Hydros

Segmentum: unverified
Designation: Pre-Compliance Xenos World
Classification: Perdita Obscura – uncontacted, anomalous ecology
Tithe Grade: None (pre-Imperial)
Population Estimate: 20–30 million (feral human stock)

Planetary Overview

Hydros Metallica is a world unlike any other catalogued by Imperial cartographia. Its surface is dominated not by water but by a vast and glistening ocean of molten metals — primarily gallium, indium, and heavier alloys — upon which drift titanic rafts of lithic crust. These “mountain-islands” are porous, yet buoyant, supporting soils, forests, and rain-fed lakes. Each raft is a continent adrift, colliding, sundering, and drifting anew across the argent abyss.

The atmosphere is heavy but breathable, enriched by photosynthetic flora that cling to the highlands. Clouds are seeded by oxide dust, giving the skies a peculiar silvery brilliance at dawn and dusk. Lightning storms blaze with metallic light, illuminating the sea’s mirror surface like a world of living quicksilver.

Indigenous Human Population

The human natives of Hydros Metallica have lived in isolation since the Age of Strife. They dwell in stone fortresses atop the floating mountains, eking survival from rain-fed agriculture and the forests that grow in shallow soils.

They are a superstitious and hardened people, their myths bound to the ever-shifting geography. To them, the Mirror Leviathans are living gods of the abyss, and their priests adorn themselves in oxide dust and burn effigies to placate the beasts. Navigation between rafts is a perilous art, for the mountains drift endlessly, and whole settlements are lost when the crusts collide or overturn.

Xenos Threats

The Gallium Sea harbors the dreaded Mirror Leviathans, whose surfacing can obliterate entire settlements. Natives tell of smaller abominations as well — oxide-grazing shoals and crystalline feeders that shimmer beneath the oxide skin, preying on the unwary.

Imperial Assessment

  • Strategic Value: Possible exploitation of gallium–indium resources, but retrieval is complicated by hostile environment.
  • Population: Human baseline, but feral and unlettered. No contact with the wider Imperium; no evidence of psychic mutation reported in intercepted auguries.
  • Hazard: Apex xenos fauna, corrosive oceans, shifting geography. Any attempt at Compliance would require void-naval support and mass orbital resettlement.

Xenos Bestia: Speculum Leviathanum

Classification: Abominable Xenos, macro-piscine entity
Origin: Gallium–Indium abyssal oceans of Hydros
Threat Index: Exterminatus Recommended

“From the argent depths it rises, a cathedral of mirrored scales, and the stars themselves seem reflected in its hide. When it breaks the oxide skin of the sea, whole fortresses are dashed like driftwood. The priests call it a beast, but I name it a continent that breathes.”
– Explorator-Praefectus Lyrandus, last vox-cast before silence

Physical Form

The so-called Mirror Leviathan is a xenos predator of titanic scale, its length rivaling the macro-hulls of void craft. Its body is encased in plates of living ceramo-metallic oxide, refracting light into spectral halos that blind auspex lenses and human eyes alike. Within, its blood is a molten slurry of alien salts, moving with ponderous strength through a lattice of bone-like crystal.

Behaviour & Threat

  • Surface Breach: The creature ruptures the oxide crust of the Gallium Seas to draw oxidants into cavernous siphons. This act alone can sink lesser vessels.
  • Predation: It lurks beneath drifting lithic rafts, striking upward with irresistible force, dragging prey into the suffocating abyss.
  • Weapon of Terror: Its mirrored hide confounds targeting systems, scattering las-beams into impotent coronas of light.

The Legend of the Great Upturning

Hear now the oldest song, carried from raft to raft since the First Drift.

In the beginning the mountains floated gently, borne on the argent sea, and mankind dwelt in their shadows. But the sea is not silent, for beneath its mirrored skin coils the Leviathan Eternal, the Shatterer of Stone.

When the people grow proud and forget the offerings, when the dust of the oxide shrines is left ungathered, the Leviathan will stir. It will thrash its vast coils against the crust of the world. Then shall come the Great Upturning.

Mountains shall capsize as skiffs in a storm. Forests and fortresses will be swallowed, their roots ripped from the soil. Lakes shall pour screaming into the silver abyss, boiling into mist, and clouds will rain ash upon the survivors.

The drifting rafts shall shatter against one another, and whole peoples shall vanish in a single night, ground to dust between the colliding walls of stone. The sky will blaze with argent fire, for lightning is the laughter of the beast, and thunder its roar.

Thus we live in vigil, making sacrifice of oxides and song, lest the Leviathan remember us. Thus we teach our children the terror of the Great Upturning, that they may walk humbly upon the mountains that float for eternity.

Primary Mineral & Material Resources

  • Gallium & Indium Deposits
    • The entire “ocean” is effectively a planetary-scale reservoir of gallium/indium alloys.
    • These metals are rare in most Imperial mining worlds but critical for opto-augmetics, cogitator substrates, and void-ship auspex arrays.
    • Hydros Metallica could supply enough to build entire fleet’s worth of sensorium arrays.
  • Bismuth & Trace Heavy Metals
    • Stable isotopes of bismuth and related alloys are valuable in radiation shielding and plasma weapon casings.
    • The deeper metallic layers may contain exotic isotopes useful in plasma induction coils and warp-field dampeners.

Hydros is a prime mineral world offering gallium, indium, bismuth, and exotic oxides at planetary scale, alongside unique xeno-bioresources. However, the danger of extraction rivals the yield, and only a Rogue Trader with immense resources — or Mechanicus zeal — could ever tame its mirrored seas.