The Aggressors stomped forwards, their Gravis-pattern armour protecting them in the teeth of the Death Guard’s fire. They returned fire as they advanced, rockets shrieking from their backs on needles of white heat. The loading mechanisms in the weapons clunked repetitively as they replenished their racks from the Aggressors’ internal ammo stores. Plumes of fire billowed from their flame gauntlets, drenching everything with burning promethium. The diffuse air’s oxygen content was low and the wood was wet, but the tenacity of the promethium fire was such that soon tranches of the corrupted woodland were smouldering, helped by the blast-furnace roar of escaping atmosphere, and greasy smoke joined the yellow fog in its hurried exit through the dome breach.

There was a squad of seven Plague Marines holding the exit to the park. They sheltered behind a black tree that had fallen over the path. More plants, slippery with decay, coated the block paving. Movement in the woods either side of the main path had Felix bring up his visual filters, his false-colour heat sense revealing more of the enemy attempting to encircle them. One of the Plague Marines was blasted backwards by the combined fire of an entire Intercessor squad. He remained upright as he was pummelled, his guts hanging in dripping loops from a new rent in his rotten plate. A Hellblaster spotted the traitor’s survival, and, with a quickly aimed stream of plasma, put him down for good.

‘Hellblaster squads Alpha and Beta – take out designated enemy squads on the flanks,’ said Felix, exloading the targeting data to his warriors. ‘Intercessor squads, prepare to charge. Aggressor squads, burn out the enemy blocking our egress.’

Away to the right, a ball of brilliant blue lightning burst amid the trees, shaking the failing dome with psychic thunder. Codicier Maxim held up his hand, rotating his fingers, and the thunderball turned with them. As he clenched his fist, the ball lightning collapsed with a second peal of thunder, taking with it all matter that had occupied the space, leaving a perfectly spherical hole in the diseased forest.

‘They are falling back,’ voxed Hellicus, one of his Intercessor sergeants. Unbidden, Felix’s cogitator projected the warrior’s name and vital signs across his helm display, highlighting his location on the cartograph projected into his eyes, along with status updates on his armour integrity and ammunition count. A combat-effectiveness estimate blinked a steady green at one hundred per cent capability.

‘We follow,’ said Felix. ‘Now!’ He ran out from around the statue and drew his power sword.

The Plague Marines fired as they fell back squad by squad. Their lumbering movements acquired a certain crispness as they withdrew, an echo of martial training similar to his own, and Felix had a glimpse of the warriors they had once been – not so very different to himself.