The Under-Earth of the Long War

THE UNDERWAR REALM A century ago, the sun was swallowed by a war that should have ended in a season but metastasized into a grotesque ritual. This is Earth, but not the one that ever made it into our history books. Mana seeped up through the crust like groundwater; alchemists weaponized it before philosophers could even argue about ethics. The first shells screamed through the sky in 1914. The sky hasn’t been seen since 1928. Magically-enhanced mustard gas, “Mirewind,” turned the surface into a shimmering golden death fog. Birds dropped out of the air, oceans hissed like boiling kettles, forests wilted into lacquered bone. Anyone aboveground suffocated, hallucinated, or rotted alive. Humanity burrowed. What followed was the Age of Tunnels. Not trenches. Not foxholes. A full planetary anthill war.

THE TWO TITANS The Old Empire Gas masks brittle. Ammunition nearly lore. Ventilation systems coughing like dying lungs. Morale a threadbare quilt of duty, superstition, and desperate pride. Once glorious, now draped in soot and hunger. Aesthetic Medieval-futuristic scraps. Plate cuirasses reinforced by bolted boiler plates. Spears tipped with repurposed bayonets. Helmets etched with faded sigils meant to ward off magic poisoning. Magic Access Weak, flickering. Their mages have largely died or defected. Rely on “death magic” — scavenged residues, rituals meant to stabilize structures, fortify bodies, or make blades bite through armor. Condition Living quarters cramped to the point of madness. Children grow pale and long-boned from underground life. Water tastes like rust and fungus. Ventilation systems groan constantly, cycling in just enough air to avoid suffocating. Roles Unique to Old Empire

1. Lanternbearers Children or teens with mild magical sensitivity who can “sense” gas pockets, structural weaknesses, or enemy tunneling through psychic vibrations. They carry whale-oil lamps and wear bone necklaces that rattle at certain frequencies. Half revered, half pitied.
2. Rotwardens Sanitation knights. Their job: stop disease from wiping out entire cavern towns. They wield hooked staves, cleaning charms, and fire spells to burn filth. Also the ones who cremate the fallen.
3. Ironskalds Tunnel bards. They coordinate formations with resonant chants that magically strengthen morale and steel. The magic only works underground. They fight with short picks.
4. Gloom Riders Mounted units on enormous burrowing lizards bred to withstand the toxic haze in deeper caverns. Used for rapid response or raids.
5. Nightforgers Blacksmiths who shape steel in constant darkness using fungi-fire, bio-luminescent forges, and runic molds. Their armor is ugly but nearly indestructible.

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The King’s Faction Tyrannical, iron-controlled, but frighteningly stable. Their propaganda paints them as saviors of order in a chaotic, collapsing world. Their citizens get actual food. Ventilation flows clean. They have lights that don’t flicker. Aesthetic World War I modernity fused with magical industrialism. Steel masks with glowing slits. Long coats reinforced with magical fiber. Rifles bound with mana-channels to reduce recoil or improve accuracy. Magic Access Rich, regulated, industrialized. They use alchemical reactors to convert mana into power, ammunition, even artificial daylight. Their Main Units Infantrymen Rifles with bayonets and short swords. Standard issue rune shields. Well-trained and fed. Sappers Diggers of death. They carve new labyrinths or strike into enemy tunnels. Close-range fighters with spiked shovels and demolition charges. Otis Jones Commando Group Named after their commander, Jones, a phantom in the tunnels. Silent running boots, short-barrel repeaters, and “shadow cloaks” that bend dim light. Kingsmen Brutal elite troopers. Heavy magical armor that hums. Light machine guns with mana-fed “everbelts” that produce endless ammo until the mana cell burns out. Extra King's Faction Roles

1. Tunnel Artificers Engineer-mages who project hard-light bridges or barriers to stabilize crumbling tunnels. They can weaponize it too.
2. Mirewind Alchemists Creators and controllers of the toxic gas above. They refine it into grenades or defensive fog walls.
3. Palisade Walkers Walking tank suits. Not quite mecha, but towering armored exoskeletons with rotary mana cannons.
4. Cinder Clerics Priests who channel magic into healing or painful flame. Their doctrine praises the King as destiny incarnate.

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THE WORLD ITSELF Infrastructure of the Underwar

1. Spiral Rails Rail lines carved in descending corkscrews. Their trains are armored worms of steel, each car pressurized to keep the gas out. Losing a rail line is like losing half an army’s mobility.
2. Rail-Mounted Siege Cannons “Brontocannons.” Huge mana-fed guns that can collapse entire tunnel networks in one shot.
3. Reservoir Cities Massive underground caverns containing fungal farms, artificial lakes, and ventilation towers. Constantly invaded, sabotaged, or starved.
4. Echo Towers Magical listening posts. They detect enemies through tremors and mana ripples.
5. Burial Rivers Slow streams polluted by centuries of war, glowing faintly from magical runoff. Corpses drift endlessly in them.

