The Drowning Gate
A massive, soot-stained iron portcullis set into a deep stone archway along Leidon's southern wall. This gate regulates the flow of the city's waste and storm runoff into the surrounding marshes. During heavy rains, the gate is lowered deep into the muck of the central sewer channel to prevent backflow and keep intruders from swimming into the city. The iron bars are unusually thick and etched with primitive, rusted sigils that hum with a faint, low-frequency vibration when the tide is high.

The Drowning Gate
The air is heavy with the smell of stagnant water and old iron. The sound of rushing water echoes off the vaulted stone ceilings, creating a constant, rhythmic drumming that makes quiet conversation difficult. It feels claustrophobic and damp, as if the weight of the city above is pressing down into the mud.
A massive, soot-stained iron portcullis set into a deep stone archway along Leidon's southern wall. This gate regulates the flow of the city's waste and storm runoff into the surrounding marshes. During heavy rains, the gate is lowered deep into the muck of the central sewer channel to prevent backflow and keep intruders from swimming into the city. The iron bars are unusually thick and etched with primitive, rusted sigils that hum with a faint, low-frequency vibration when the tide is high.
A man of fraying nerves and meticulous habits. He is obsessed with checking the tension on the gate cables and is constantly worried that the city council will cut his maintenance budget.
History
Maintenance Logistics
Operating the gate requires a team of four laborers working the primary winches in unison. Because of the constant exposure to sewage and moisture, the chains must be greased with rendered fat every three days to prevent the mechanism from seizing entirely during a flood.
The Drowning Mechanism
The gate is designed with a failsafe. If the city is breached from the south, a secondary lever can be pulled to collapse a segment of the overhead spillway. This intentionally floods the immediate gatehouse area and the primary sewer tunnel with ten feet of water, effectively drowning any attackers trapped in the bottleneck.
Subterranean Security
Two elite guards, known as the Drain-Watch, are stationed in the upper room of the gatehouse. They are equipped with long reach polearms and heavy crossbows with barbed bolts, specifically designed to pin aquatic threats against the iron bars of the portcullis.
Denizens
A man of fraying nerves and meticulous habits. He is obsessed with checking the tension on the gate cables and is constantly worried that the city council will cut his maintenance budget.
A wiry man who has spent twenty years navigating the sewers. He knows every tunnel and pipe leading to the gate and has lost three fingers to various 'sewer nibblers'.
A priestess who spends her days cleaning the moss from the sigils. She claims the gate can hear the city breathing and warns that the rust is a sign of the gate's growing hunger.
Rumors & Plot Hooks
- 1.The sigils on the gate were not meant to keep water out, but to keep a specific entity trapped beneath the city.
- 2.Small objects made of silver often wash up near the gate's base after a heavy storm.
- 3.One of the night guards claims he saw the rusted sigils glow a sickly violet when the moon was full.
Classified Entry
The rusted sigils are a series of Glyph of Warding and Hold Monster spells designed to trigger if a Gargantuan creature attempts to pass through the channel. The 'rust' is actually dried, magical residue from a blood sacrifice performed decades ago to empower the wards.
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