Beneath the Razored Labyrinth
Pathfinder adventure framework for six PCs · Levels 1-12 · Enda, the Castrovin Sea, Casmaron
Beneath the Razored Labyrinth
Player-Safe Campaign Overview
The Castrovin Sea is vast, storm-scoured, and treacherous. Most sailors hug the coastline, avoiding the deeper waters and the jagged volcanic maze known as the Razored Labyrinth.
Inland, the ancient Bridge of Kridorfrost stands as the only crossing of the Noyrus River for a hundred miles. The bridge-town of Kridorfrost lives by tolls, timber, and river trade.
Then a sinkhole opens beneath the bridge’s lower supports. Workers vanish. Flooded tunnels appear where none should be. Strange black fragments are found in the rubble.
Act 1 Beginning
The heroes begin in or near Kridorfrost during the first wave of the crisis. The immediate problems are practical and urgent:
- Rescue missing bridge workers.
- Stabilize damaged supports.
- Investigate the sudden sinkhole.
- Explore newly exposed flooded tunnels.
- Identify who has been using hidden spaces beneath the bridge.
| Starting Location | Visible Problem | Player-Facing Mystery |
|---|---|---|
| Kridorfrost Bridge | Sinkhole under the lower supports | Why did the bridge fail now? |
| Flooded Tunnels | Missing workers and unstable passages | Who used these tunnels before the collapse? |
| Bridge-Town | Fear, rumors, trade disruption | Who benefits if Kridorfrost falls? |
Campaign Structure — Player View
| Act | Player-Safe Title | Visible Focus | Status |
|---|---|---|---|
| Act 1 | The Sinkhole Beneath Kridorfrost | Bridge crisis, rescue, tunnels, early investigation | Visible |
| Act 2 | Beyond Kridorfrost | To be discovered in play | Locked |
| Act 3 | Across the Castrovin Sea | To be discovered in play | Locked |
| Act 4 | Beneath the Razored Labyrinth | To be discovered in play | Locked |
Opening Objectives
- Reach the collapse site.
- Calm frightened townsfolk.
- Help with rescue operations.
- Enter the exposed lower works.
- Find signs of what caused the collapse.
Early Clues
| Clue | What Players Can Learn |
|---|---|
| Black glassy fragments | The stone does not match local bridge material. |
| Cut support beams | Some damage may have been deliberate. |
| Old tunnel masonry | The bridge may have been built over older structures. |
| Missing tools and rope marks | Someone used these spaces recently. |
Suggested Character Hooks
| Character Concept | Player-Facing Hook |
|---|---|
| Auren Voss | Knows smugglers, dock codes, and the kind of people who hide things under bridges. |
| Nemeia Thrice-Drowned | Has recently dreamed of cold water beneath stone. |
| Brakkus Embervein | Can inspect damaged supports, old mechanisms, and unsafe tunnels. |
| Thoros Reefbinder | Can track movement through mud, rubble, and riverbank terrain. |
| Sister Caldris Vale | Believes river, storm, and stone are warning that something is wrong. |
| Kharzug Ironbound | Recognizes military-style tunnel discipline without knowing who is responsible. |
| Vaelith Sunsong | Has collected old songs mentioning Kridorfrost, the bridge, and drowned foundations. |
Choosing 6 of 7 PCs for Razored Labyrinth (Pathfinder 2e)
Goal
With seven proposed player characters, one must sit out. The objective is to determine which six create the strongest Pathfinder 2e party while maintaining excellent combat effectiveness, exploration capability, social flexibility, and long-term campaign synergy from Level 1 through the Darklands finale.
The Seven Characters
| Character | Primary Role | Secondary Role | Unique Contribution |
|---|---|---|---|
| Auren Voss | Rogue | Scout / Trap Expert | Stealth, infiltration, pirate knowledge, traps |
| Brakkus Embervein | Gunslinger | Engineer | Ranged damage, salvage, firearms, submersibles |
| Kharzug Ironbound | Barbarian | Main Tank | Frontline control, reach, intimidation |
| Nemeia Thrice-Drowned | Witch | Battlefield Controller | Debuffs, hexes, occult knowledge |
| Sister Caldris Vale | Warpriest | Healer / Off-Tank | Healing, divine support, frontline backup |
| Thoros Reefbinder | Ranger | Animal Companion | Tracking, survival, wilderness combat |
| Vaelith Sunsong | Bard | Face / Party Buffer | Inspire Courage, diplomacy, Recall Knowledge |
Pathfinder 2e Role Coverage
A strong PF2e party wants the following covered:
| Role | Importance | Best Candidate |
|---|---|---|
| Frontline Tank | Essential | Kharzug |
| Secondary Frontliner | Very High | Caldris |
| Healing | Essential | Caldris |
| Battlefield Control | Essential | Nemeia |
| Party Buffs | Extremely High | Vaelith |
| Scout / Traps | Essential | Auren |
| Ranged Damage | High | Brakkus |
| Wilderness Guide | Useful | Thoros |
Unlike many RPGs, Pathfinder 2e rewards stacking different bonuses rather than stacking identical damage dealers. Every character should ideally provide something that nobody else does.
