I quite like it, and I think it might make a good intro to a novella or a long short story that I might work on as a bit of writing practice. Anyway, hope you enjoy it - all criticism is very welcome.
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The Iapetus fell from the sky with all the ponderous grace of a god’s descending hammer.
Massive even on the scale of void-going ships, it dwarfed the slender orbital rings and intra-system guard ships that crowded Tartunn’s orbit. A fat-bellied leviathan born to wallow through the deep spaces between stars, it dropped past these slighter vessels, its bulk absorbing their desperate fire.
One unfortunate vessel, the system ship Ultrenen, was caught in its path, held within a colossal web of scaffolding that blossomed from Tartunn’s primary dry-dock. A full kilometre from prow to stern, it had guarded the space between the system’s three planets for sixteen centuries. Its hull bore the scars and honours of Imperial service, blackened and pockmarked by weapons fire. It was home to two thousand crew and slaves.
The Iapetus’s armoured prow struck the Ultrenen in the centre of its spine. Fluted spires and towers crumpled instantly as the full, impossible mass of the Iapetus struck the Ultrenen's main hull. The smaller ship disintegrated. Thick steel stays shattered like glass. Hull plating sheared like vellum under a knife. The crew who died instantly were the fortunate ones, crushed by the unseen hammer blow that descended upon them. The few that survived were broken against bulkheads as up and down became meaningless in the tumbling wreckage.
The Iapetus passed through its victim with malignant indifference. Its true target lay below.
The enormous vessel’s void shields caught fire as the Iapetus struck Tartunn’s atmosphere. They flared, burning with kaleidoscopic colour as they met titanic resistance, as though the planet herself was fighting to repel the brute invader. Retrograde engines along its hull began to fire, introducing another element into the violent equation of re-entry.
With a final burst of unnatural light the void shields failed, and even so mighty a ship as the Iapetus could not fail to shudder as the full force of atmospheric entry struck it. But the shields had done their work, and through the ventral hull burst into flame and the vessel trembled, it continued to slow, a burning omen that seared Tartunn’s sky with its passage.
Tartunn was a world like many others in the vast Imperium of Man. Possessed of a temperate, stable biosphere, it had no particular mineral wealth nor an abundance of any other resources of note, and so it had been spared the predations of the Adeptus Mechanicus’ insatiable hunger. Instead, it had been allowed to grow and prosper over the millennia into a minor hub for sub-sector trade and production. The majority of its population were clustered together in vast sprawl cities, toiling in factorums or owning them, depending on the vagaries of birth. Much of the rest were scattered across the eastern hemisphere in towns and cities whose principal functions were agricultural and agronomical, feeding the unquenchable appetite of the hives. A few of its scholams were recognised as centres of great accomplishment in the sub-sector, producing leaders of war and captains of industry.
These points mattered little to those aboard the Iapetus as it dropped from the night sky, haloed by the light of straining re-entry engines. All they cared was that Tartunn had a population of six billion people. Six billion citizens of the Imperium. Six billion servants of the Throne of Terra.
And for that reason alone, Tartunn would die.