Salamanders were tossed into the air with chunks of rockcrete chewed out of the road, and fell like debris.

‘Close ranks. Hold positions,’ Tsu’gan snarled, crouching down next to a partially destroyed barricade once occupied by Stratosan Aircorps.

Iagon shoved one of the bodies out of the way, so he could rest his bolter in a makeshift firing lip.

‘Still nothing from the captain,’ he said between bursts.

Tsu’gan’s reaction to the news was guarded, his face fixed in a perpetual scowl.

‘Ul’shan,’ he barked to the sergeant of the Devastators, ‘all fire on that tank. In the name of Vulkan, destroy it.’

Bolter fire pranged against the implacable vehicle, grinding forwards as it readied for another shot with its battle cannon. In the turret, a crazed cultist took up the heavy stubber and started hosing the Salamanders with solid shot.

‘You others,’ bellowed Tsu’gan, standing up and unhitching something from his belt, ‘grenades on my lead.’ He launched a krak grenade overarm. It soared through the air at speed, impelled by Tsu’gan’s strength, and rolled into the tank’s path. Several more followed, thunking to earth like metal hail.

At the same time, Iagon’s bolter fire shredded the cultist in the stubber nest, whilst Sergeant Ul’shan’s heavy bolters hammered the tank’s front armour and tracks. An explosive round from the salvo clipped one of the krak grenades just as the armoured vehicle was driving over it. A chained detonation tore through the tank as the incendiaries exploded, ripping it wide open.

‘Glory to Prometheus!’ roared Tsu’gan, punching the air as his warriors chorused after him.

His fervour was dampened when he saw shadows moving through the smoke and falling shrapnel. Three more tanks trundled into view.

Tsu’gan shook his head in disbelief.

‘Mercy of Vulkan…’ he breathed, just as the comm-link with Captain Kadai was restored. The sergeant glared at Iagon with iron-hard eyes.

They were falling back to Aereon Square.

Dak’ir had been right. Tsu’gan felt his jaw tighten.

‘Hold the line!’ Kadai bellowed into the comm-feed. ‘We make our stand here.’

The Salamanders held position stoically, strung out across the chewed-up defences, controlled bursts thundering from their bolters. Behind them were the armoured transports. Storm bolters shuddered from turret mounts on the Rhinos and Fire Anvil’s twin-linked assault cannon whirred in a frenzy of heavy fire, though the Land Raider’s flamestorm side sponsons were powered down.

The Salamanders had converged quickly on Aereon Square, the fighting withdrawal of the three assault groups less cautious than their original attack.

The slab floor of the square was cratered by bomb blasts and fire-blackened. Fallen pillars from adjacent buildings intruded on its perimeter. The centre of the broad plaza was dominated by a felled statue of one of Stratos’s Imperial leaders, encircled by a damaged perimeter wall. It was here that Kadai and his warriors made their stand.

The cultists came on in the face of heavy fire, swarming from every avenue, every alcove, like hell-born ants. Hundreds were slain in minutes. But despite the horrendous casualties, they were undeterred and made slow progress across the killing ground. The corpses piled up like sandbags at the edge of the square.