The Drowned Ledger

The old light works now drown in black water, and something below waits for the town's lamps to fail.

7 roomsDeep dungeon that goes to the underdark. The party is locating and escorting a supplier who has yet to return back with supplies to make important enchanted oil and wicks for lanterns that are designed to keep beasts off the streets at night. Without this supplier and supplies, less light for the town spells certain disaster for its citizens. medium

Beneath the ruined town supply works lies a flooded distribution hall that once stored lamp oil, enchanted wicks, and delivery ledgers for a network meant to keep the streets lit and beasts at bay. Now the lower level has become a choke point of knee-deep water, unstable catwalks, and predatory intruders, with the missing supplier somewhere below and signs that a deeper faction has seized the dark.

Cold water ankle to knee deep, oil-slick and stale, fills the lower halls with a sharp scent of rust, mildew, and old lantern tallow. Drips echo from cracked stone while distant channels groan behind the walls, and the light from carried lanterns turns the floodwater into moving black glass.

☠ Threat

A subterranean faction of cave-dwelling raiders and corrupted tunnel servants has claimed the lower cisterns, using the flood choke point to control access while they stockpile stolen lantern oil and intercept anyone who comes looking for the missing supplier. Their leader keeps the supplier alive for guidance and leverage, and is preparing to sabotage the town's light network by tainting or withholding the remaining enchanted materials.

History

This complex was built decades ago as part of a town supply works, where enchanted oil, wax, and treated wicks were stored before being carted to street lanterns and watch beacons. When the first floodgate cracked, workers sealed the lower hall to save the surface stores, but the failure spread through the cisterns and left the deepest chambers abandoned until something from below moved in.

Encounter Table

CR
1/2CR
Giant Ratsx1d4

Thin scavengers that slip between broken crates and attack anything carrying food or light.

1CR
Goblin Flood-Runnerx1d3

Small raiders wearing oil-skin scraps and using stolen tools as weapons.

2CR
Hobgoblin Patrolx1d2

Disciplined tunnel soldiers patrolling between choke points with polearms and whistles.

3CR
Duergar Enforcerx1

A grim labor brute carrying hooks, chains, and a lantern cage full of bones.

Rumours & Whispers

1

The supplier vanished after taking a cartload of oil and wicks to the old works, but the gatekeepers swear they heard singing from below.

2

People say the lower cistern floods on its own whenever torches are lit near the west drain.

3

A clerk in town claims the missing ledgers were altered before the delivery team left, as if someone expected them not to return.

4

Old miners warn that the drainage tunnels open into deeper caves where pale folk trade in stolen light.

5

A broken lantern recovered near the works had black fungus growing inside the glass, though it had never been filled with anything wet.

Quest Hooks

1
The Last DeliveryRescue

Quest giver: Captain Elra Venn, town watch captain

The town's night watch hires the party to find the missing supplier and recover enough oil and wicks to keep the wards burning through the next moonless stretch.

350 gp and a case of enchanted lantern oil

2
Missing from the LedgerInvestigation

Quest giver: Mira Tallow, counting-house clerk

A desperate clerk offers a hidden map of the old supply works if the party brings back the ledgers that prove who diverted the last shipment.

200 gp and access to sealed records

3
Dark Between the LampsDefense

Quest giver: Borin Vale, apothecary and lamp-maker

Strange beasts have begun testing the streets at night where lanterns have gone dim, and the party is asked to stop the source before the wards fail completely.

A batch of superior oil and a favor from the craft guild

Corridor Notes

Between Room 2 and Room 5

Riveted pipework runs along the walls, still carrying occasional cold surges that rattle the grates.

Between Room 3 and Room 4

Collapsed freight rails jut from the floor, half-buried under silt and broken crates stamped with lantern marks.

Between Room 5 and Room 8

A narrow drainage slit leaks warm air from the deeper chambers, carrying faint voices in Undercommon.

Near Room 6 and Room 7

Chains and rusted pulley hooks hang over the corridor junctions, left to lift oil barrels that no longer exist.

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