A1-S2 — The Descent to the Sinkhole

From Bridge to River Level · Two‑Stage Descent

Stage 1 — The Town‑Assisted Rope Descent (200 ft)

The town engineers lower the party down the official rope route. The descent plummets 200 feet through mist and spray, ending at a narrow platform at the base of the bridge's eastern pillar. From there, the party must continue on foot.

The ropes creak and sway as you descend into the abyss. The bridge above vanishes into fog, and the roar of the Noyrus becomes a physical force — a constant, thunderous pressure against your ears. Mist clings to your clothes, and the cold seeps through your gear. After what feels like an eternity, your boots find solid rock: a narrow platform at the base of the pillar, slick with spray. Below, the river churns and crashes against a narrow, rocky shore.

Stage 2 — The Metal Rungs (50 ft descent)

From the pillar base, a series of U-shaped metal rungs — each bent into a rough staple — have been driven into the rock face. They descend 50 feet down the steep cliff to the river's edge. The rungs are corroded, slick with spray, and worn smooth by years of use. The party may choose to clip together with safety ropes for mutual support, or descend individually.

Below the pillar, the rock face plunges toward the river. Iron rungs — some rusted, some bent — cling to the stone like the ribs of a long‑dead beast. The descent is slow and treacherous. Fifty feet below, the river crashes against a narrow shore of jagged rocks. The water is dark, fast, and cold; spray rises in curtains, drenching everything. The cliff walls on either side rise nearly vertical, composed of dark metamorphic and igneous stone — schist and basalt, slick with moss and algae. To your left, a massive chunk of the rock face has been carved away at river level — a dark, gaping wound. Water from a side eddy rushes into it, vanishing into the earth. That is the sinkhole.

Safety First: The party may choose to clip together using climbing ropes. If clipped, each character gains a +2 circumstance bonus to Climb checks, but they move at half speed and must stay within 10 ft of each other. If one falls, the others can attempt a Strength check (DC 15) to arrest the fall, preventing injury.

Terrain and Checks — The 50‑ft Rung Descent

Descending the metal rungs requires a series of Climb checks. Each 10‑ft section of the descent is a separate check. The rungs are very slippery due to spray, algae, and corrosion.

Section	Check	Success	Failure / Fumble
Upper rungs (10 ft)	Climb DC 10	Descend 10 ft safely.	Slip and slide 5 ft down; take 1d4 nonlethal damage from scrapes. If clipped, the rope catches them (no damage, but they lose 1 action).
Mid‑upper rungs (10 ft)	Climb DC 12 (slippery)	Descend 10 ft safely.	Lose grip; slide 10 ft; DC 15 Reflex or fall prone on the next landing. If clipped, the rope holds but jerks the whole group — everyone must make a Climb check to maintain their grip.
Mid‑lower rungs (10 ft)	Climb DC 14 (very slick, spray)	Descend 10 ft safely.	Fall 10 ft; take 1d6 damage, land prone on a narrow ledge. If clipped, the rope arrest check is DC 18.
Lower rungs (10 ft)	Climb DC 16 (corroded, wet, near water)	Descend 10 ft safely.	Fall the remaining distance (up to 10 ft) — take 1d6 damage, land in shallow water (prone). If clipped, the rope arrest check is DC 20.
Final rungs (10 ft)	Climb DC 14 (near shore, waves)	Reach the rocky shore safely.	Slip and slide into the river — DC 14 Swim to avoid being swept downstream.

GM Tip — Clipping Together: The party can decide to clip together for safety. Doing so imposes a –10 ft speed penalty on the descent (each 10‑ft section takes 2 actions instead of 1), but grants a +2 circumstance bonus to all Climb checks and allows the group to arrest a fall with a collective Strength check (DC 15). If a character is not clipped, they descend faster but risk a more dangerous fall.

Options and Alternatives

Approach	Effect
Clip together (group)	+2 Climb, half speed, fall arrest possible (Strength DC 15). If one slips, the rope jerks the group — all must make a Climb check (DC 12) to hold on.
Descend individually	Full speed, no fall arrest. Each character makes their own Climb checks. If they fall, they take damage and land in the water or on the rocks.
Use magic	Spider climb or Fly negates the need for checks entirely. Feather fall negates fall damage if a character slips.
Drop a knotted rope	If the party has a knotted rope, they can lower it over the rungs. Climb DC drops to 8, and falling is prevented if they are tied in.