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NEW TECHNOLOGIES AND MAGICAL EQUIPMENT

1. Ember Shields Metal plates infused with salamander-essence. Heat up when struck, burning enemy blades.
2. Frost Munitions Bullets that explode into cold fog, freezing moisture in lungs.
3. Heartroot Armor Plant-grown armor used by the Old Empire. Reacts to the wearer’s heartbeat, stiffening during danger and softening during exhaustion.
4. Lantern Bombs Shatter and release swarms of light-sprites that blind, burn, or confuse.
5. Bound Spirits Some tunnels have guardian spirits sealed to serve one side or the other. They glow like ghostly soldiers but are more force than flesh.

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CIVILIANS The true victims. Some have lived their entire lives without seeing the sky. They tell stories about the sun the same way we talk about dragons. They grow mushrooms in soot-gardens. Many have lung scars before age seven. Old Empire civilians risk starvation, collapses, disease. King’s civilians risk oppression, forced conscription, or being “relocated” to deeper sectors. In both nations, entire families disappear in collapses or gas breaches.

THE TONE OF THE WORLD A strange mix of iron, myth, soot, and almost-forgotten magic. A place where rifles fire in pitch-black tunnels and knights wear gas-scarred plate armor. A war where the surface is a shimmering golden graveyard. A world still fighting long after the reason is lost. And everyone whispers the same line: If we ever see the sun again, it will be without us. Sure. Let me drag myself through the rubble and cough up an even bigger world for you. If this thing gets any larger, it’s going to qualify as an ecosystem. But fine. Here we go, icat — a whole universe carved out beneath the dead sky, dripping with magic, metal, and misery. I’ll expand everything: both nations, every faction, the cultures, the technology, the environments, the magic, the history, even the weird creatures that lurk in the gas. Settle in. It’s long. It’s heavy. It’s got that WW1‑but‑enchanted‑and‑medieval vibe you asked for.

THE EXPANDED UNDERWAR REALM A world where history took a wrong turn, fell into the dirt, and kept digging. THE SURFACE: WHAT REMAINS OF EARTH For almost a century, the world above has been drowned in Mirewind, the magically enhanced mustard gas that once drifted like a morning fog and now clings to everything like a cursed sea. The ground gleams yellow and gold where it once was green. Surface Hazards

1. Airstorms Violent swirls of concentrated Mirewind, glowing like auroras. They shred lungs instantly, but they also carry echoes of the souls of the first victims. Wanderers hear voices calling their name.
2. Glass Forests Trees turned to crystalline husks. Their branches ring like chimes when the toxic winds touch them. Sometimes shadows pass through the glass trunks, faceless and silent.
3. Rot Holes Craters where gas pools. A person can fall through and vanish in seconds, dissolved into yellow slurry.
4. Gas-Beasts Mutated animals that adapted. Wolves with translucent flesh. Crows shimmering like fog. Deer that breathe poison.

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THE TUNNEL WORLD Humanity retreated underground, but they didn’t retreat evenly. The tunnels of this world twist into a labyrinth of cultures, factions, and territories. Think of the entire Earth as an anthill with skyscraper-sized caverns.

THE OLD EMPIRE (Expanded) A crumbling titan, too proud to fall, too exhausted to stand. Culture Once aristocratic and ornate. Now a patchwork of soot-stained traditions. Families wear blackened medals of ancestors who died before the sky vanished. Storytellers recite epics of ancient kings but cough through half the stanzas. Children play games pretending to be knights, though their wooden swords splinter under damp air. Government The Empire was once a stratified monarchy. Now the Emperor is a symbol, protected deep underground, surrounded by relics, barely seen by living soldiers. Real power sits with the Council of Iron Lungs, the engineers who control the ventilation systems. If they turn off the air in a district, it collapses within hours. Military Structure They still call their soldiers “legionaries,” though the legions are tiny now. Their gear is a mix of medieval soul and industrial horror: ragged plate armor reinforced with rivets shields lined with old spell-inscriptions spears tipped with re-melted gun barrels rifles so old they spark when fired Special Old Empire Roles (Expanded) Lanternbearers They “listen” to the tunnels through magic vibrations. They sense collapses, enemy digging, or gas seepage. Some go blind early because their senses burn out. Rotwardens The underground is always close to plague. Rotwardens use purifying charms, heat spells, and surgical tools. They’re feared because they torch entire corridors when infection spreads. Ironskalds Their chants aren’t pretty. They’re rhythmic, metallic, almost like industrial music. They fight as they sing, keeping squads steady in panic-filled darkness. Gloom Riders Mounted on huge burrowing reptiles called Deep Drakes, creatures bred to survive heat, pressure, and poison. Gloom Riders strike fast, then vanish into side tunnels. Nightforgers Blacksmiths who work with fungi-fire, a flame that grows colder as it burns. Their armor looks ugly and ancient, but it never breaks. New Elite Unit: The Pale Guard Silent warriors born underground, so pale their skin reflects torchlight. They move almost soundlessly. Armed with halberds made from railway steel.

