The Drowned Ledger

RoomPuzzle Room3 exits

floodedpuzzle-logiclore-checkdrowning

Illustration: Room 14 — The Drowned Ledger

Water to the chest, and cold enough to make you swear. It is clear water; you can see your own boots on the flagstones, and you can see that the flagstones are ruled in a grid, and that the grid is the footings of shelves.

Ninety pigeonholes, in nine ranks of ten, standing in the flood. The papyrus in them is grey pulp. The clay is fine. And here and there, floating on their backs like little boats, are wax tablets — perfectly, insultingly dry inside their wooden covers.

Three doors in the far wall. Someone cut a mark into the jamb of each one.

DM summary. A records office that flooded a century ago and kept its records. Three doors, three marks, and a ledger that says which of them was re-hung, which was bricked, and which one is holding back a river.

Terrain & Features

Battle-map thumbnail: The Chequered Rooms

Battle map: The Chequered Rooms — page 23, 55 × 75 ft (one half of The Tiled Halls)

Take a 40 × 30 ft room of the chequered suite, shade the whole floor as chest-deep water, and draw the nine ranks of pigeonhole shelves standing in it. The tile grid keeps the shelf rows straight.

Dimensions. 40 ft × 30 ft, ceiling 12 ft, flooded to 4½ feet — chest height on most people, chin height on a few, and you should ask.
Light. None. Whatever the party brought, held above water, throwing a moving net of reflections on the ceiling that makes reading anything harder.
The cold. This is undercroft water and it does not warm up. Every ten minutes in it, Constitution save DC 12 or one level of exhaustion. Say the ten-minute mark out loud each time it passes; the clock is the room's only pressure and it has to be audible.
The shelves. Nine ranks of ten pigeonholes, stone, standing in the water to 9 ft. The lower four ranks are submerged; the upper five are dry and mostly empty, because someone came through here and took what mattered.
The tablets. Wax diptychs in hinged wooden covers. Wax does not care about water. Forty-one of them survive, scattered across the flooded ranks, and every one has a year cut into its cover.
The three doors. West wall, identical, swollen shut, each with a mason's mark on the jamb at knee height under the water: a bull, a wave, and a double-axe.
The high-water line. A brown stain on the wall at 7 ft — a foot above the current level and a foot below the ceiling of the corridor the party came in by. Somebody's river gets higher than this.

Traps / Puzzles / Checks

The puzzle. One of the three doors opens on a corridor. One is bricked up solid behind the timber. One is not a door at all — it is a sluice, and the thing on the other side of it is the undercroft river.

The ledger says which is which. It is a maintenance record and it is ordered by year.

Element	Value
Finding the marks	Perception DC 12, or free for anyone who ducks under and looks at the jambs. They are cut deep and they are meant to be read
Searching the pigeonholes at random	Investigation DC 14 per attempt, 5 minutes each. On a success you surface with one relevant tablet
Searching them properly	History DC 13 or Investigation DC 15: the ranks are ordered by year, left to right, oldest at the north wall. Go to the right rank and take one attempt with advantage
Reading a tablet	No check. It is a clerk's hand and it is very clear
Mechanical fallback	Open them and find out. The bull door is bricked: 10 minutes and Athletics DC 15 with a bar tells you so. The labrys door is swollen and opens to a shove. The wave door — see below
Solved state	The labrys door named, opened, and the party dry-shod within two minutes

What the ledger says, once the party has the right three tablets:

Year nine. Labrys gate re-hung, new pintles, sound. Year eleven. Bull gate bricked to the arch, on the surveyor's word. Year eleven. Wave gate is not a gate. Do not open the wave gate.

Opening the wave gate. It is a sluice against the undercroft river and it opens outward under about nine tons of water. Anyone hauling on it gets one round of warning — the timber flexes, the water in the room moves toward the door, and a fine spray comes through the seams. Say that out loud and let them take their hand off it. If it opens: the room fills at 1 ft per round to the ceiling in eight rounds and cannot be shut against the pressure (Athletics DC 18, and one attempt). The party is not trapped — the stair, exit A, is right there and it goes up — but everything loose in the room is gone within a minute and so is any chance of reading anything.

Exits

AObviousThe half-submerged stair in the north-east corner, going up five treads to a dry landing and an open door. No check, and it stays available no matter how badly the rest of the room goes.Rider: you leave soaked to the chest and cold with it — disadvantage on Stealth for one room, and Constitution save DC 11 on arrival or one level of exhaustion unless you spend ten minutes drying off, which you may not have.

BConditionalThe labrys door, once it is named and shoved.Rider: you leave with a wax diptych in your pack, dry inside its covers after a century in a flood. It is a Sign-tier clue for X14, and the year-eleven entries read as a counterweight and maintenance schedule for X19.

CHiddenThe wave gate, recognised for what it is before it is hauled on. Investigation DC 15, or free from the ledger. Opened deliberately, with the party braced and roped, it is a chute: the room's water goes out through it and takes the party with it, fast, into the undercroft.Rider: Athletics DC 13 or 2d10 bludgeoning off the channel walls; everything not sealed is soaked and one item of the player's choosing is lost. You arrive downstream having personally seen the river, which is an automatic Proof- tier clue for X11.

Loot

None. The valuables went out with whoever emptied the top five ranks, and the coin box under the clerk's stool is a coin box full of silt. The forty-one surviving tablets are worth something to a scholar and nothing at all down here — except the two or three that name a door, which are worth the whole room.

Scaling — APL 6 / 12 / 15

APL	Adjustment
6	Water to the waist, not the chest, and the cold clock runs every twenty minutes. The marks are cut above the waterline. All DCs −2
9	As written
12	Water to the chin — swimming for anyone under 5 ft 6, and everything is done one-handed. The cold clock runs every five minutes. DCs +1, and the wave gate's seams are already weeping, so it opens on its own at the end of the twelfth round in the room
15	As APL 12, and four ranks of shelving have collapsed into a submerged maze of stone that must be swum through: Athletics DC 17 to reach the north ranks at all, and a failure means being briefly pinned. DCs +3

DM Notes

Pacing: 12–15 minutes, hard cap 20. The cold clock is your pacing tool — use it. Two exhaustion levels is the point at which a sensible party leaves with what they have.
If you are behind schedule, the right tablet is floating against the labrys door when they walk in. Read it out. Four minutes, and they still get the clue.
Do not hide the doors. All three are visible from the entry. The puzzle is which, never where, and a party that never solves it can still take the stair.
The wave gate is a real choice and it should be presented as one. A party that reads "do not open the wave gate" and then opens it on purpose, roped and braced, has done something magnificent and should get the clue and the ride, not a punishment. The warning round exists so the decision is informed.
Table safety. Cold water to the chest in the dark, with a stated risk of the room filling, sits directly on drowning. The escape stair is always open and you should show it before anything else. If submersion is a hard no, run the room at ankle depth with the flood risk intact — everything still works, and only the exhaustion clock changes register from cold to fear.
Clue drip. Two hooks: the high-water line at 7 ft, which is above the current level and therefore a promise (X11, X16), and the year-eleven tablets, which are a maintenance ledger for the maze's gates and doors and are the single most useful piece of paper in this stretch of the deck (X19, X08, X14). If your Resolution is X14, note that the ledger's ordering system — ranks by year, holes by month — is itself a lesson in how to make a map of a place that refuses to be mapped.