Example Descent (Group Clipped): The party clips together in a line. They move at half speed, so the 50‑ft descent takes 10 rounds (5 ft per round). Each character makes Climb checks DC 10, 12, 14, 16, 14. On the fourth section, the rogue slips — the group Strength check (DC 15) passes, and the fall is arrested. They take 1 round to recover, then continue. They reach the shore safely, but slightly bruised and with a lost round.

Reward for Caution: If the party clips together and successfully descends without incident, they gain a +1 circumstance bonus on their first Perception check to spot the ambush (Encounter 1), as they arrive quietly and together. If they descend individually and someone falls, the noise alerts the defenders, imposing a –2 penalty on the party's initiative.

At River Level — The Shore and Sinkhole

After the 50‑ft descent, the party reaches the river's edge — a narrow, rocky shore of broken basalt and schist, barely wide enough for two people to stand abreast. The Noyrus roars past, dark and swift, only a few feet away. The cliffs on both sides rise nearly vertical, composed of metamorphic and igneous rock — slick, jagged, and unforgiving. The shore is littered with driftwood, smooth stones, and the occasional rusted tool.

To one side, a massive chunk of the rock face has been carved out at river level — a dark, gaping wound in the stone. This is the sinkhole. Water from a side eddy rushes into the opening, creating a roaring curtain of spray. The sinkhole mouth is roughly 15 feet wide and 10 feet high, and the water disappears into darkness. Fresh boot prints and tool marks lead from the shore into the opening.

Immediate Observations

Visibility: Dim light from the surface; torches or darkvision required beyond the sinkhole mouth.
Noise: The waterfall roar and river sound impose a –2 penalty on Perception checks to hear anything beyond 20 ft.
Footprints: Fresh boot prints and tool marks lead from the shore into the sinkhole — evidence of recent activity.
Obsidian Chips: Small flakes of black volcanic glass are scattered near the sinkhole edge.
Scraped Trail: Goods have been dragged from the shore into the sinkhole.
Ancient Masonry: The carved edges of the sinkhole show tool marks — this is not a natural formation.

GM Note: The sinkhole is the entrance to the lair. A1‑S4 (First Watch Patrol) begins once the party moves past the sinkhole mouth. The party's approach method (clipped or individual) affects their initiative and surprise round.

TODO: Expand the sinkhole interior description and prepare the encounter trigger for A1‑S4.

Map 1 — River Shelf and Sinkhole Lip (Top‑Down View)

This map is oriented with the bridge spanning from north to south (top to bottom) across the Noyrus River, which flows east to west (left to right). The fixed ropes descend from the bridge to the slippery shelf.

NORTH | | Bridge Roadway Above ================================ Ancient black-stone arches lost in fog ================================ Bridge Pillar ################ # # # # # [A] Rope # # Descent # # # ################ || || Fixed town ropes || Cliff wall || Slippery shelf ########### || ################ # # || # # # # || # River edge # # [C] #====# # # scraped # || # [D] ancient# # trail # || # masonry # ########### || ################ || || ←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←← ← Main Noyrus Flow (east to west) ← ←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←←← || || Side Eddy ~~~~~~~ ~~~~~ ~~~ [B] Sinkhole Lip ~~ ___________________ ~~~> / \ / water drains down \ / into broken opening \ /_________________________\ [A] Rope Descent — official town‑rigged ropes to river level [B] Sinkhole Lip — where water and debris vanish into the darkness [C] Scraped Trail Marks — signs of recent smuggler activity [D] Ancient Masonry Exposed — cyclopean stonework, not natural

GM Note: The bridge spans from north to south; the river flows east to west. The sinkhole lies on the southern bank, near the western edge of the bridge's shadow. The fixed ropes descend from the bridge's eastern pillar to the slippery shelf on the south side. The scraped trail leads from the shelf toward the sinkhole lip.

