The Drowned Sewer

Beneath the streets, the drowned still tend their endless watch.

4 roomssewermedium

Beneath the oldest streets lies a forgotten sewer shrine where drowned corpses refuse to remain dead. The tunnels are small but treacherous, and every chamber bears signs that the dead are gathering around a single hidden master.

Cold, knee-deep runoff winds through cramped brick channels. The air reeks of stagnant water, lamp oil, and old bones, while dim green light leaks from patches of corpse-moss along the walls. Every splash echoes too long, and distant knocking sometimes answers the party's footsteps.

☠ Threat

The Drowned Caretaker, a former plague priest, has awakened as a shambling undead custodian. It commands the corpses washed into the sewer and seeks to break the last ward beneath its shrine. If left undisturbed, it will flood the lower streets with corpse-tainted water and raise the recently dead throughout the neighborhood.

History

A century ago, the city buried plague victims in a pit beyond its walls. When the district expanded, masons built a sewer over the graves and placed a small shrine at the lowest junction. The shrine's priest sealed the dead beneath it with blessed iron charms, but later workers broke the seals while widening the channels. The first drowned caretaker rose and made the tunnels its crypt.

Encounter Table

CR
1/8CR
Lantern Deadx1

A waterlogged corpse with a broken lantern shuffles through the channels, following sounds and light.

1/4CR
Bone-Ridden Rat Swarmx1 swarm

A cluster of pale rats swarms over a half-sunken skeleton, whose hands still twitch as if trying to crawl free.

1/8CR
Dead Maintenance Crewx2-3

Three drowned workers drag a chained toolbox through the water. They ignore the living until someone blocks their route toward room-1.

Rumours & Whispers

1

A watch patrol entered the old sewer last week and returned with one man missing and all its lanterns extinguished.

2

People who drink from the south fountain hear knocking beneath their homes at night.

3

A dead priest walks below the streets and collects the names of everyone who has recently died.

4

The sewer contains a forgotten chamber where plague victims were sealed with silver and jewels.

Quest Hooks

1
Voices in the DrainRescue

Quest giver: Mara Venn, a frantic laundress whose youngest child is missing

Several children have vanished near a storm drain, and witnesses heard them calling from beneath the street after midnight.

25 gp, free lodging for a week, and a silver family locket

2
Proof of the DeadInvestigation

Quest giver: Sergeant Pell, an exhausted watch officer

The city watch wants proof that the sewer deaths are supernatural before it authorizes an expensive purge.

A formal writ allowing the party to claim recovered valuables and a healing potion

3
The Missing CharmsRelic Recovery

Quest giver: Sister Halwen of the Lantern Chapel

A temple's warding charms have been stolen and carried into the sewer, where they are being used to strengthen the undead shrine.

A blessed torch that burns underwater for 1 hour and 30 gp

Corridor Notes

Between Room 1 and Room 3

Black water trickles through shallow side channels, carrying teeth, buttons, and scraps of burial cloth toward the lower rooms.

Outside Room 2

Rusty maintenance ladders climb into sealed shafts overhead. Something has recently dragged muddy fingers down several rungs.

Between Room 1 and Room 4

Small clay charms shaped like skulls hang from iron hooks. Most are cracked, but one turns to face anyone carrying a lit torch.

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