet. It hardly seemed like the kind of place worth dying for.

'This is Epsilon Three-Niner Heavy, lifting from zone four! I'm taking fire!'

The panicked vox-transmission cut through the hectic buzz of conversation in the fortress strategium, tearing Zahariel's attention from the glowing panes of after-action reports projected above his desk. Gritting his teeth, he blanked his hololith display and stepped swiftly from his office into the bustling chamber beyond.

It was mid-afternoon of the fourteenth day since the insurgents' global campaign began and so far the violence showed no signs of abating. The strategium had been in constant operation ever since, staffed by a mix of Legion officers and aides and senior commanders of the Jaeger regiments in action across Caliban. The men and women of the Jaegers struggled to cope with the constantly shifting nature of the enemy attacks, and the pressure of maintaining civil order while simultaneously trying to come to grips with insurgent cells that avoided direct combat as much as possible. They consumed pots of bitter tea and stim capsules and tried to match the stoic calm of the Astartes that loomed in their midst, but he could feel their frustration as the cargo hauler's distress call broadcast from the vox-unit across the room. Zahariel caught sight of Luther standing near the vox-unit, listening intently. So far as he knew, the Master of Caliban hadn't left the strategium for days on end.

A new voice crackled over the vox as Zahariel worked his way across the chamber. He heard a Legion air defence controller say, 'Epsilon Three-Niner Heavy, be advised, combat air patrol has been alerted and is vectoring on your position. Time to rendezvous is thirty seconds. What are you seeing?'