Key Features

Feature	Description
Bridge	Spans north–south (top to bottom), 400 ft across the river, 120 ft above the water
Noyrus River	Flows east–west (left to right), cold and fast-moving
Sinkhole	Located on the south bank, near the western edge of the bridge's shadow
Rope Descent [A]	Fixed ropes from bridge pillar down to river-level shelf
Scraped Trail [C]	Smuggler activity — leads from shelf toward sinkhole
Ancient Masonry [D]	Cyclopean stonework exposed in the cliff face — not natural

Terrain Warning: The shelf is slippery and uneven. Characters moving faster than half speed must succeed at an Acrobatics check (DC 11) or fall prone. The side eddy near the sinkhole lip can pull characters toward the opening — any character entering the water must succeed at a Swim check (DC 12) or be dragged 10 ft. toward the sinkhole.

A1-S2 — The River-Level Descent

Premise

If the party chooses the town‑assisted rope descent, engineers lower them down the official route. The descent reaches a slippery shelf near river level, where the party must scramble across wet rocks while clipped into safety ropes. The Noyrus River itself does not pour directly into the sinkhole. Instead, the sinkhole sits off to one side of the river, where a side eddy once curled back into the main flow. Now that side current drains into the sinkhole opening.

The roar of the Noyrus grows until speech becomes gesture. Mist beads on armor and hair. Below the bridge, slick basalt shelves angle toward the river, and the fixed town ropes sway in the spray. To one side, where the current should curl back into the river, the water now vanishes into a dark, broken wound in the stone.

Skill Checks — The Descent

Reaching the sinkhole lip requires a series of skill checks. The party is clipped to safety ropes for most of the descent, so failure usually means a delay, a lost item, or a minor injury rather than an immediate death.

Obstacle	Suggested Check	Failure Consequence	Success Benefit
Slick river shelf	Acrobatics DC 11 or Reflex DC 12	Fall prone or slide 5–10 ft. while clipped to rope; lose 1 action on next turn.	Maintain footing and move freely along the shelf.
Rope‑supported traverse	Climb DC 10	Lose 5 ft. of movement; gear may scrape loose — one item falls into a shallow pool (recoverable).	Cross the traverse without incident.
Spray and noise	Perception DC 12 (with a –2 penalty due to spray)	Miss signs of recent activity (scout tracks, tool marks, or the kobold alarm runner).	Spot fresh footprints, obsidian chips, or movement near the sinkhole lip.
Cold side eddy	Swim DC 12 if the character falls or enters the water	Dragged 10 ft. toward the sinkhole lip; take 1d4 cold damage from the frigid water.	Swim back to the shelf or grab a rope without losing position.
Ancient masonry exposure	Knowledge (Engineering) DC 13 or Perception DC 14	Fail to notice that the stonework is not natural — the sinkhole was excavated, not formed by erosion.	Identify tool marks, chisel grooves, and recent reinforcement timbers, confirming intelligent activity.

GM Tip: Encourage creative solutions. A character with rope‑tying proficiency (or a relevant background) can secure the traverse for the rest of the party, granting a +2 circumstance bonus to everyone's Climb checks. Likewise, a character who succeeds on the Perception check can warn the party about the kobold alarm runner before Encounter 1 begins, potentially granting a surprise round.

Group Check Option

If the entire party is descending together, you may allow a group check for the Acrobatics and Climb portions. At least half the party must succeed for the group to progress without incident. If the group fails, the party arrives at the bottom disorganised — each character who failed their individual check takes a –1 status penalty to initiative for the first combat encounter.

Key NPCs (Present at the Descent)

NPC	Role	What They Want
Rigger Heskel Vane	Rope master & pulley operator	Wants to ensure the party is securely clipped and that no equipment is lost.
Apprentice Lira Toll	Engineer’s assistant	Wants to take notes on the lower pillars; scared but curious.
Guard Miro Kael	Bridge watchman	Wants to confirm the sinkhole isn't a threat to the bridge's foundation; will report back to the Tollmaster.

TODO: Add optional hero points for creative skill use (e.g., using a shield as a sled, tying off ropes with a clever knot, or using magic to calm the water). Consider adding a "critical success" column to the skill table for extra rewards.