THE KING’S FACTION (Expanded) Tyrannical. Efficient. Perfectly fed. A society that thrives in war because the King demands it. Culture Citizens live under strict order. Food is rationed but always enough. Electric lights glow in every settlement thanks to mana reactors. Education focuses on loyalty, engineering, and survival. Propaganda posters show the King holding back the fog with one hand and crushing the Empire with the other. Government An absolute monarchy supported by the Mantle Bureau, a bureaucratic organization that monitors ventilation, resources, and public loyalty. They control: food water mana allocation tunnel expansion Military Structure Modernized, disciplined, terrifyingly efficient. Their weapons fuse: steel alchemical cores mana channels crystallized runework Special Units (Expanded) Infantrymen Standard soldiers with rifles and swords. Their rifles shoot mana-stabilized bullets that curve slightly toward heat signatures. Sappers Diggers who fight with saw-blades and explosive rune charges. Many go deaf within five years. Otis Jones Elite infiltration unit. They carry whisper-barrels (guns that make almost no sound). Their commander, Jones, is rumored to see in absolute darkness. Kingsmen Heavy troopers with armor like walking fortresses. Their light machine guns pull ammo from mana “everbelts” that feel disturbingly alive. New Role: Crown Eclipsers Stealth sappers who collapse enemy tunnels using portable gravity runes. New Role: Rift Enchanters Mage-engineers capable of opening temporary rifts to siphon raw mana from the earth. Dangerous work; some evaporate instantly. New Role: Ember Surgeons Combat medics whose healing spells feel like fire in the veins. Soldiers both fear and worship them.

MAGIC SYSTEMS OF BOTH SIDES Magic in this world is geological. It comes from the crust, braided into minerals and fossilized life. Old Empire Magic Unstable. Ritualistic. Fragile. Bone charms Rune stones Chanting magic Blood-binding spells Fungi alchemy Spirit pacts Their magic is like old machinery: temperamental but powerful when maintained. King’s Faction Magic Industrialized and refined. Mana reactors Enchanted circuitry Synthetic crystals Alchemical gas processing Healing flares Light-density manipulation Their magic is predictable, weaponized, mass-produced.

INFRASTRUCTURE Spiral Rails Massive corkscrew-shaped tracks that descend deeper underground with every turn. Trains are armored beasts that can withstand shockwaves. Losing a Spiral Rail is like losing an artery. Rail-Mounted Siege Cannons Titanic cannons on flatbeds. They fire mana-charged shells that induce shock tremors, collapsing tunnels for miles. Reservoir Cities Underground cities built around giant lakes of clean water. They glow with bioluminescent moss and hold: farms markets clinics barracks They’re constantly raided. Echo Towers Thin spiraling towers carved into cavern walls. Using mana resonance, they map movements up to 2 miles away through vibrations. Burial Rivers Underground streams filled with skeletons and glowing rot. Some say they whisper names. Ventilation Cathedrals Huge chambers filled with spinning rune fans. Repairs require mages, mechanics, and courage.

CREATURES OF THE DEPTHS The underground gave birth to horrors: Blind Basilisks Huge serpents with heat detection senses. Their breath causes hallucinations. Cinder Moths Winged insects leaving trails of burning dust. Used as living bombs. Grave Crawlers Half-human things, mutated from soldiers trapped in collapses. Drill Hounds King-bred attack beasts with metal-tipped snouts and reinforced spines. Glow Rats Common. Bioluminescent. A delicacy.

THE HISTORY OF THE WAR The First Gasfall (1928) A magical experiment misfired. Mirewind spilled into the sky. Cities died in hours. The Burrowing Rush (1930–1940) Humanity dug downward. The King consolidated power. The Old Empire fractured but endured. The Great Collapse (1955) A tunnel catastrophe killed 200,000. The King blamed the Empire. The Empire blamed sabotage. Age of the Worm Guns (1970–1990) Gigantic rail guns capable of leveling caverns. Neither side gained ground. Century Mark (2014) No sunlight for 86 years. No end in sight.