The Redemptor keyed his vox. 'Brother Titus, are you and the rest of the squad in position?' he called.

'Affirmative,' the Dreadnought replied in his metallic voice. 'I have you on my surveyors now.'

'Very well,' Nemiel said. 'Fire at will.'

Two hundred metres north, at exactly the same spot where Kohl and Nemiel had reconnoitred the fortifications a half-hour before, Brother Titus stepped around the corner of the burnt-out building and readied his assault cannon. The weapon's six barrels began to spin with the ominous, rising whine of electric motors until they were little more than an iron-grey blur. The Dreadnought surveyed the enemy positions with a single sweep of his sensor turret and fired a long, roaring burst.

Diamantine-tipped, light armour-piercing rounds raked across the northern bastion and then down along the parked APCs. The shells blasted craters in the formed permacrete; enemy troops caught in the open were literally blown apart by the high-velocity projectiles. The rounds punched through the thin armour of the easternmost APCs turret and touched off one of the shells in the ammo feed; it blew apart in a yellow fireball and filled the vehicle with a storm of deadly shrapnel.

The remaining warriors in Kohl's veteran squad fanned out around the Dreadnought and began advancing across the no-man's-land toward the bastions, firing as they went. Their shots added to the storm of shells and drove the stunned rebels behind the nearest cover.

The turrets of the three surviving Testudos quickly swerved to target the threat bearing down on them from the north. 'It's working!' Brother Marthes shouted. 'They're going after Titus!'

'Let's not leave him hanging any longer than we have to,' Nemiel replied. 'Increase speed!'

The two APCs roared down the tramway at full throttle, seemingly racing for the safety of the fortifications around the gateway. As they drew close to the parked rebel vehicles, a sergeant rose to a crouch and began pointing urgently to positions alongside the berm, but both of the Testudos shot right past.

'Uh, Brother-Redemptor Nemiel?' Marthes said. 'You didn't mention anything about a barricade between the two fortifications.'

'We couldn't see between the fortifications during our reconnaissance,' Nemiel answered. 'Can we break through?'

'We're about to find out,' the Astartes said grimly. 'Brace for impact!'

A second later the Testudo struck a pair of permacrete construction barriers that had been laid across the entrance to the forge. There was a tremendous crash, and a grinding of metal on stone, and the forty-tonne APC bucked skyward like a broaching whale as its sloped bow carried it over the lip of the barricade. There it might have remained, had not the second APC crashed into it from behind.

The impact shoved the Testudo further forward, bearing over the barricade and forcing it into the gap beside the two bastions. The APC came to a stop, bow dragging across the tramway after having its front two wheels ripped completely away.

'Lower the ramp!' Nemiel shouted. Outside he could hear urgent shouts and the crack of lasguns.

He heard a hollow booming at the back of the troop compartment, then a grating of metal as Brother Ephrial forced the partially-jammed ramp open. The sounds of battle flooded into the compartment: angry shouts, the crackle of las-bolts, the distant snarl of the Dreadnought's assault cannon and the hollow bark of boltguns. Las-bolts began to strike the side of the APC in a staccato hail of small explosions.

Ephrial forced his way out of the wrecked Testudo and opened fire, snapping off short, controlled bursts at the ramparts of the bastion to the north. Cortus was next in line, and made it out significantly faster thanks to having enough room to throw himself against the ramp and drive it a bit further to the ground. A las-bolt struck him a glancing blow across the back of the helmet as he emerged into the open; he shook his head like an angry bear and struggled to his feet, his bolter spitting death at the rebels.

'Marthes! Let's go!' Nemiel shouted.

The Redemptor clawed his way forward, his crozius clutched in his fist. He emerged into a veritable storm of fire from both sides of the gateway, and found himself staring at the sight of Brother-Sergeant Kohl's APC, lying on its right side atop the crushed remains of the barricade. The Dark Angels had succeeded in deploying their ramp and were now trading shots with the rebels in the southern barricade from behind the shelter of the wrecked vehicle.

Nemiel drew his bolt pistol and headed right, firing shots up at the ramparts of the northern bastion as he went. The fortification was like a three-storey stepped pyramid, with a rampart and firing positions at each level. Unfortunately for the rebels, there was only a narrow frontage that actually looked down into the space between the fortifications; the defences were designed primarily facing outward, covering the hundreds of metres of kill zone and the long, wide tramway. Rebel troops were now crowded along those narrow ramparts, pouring lasgun fire down at the Astartes, but the Dark Angels were taking a fearsome toll of the bunched-up troops.

'Brother-Sergeant Kohl, get your section moving!' Nemiel called over the vox. 'Ephrial! Cortus! With me!'

He ran stiff-legged towards the far end of the bastion, close to the actual gateway. As he expected, there was a ramp leading up into the fortification proper. 'Grenades!' he ordered. Ephrial and Cortus immediately pulled a pair of fragmentation grenades from their belt dispensers, set the fuses and threw them up and over the first-level rampart. Nemiel was already charging up the ramp, bolt pistol ready.

The grenades went off with a pair of muffled bangs and a chorus of agonised shouts and screams. Nemiel reached the top of the ramp; it turned sharply to the right, opening onto the first rampart. It was a standard Imperial fortification, right out of the field manual, and he knew its layout well. He rounded the corner, firing his bolt pistol and charging the stunned rebels with a fierce battle cry.

The rampart was a scene of carnage. Dead and wounded men were slumped at the base of the narrow, trench-like passage, shredded by bursts from the Dreadnought's assault cannon or blown apart by mass-reactive bolter shells. The survivors retreated down the length of the rampart, firing wildly as they staggered over the bodies of their comrades. More las-bolts rained down from the ramparts above; they detonated against his armour's broad pauldrons or glanced from the top of his curved helm. Nemiel kept moving forward, firing methodically and killing a soldier with each well-placed shot. Ephrial and Cortus joined him in moments, firing up at the higher ramparts to suppress the enemy fire.

The rampart ran for fifteen metres due west, then doglegged sharply to the north-east. At the corner, Nemiel paused and threw a grenade of his own, then followed right on the heels of the blast. Several metres behind him, he heard the shrieking blast of a meltagun, and knew that Marthes had joined them at last.

Around the corner the rampart ran for more than forty metres in a straight line, its weapon emplacements looking out over the killing ground that Brother Titus and the rest of the squad were currently advancing across. The parapet here had been savagely chewed by the Dreadnought's assault cannon and Brother Marthes's heavy bolter, and there were far more dead rebels than live ones still holding the trench. Fifteen metres down the line another ramp led up and back to the second level.

The rebels fell back a bit further in the face of Nemiel's advance, but held their ground rather than give up the next ramp. They poured fire from their lasguns at the advancing Astartes, but the las-bolts were meant for lightly-armoured humans, not walking juggernauts like the Dark Angels. Nemiel advanced doggedly into the whirlwind of fire, pummelled by shot after shot. Warning icons flashed insistently on his helmet display, and he overrode each and every one. Gathering his strength, he charged the last ten metres until he was in close-combat range. Then the slaughter truly began.