'The defence of Caliban is not a matter for the Adeptus Terra to concern itself with,' he said in a stern voice. 'And our primarch has more important matters to occupy his attentions at present. Master Luther explained to you that he was waiting for the proper time to order our battle brothers into action, and clearly that moment has arrived.'

Luther turned to Zahariel as the Librarian spoke, and the two warriors locked eyes. The Master of Caliban glared at the Astartes for a moment, his dark eyes glittering with anger. Zahariel met the knight's gaze steadily.

After a moment, Luther seemed to master his anger. He nodded slowly, though his expression was still deeply troubled.

'Well said, brother. Assemble a squad of veterans and depart for Sigma Five-One-Seven at once. Eliminate any resistance and secure the site, then report back to me. Understood?'

Inwardly, Zahariel breathed a sigh of relief. He regretted having forced Luther's hand, but he was certain that, in time, the Master of Caliban would forgive him. The Librarian bowed to Luther, then nodded respectfully to General Morten and Magos Bosk before striding purposefully from the room.

His conscience was clear. For the sake of the Emperor and the honour of the Legion, the Dark Angels on Caliban were rousing themselves for war.

SEVEN

Brothers in Arms

Nemiel's squad raced down the narrow street towards the location of Echo Four's downed pod, expecting to encounter more rebel troops at any moment. Sounds of fighting between Astartes squads and enemy forces echoed across the grey zone with increasing intensity as the rebels began to respond to the danger in their midst. Nemiel heard the bark of autocannons and, here and there, the flat boom of a tank's battle cannon adding to the din.

'Turn south at the next corner,' he called out to his squad. 'Echo Four should be another four hundred metres down the cross-street and somewhere to the left.'

'Acknowledged,' said Brother Yung, one of the two warriors on point. Nemiel watched the Astartes race up to the street corner and put their backs to a burnt-out storefront, their bolters held across their chests. One of the two warriors - Brother Cortus, Nemiel thought - slid to the end of the wall and peered around the corner.

Nemiel heard the battle cannon fire and watched the corner of the building Coitus was standing at disintegrate in the space of a single heartbeat. The two Astartes disappeared in a blizzard of pulverised stone and fragments of structural steel. A billowing cloud of dust and smoke enveloped the intersection and rolled down the street towards the rest of the squad.

The squad took cover on reflex, crouching behind rubble piles or pressing close to a building wall. Nemiel checked his helmet display and saw the status icon for Brother Cortus flash from green to amber. He was wounded, perhaps seriously, but still functional. The walls of the building must have shielded the Astartes from the worst of the blast.

Less than a minute later Brother Yung emerged from the smoke cloud, his black armour caked with brown dust. He was half-carrying, half-dragging Brother Cortus. Nemiel rose from cover and jogged forward as Yung set the wounded warrior down next to the shattered stoop of a hab unit.

Cortus reached up and fumbled with his helmet. One side of the ceramite helm had been partially crushed, shattering the right ocular and splitting it from crown to nape. Yung lent a hand and helped the wounded Astartes pull the helmet free.

'Status?' Nemiel asked.

Brother Cortus sent the smashed helmet bouncing across the street. The skin on the right side of his face had been deeply scored by the impact, peeling away the flesh down to the bone in some places. His right eye was a bloody ruin, but the wound was clotting quickly thanks to Cortus's enhanced healing ability.

'One battle tank and four APCs, three hundred metres south,' he said, his voice rough with pain. 'Approximately a platoon of infantry in hasty defensive positions, maybe more.'

'I was talking about your head, brother.'

Cortus glanced dazedly at the Redemptor, blinking his one good eye. 'Oh, that,' he said dismissively. 'It's nothing. Did anyone see what happened to my bolter?'

'Here,' Yung said laconically, handing over Cortus's dirt-caked weapon.

The wounded warrior's face brightened. 'Thanks for that, brother,' he replied. 'Kohl would have had my skin if I'd lost it.'

'Too right,' Sergeant Kohl growled as he crouched down beside Nemiel. 'It sounds like the rebels have beaten us to Echo Four,' he said to the Redemptor. 'We might already be too late.'

'Or perhaps we're just in time,' Nemiel countered. 'Three hundred metres is too far away to have a good chance at a kill with the meltagun. We'll have to get closer.' He looked back down the way they'd come, searching for an alley they could use to outflank the enemy position, but there was none. 'We'll have to cut through the buildings,' he decided. 'Sergeant, you and Askelon lead the way.'

Kohl nodded and beckoned to the Techmarine. Nemiel helped Cortus to his feet, then followed the sergeant through the hab unit's gaping doorway.

It took ten minutes for the squad to work its way through the partially-collapsed structure. Kohl and Askelon ploughed through any rubble in their path; in places the Techmarine used his servo arm to reinforce damaged structural supports so that the squad could keep moving without touching off a cave-in. They emerged from the building via a broken out viewport, crossed a narrow, filth-strewn alley, and entered the shell of another structure on the far side.

The second building had almost completely caved in, forcing the Astartes to scramble over enormous piles of rubble to reach the opposite side. Nemiel could hear the idling rumble of petrochem engines now, and the distant sound of shouted orders.

They reached the crest of a rubble pile close to the far corner of the building and hunkered down. Nemiel joined Kohl and Askelon, and peered over the top of the pile. By this point, his armour was so caked in dust that it was nearly invisible against the backdrop of debris.

He could see the enemy positions through the tall, broken viewport frames at the corner of the ruined structure. The battle tank was parked in the centre of another intersection, its flanks wreathed in exhaust fumes. The four APCs were arrayed behind it in a loose formation; their ramps were down and their troops had deployed into cover on either side of the street. At the opposite corner of the intersection stood a ruined hab unit with a huge, ragged hole high on the side of one of its upper storeys. Flames licked hungrily about the hole.

'We've found Echo Four,' Nemiel announced over the vox. 'Vardus, set up your shot. Everyone else, get ready to move.'

Brother Vardus worked his way up the rubble pile and aimed his meltagun through the viewport frame at the tank. The rest of the squad climbed up the slope to either side, their weapons ready.

The meltagunner glanced at Nemiel and gave a nod.

'Fire!' Nemiel said.

The meltagun went off with a hissing shriek of superheated air and struck the tank in the side, right beside the engine. Molten pieces of armour plate and track segments went spinning through the air. Nemiel surged to his feet.

'Loyalty and honour!' the Redemptor cried. 'Charge!'

With a shout, the Dark Angels scrambled down the rubble pile and leapt through the open viewport frames, their boltguns blazing. Rebel troops tumbled to the ground, their light armour no match for the bolters' powerful rounds, but the survivors immediately returned fire. Lasgun rounds buzzed through the air, detonating against the sides of the blackened buildings with a staccato crackle.