Character Analysis
Auren Voss — Rogue
Strengths
- Best scout
- Handles traps
- Lock specialist
- Highest stealth
- Strong infiltration
- Pirate contacts fit campaign perfectly
Weaknesses
- Lowest durability among martials
- Damage depends on flanking
Party Value
Very difficult to replace.
Without Auren:
- nobody reliably disables traps
- exploration slows considerably
- many dungeon hazards become dangerous
Replacement Difficulty: ★★★★★
Brakkus Embervein — Gunslinger
Strengths
- Excellent ranged damage
- Engineering knowledge
- Firearms
- Salvage expert
- Critical to submersible storyline
Weaknesses
- Reload taxes action economy
- Slightly terrain dependent
Party Value
His Engineering Lore is almost unique to this campaign.
Mechanically, however, another martial can usually replace his combat contribution.
Replacement Difficulty: ★★★☆☆
Kharzug Ironbound — Barbarian
Strengths
- Primary tank
- Reach weapon
- Excellent Athletics
- Controls chokepoints
- High damage
Weaknesses
- Limited utility outside combat
- Rage slightly lowers AC
Party Value
Every PF2e party wants somebody who says:
"Hit me instead."
Kharzug fills that role better than anyone else.
Without him:
- enemies reach the backline
- Witch and Bard become vulnerable
- healing burden increases dramatically
Replacement Difficulty: ★★★★★
Nemeia Thrice-Drowned — Witch
Strengths
- Hexes
- Battlefield control
- Excellent Recall Knowledge
- Debuffs
- Strong thematic connection to campaign
Weaknesses
- Lowest HP
- Requires careful positioning
Party Value
She makes difficult encounters easier instead of simply dealing damage.
Control magic becomes increasingly valuable after Level 5.
Replacement Difficulty: ★★★★☆
Sister Caldris Vale — Warpriest
Strengths
- Healing
- Divine magic
- Emergency recovery
- Secondary frontline
- Buffs
Weaknesses
- Doesn't specialize as hard as a pure Cleric or Fighter
Party Value
PF2e assumes somebody can recover the party after bad luck.
Caldris provides:
- healing
- restoration
- anti-undead tools
- divine utility
- backup tanking
Without her:
the party becomes much more fragile.
Replacement Difficulty: ★★★★★
Thoros Reefbinder — Ranger
Strengths
- Animal companion
- Excellent ranged or melee damage
- Tracking
- Survival
- Wilderness exploration
Weaknesses
Some exploration duties overlap with Auren.
The animal companion can occasionally complicate:
- ships
- narrow tunnels
- underwater sequences
Party Value
Excellent explorer.
Not essential if another character invests in Survival.
Replacement Difficulty: ★★★☆☆
Vaelith Sunsong — Bard
Strengths
- Inspire Courage
- Diplomacy
- Recall Knowledge
- Flexible spellcasting
- Face character
Weaknesses
Personal damage is modest.
Party Value
The Bard dramatically improves everyone else's effectiveness.
In Pathfinder 2e:
+1 bonuses matter enormously.
A single Inspire Courage often contributes more total damage than another martial attack.
Without Vaelith:
- party accuracy drops
- damage drops
- critical hit frequency drops
- social encounters become harder
Replacement Difficulty: ★★★★☆
Direct Comparison
| Character | Combat | Exploration | Social | Campaign Flavor | Replaceable? |
|---|---|---|---|---|---|
| Auren | ★★★★☆ | ★★★★★ | ★★★☆☆ | ★★★★★ | Very Hard |
| Brakkus | ★★★★☆ | ★★★★☆ | ★★☆☆☆ | ★★★★★ | Moderate |
| Kharzug | ★★★★★ | ★★★☆☆ | ★★☆☆☆ | ★★★★☆ | Extremely Hard |
| Nemeia | ★★★★★ | ★★★★☆ | ★★★☆☆ | ★★★★★ | Hard |
| Caldris | ★★★★★ | ★★★☆☆ | ★★★☆☆ | ★★★★★ | Extremely Hard |
| Thoros | ★★★★☆ | ★★★★★ | ★★☆☆☆ | ★★★★☆ | Moderate |
| Vaelith | ★★★★★ | ★★★☆☆ | ★★★★★ | ★★★★☆ | Hard |
Who Should Sit Out?
Recommendation
Leave out Thoros Reefbinder.
Why?
Everything Thoros contributes can be approximated elsewhere:
- Survival → Auren or Caldris
- Tracking → spells and skills
- Additional martial damage → Brakkus
- Animal companion → useful but not essential
Meanwhile everyone else provides something nearly irreplaceable.
Best Six-PC Party
| Character | Job |
|---|---|
| Kharzug | Tank |
| Caldris | Healer / Off-Tank |
| Auren | Scout |
| Nemeia | Controller |
| Brakkus | Ranged Damage / Engineer |
| Vaelith | Buffer / Face |
This lineup includes:
- Primary tank
- Secondary tank
- Healing
- Divine magic
- Arcane control
- Party buffs
- Trapfinding
- Stealth
- Engineering
- Ranged damage
- Excellent social capability
- Knowledge coverage
- Strong action economy
There are virtually no significant mechanical gaps.
