The Bile-Duct Oubliette

The city's waste hides a rotting secret that breathes in the dark.

15 roomssewermedium

A sprawling network of forgotten subterranean channels where the city's filth congeals into malevolent life. It is a place of heavy humidity, slick stone, and the constant echo of dripping sludge.

The air is thick with a sulfurous stench and the sound of gurgling liquid. Dim greenish bioluminescence from toxic algae provides the only light, and the temperature is uncomfortably warm and humid.

☠ Threat

A massive, sentient mass of acidic sludge known as The Great Slime-Father is slowly dissolving the foundations of the city above to feed its growth. Its influence mutates the local vermin and animates the very waste that flows through the pipes.

History

Built by the Gutter-King Malakor a century ago, these sewers were designed to bypass the city's main drainage for illegal smuggling. After an experiment with necrotic waste went wrong, the entire sector was sealed off and erased from official maps to hide the disaster.

Encounter Table

CR
5CR
Sludge Drifterx1d4

Floating balloons of gas and acidic jelly that explode on contact.

8CR
Sewer Crocodilesx2

Massive reptiles mutated by the toxic runoff, featuring chitinous plates.

6CR
Flesh-Eating Swarmx1

A carpet of thousands of oily, aggressive centipedes.

Rumours & Whispers

1

The city council is paying a fortune for anyone who can stop the sinkholes appearing in the market district.

2

They say the Gutter-King didn't die; he just became something much more fluid.

3

A strange, greenish glow has been seen emanating from the storm drains at midnight.

4

Avoid the pipes that hiss; the steam carries a rot that can melt the skin off your bones.

Quest Hooks

1
The Sinking PlazaUrgent

Quest giver: Lord Mayor Hallowell

The main city plaza is slowly sinking into the ground. The characters are hired to find the cause and stop it.

10,000 gold and a plot of land in the city.

2
The Lost HeirloomPersonal

Quest giver: Lady Elara

A noble's daughter dropped a priceless signet ring down a drain. She believes it has been swept into the Bile-Duct.

A rare magic item from her family's collection.

Corridor Notes

Between Room 2 and Room 5

A series of rusted pipes that groan and shake as if something massive is moving inside them.

Between Room 3 and Room 12

The walls are covered in a thick, slick moss that smells faintly of peppermint and decay.

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