The Sub-Terranean Sump

A tomb of rust and chemicals where the Great War never ended.

8 roomsFirst Great War. Trenches, artillery, forts against forts. Grim. Realism. Regions turned between imperial cult of ruthless warmongering Kaiser, freedom seeking disillusioned leader of insurgency and rivalrous country that funding rebels and cause uprising in proxy war. Conspiracies, subterfuge, espionage and experimental armaments. All weapons is deadly if hit without heavy protection, cover or disadvange against enemy.medium

A claustrophobic labyrinth where ancient stone sewers meet the jagged, mud-caked tunnels of modern sappers. The atmosphere is thick with toxic fumes and the rhythmic thud of surface artillery that shakes the very foundations of the city above.

The air is cold and smells of sulfur, stagnant water, and machine oil. Distant iron grinding and muffled explosions provide a constant auditory backdrop. Lighting is limited to infrequent gas lamps that hiss and flicker with a sickly yellow glow.

☠ Threat

Major Hasso Von Zale leads a contingent of Kaiser-loyalist deserters known as the Iron Rats. He has rigged the Sump with experimental chemical explosives and stolen enough heavy artillery components to level the entire administrative district above. His goal is to provoke a total collapse of the ceasefire by framing the insurgency for a devastating surface-side explosion.

History

Originally built to handle the runoff of Ironwright's Block, these tunnels were repurposed by the Kaiser's engineering corps during the Siege. When the front lines stalled, it became a subterranean battlefield for sappers, miners, and counter-miners. Today, it serves as a lawless artery for rogue soldiers and weapon smugglers who move illicit artillery components beneath the feet of the Imperial occupation.

Encounter Table

CR
1CR
Sapper Patrolx2 soldiers

Tired soldiers carrying lanterns and repeating crossbows.

1/2CR
Chemical Leakx1

A cloud of yellow chlorine gas that drifts through the hallway dealing poison damage per turn.

1/4CR
Giant Sewer Centipedex3

Mutation-warped insects that can paralysis targets with a sting.

Rumours & Whispers

1

A rogue officer has been seen buying huge quantities of magnesium and sulfur at the black market.

2

People living above the Sump complain of a strange, rhythmic metallic hammering coming from their floorboards.

3

The sewers near Ironwright's Block have turned a vivid shade of neon green and the fish are dying.

4

A rebel courier disappeared in the Sump while carrying blueprints for the new Imperial breech-block.

5

The Iron Rats aren't deserters, they are a secret branch of the Kaiser's own secret police.

Quest Hooks

1
The Stolen Breech-BlocksRecovery

Quest giver: Elias Thorne, Resistance Leader

The local resistance group needs someone to recover the stolen artillery parts before they are used against the city.

200 gp and a promise of safe passage.

2
Silence the MajorAssassination

Quest giver: The Cloaked Contact

An anonymous donor from the rival country wants Von Zale removed to prevent the explosion he has planned.

500 gp and a high-quality masterwork weapon.

Corridor Notes

Connecting room 1 and 3

Piles of rusted brass shell casings from a previous skirmish.

Before room 7

A heavy iron door that requires a specific code found on a guard's corpse.

Outside room 2

A puddle of slippery oil that requires a DC 12 Dexterity save to avoid falling.

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