Alternate Recommendation
If the campaign becomes primarily:
- wilderness travel
- hex crawling
- survival
- monster hunting
- overland exploration
then instead remove:
Brakkus Embervein
and keep Thoros.
Outside of the submersible and engineering-heavy portions of the campaign, the Ranger contributes more consistently to exploration.
Final Recommendation
For Razored Labyrinth, the strongest overall Pathfinder 2e party is:
- Kharzug Ironbound
- Sister Caldris Vale
- Auren Voss
- Nemeia Thrice-Drowned
- Brakkus Embervein
- Vaelith Sunsong
This composition provides outstanding role coverage, excellent action economy, minimal redundancy, and scales smoothly from low-level pirate adventures through underwater expeditions and into the Darklands without leaving any major mechanical weaknesses.
Adventure Summary
The Castrovin Sea is vast, storm‑scoured, and treacherous. Most sailors hug the coastline, avoiding the deeper waters and the jagged volcanic maze known as the Razored Labyrinth. Inland, the ancient Bridge of Kridorfrost stands as the only crossing of the Noyrus River for a hundred miles—a cyclopean relic of the fallen Koloran empire. The bridge‑town of Kridorfrost lives by tolls, timber, and river‑trade, but when a sinkhole opens beneath the bridge's lower supports, workers vanish into flooded tunnels, and the town's fragile prosperity begins to crumble.
The heroes begin as locals and outsiders caught in the first wave of the crisis. Their earliest problems are practical: missing workers, a collapsing bridge, strange obsidian fragments in the rubble, and rumours of organised smugglers using the tunnels. Soon the investigation points south to Kridorn, where pirate‑brokers and salvage crews know more than they admit, and to the sea‑stack trading post of Citadel Allatro. What appears to be a local accident becomes something larger: a Darklands‑connected conspiracy using the Razored Labyrinth as a surface breach.
By mid‑campaign, the party leaves the river behind and ventures across the Castrovin Sea—through sea‑stack mazes, submerged ruins, and lost Ninshabur. They uncover evidence of an older power beneath the Castrovin basin, one tied to the ancient cyclopean empire and perhaps even to the Spawn of Rovagug. Locathahs, merrows, Keleshite traders, and salvage engineers all hold part of the truth.
The final arc descends beneath the Razored Labyrinth into dry volcanic caverns and Darklands tunnels. The heroes must decide whether to seal the breach, sabotage the spawning chambers, or expose the conspiracy before the abyssal forces gain a permanent foothold. Victory means saving Kridorfrost and the southern Castrovin coast; failure means the sea lanes collapse, the ancient horror awakens, and the Darklands gain a road to the surface.
Major Story Arcs
| Level Range | Arc | Focus | End State |
|---|---|---|---|
| 1–3 | The Sinkhole Beneath Kridorfrost | Bridge inspection, rescue, flooded tunnels, smugglers' trail | The party learns the collapse was not accidental; obsidian and organised activity point to a larger plot. |
| 4–6 | Kridorn and the Obsidian Trail | Port intrigue, pirate networks, locathah diplomacy, Black Glass Peak | The PCs discover that pirates are harvesting obsidian for a Darklands‑connected intermediary. |
| 7–9 | Lost Ninshabur and the Sea‑Stack Map | Ancient lore, underwater carvings, Keleshite patrons, map fragments | The party recovers the navigational route through the Razored Labyrinth and learns of the ancient connector tunnel. |
| 10–12 | Beneath the Razored Labyrinth | Submersible expedition, sea‑stack navigation, abyssal descent, spawning chambers | The heroes confront Vhargul Soot‑Crowned, sabotage the spawning ground, and collapse the tunnel. |
Adventure Structure Overview
The campaign is built around a sequential expedition model: each arc builds on the previous, and clues from one region lead to the next. The overall threat escalates whether the party pursues it or not.
| Arc | Primary Location | Key Factions | Major Set Piece |
|---|---|---|---|
| Sinkhole Beneath Kridorfrost | Kridorfrost & the Bridge | Bridge‑wardens, smugglers, local engineers | Descent into the flooded tunnels |
| Kridorn and the Obsidian Trail | Kridorn, Citadel Allatro | Pirate brokers, locathah traders, Keleshite navy | Raid on Black Glass Peak |
| Lost Ninshabur | Ninshabur ruins, sea‑stack route | Keleshite antiquarians, undead guardians, locathah shamans | Recovery of the Flayed Map fragment |
| Beneath the Labyrinth | Razored Labyrinth, dry Darklands | Vhargul's crew, Spawn‑like defenders, abyssal cultists | Assault on the spawning chambers |
— Captain Sefira Vex, harbour‑master of Kridorn
Seven PCs — Suggested Character Hooks
This campaign supports a party of up to seven. The following hooks tie each character to the central conflict while offering personal stakes.
| Character Concept | Hook | Personal Arc |
|---|---|---|
| Pirate Rogue (Auren Voss) | Knows the codes and smuggling routes of the Castrovin underworld; has a price on his head in Kridorn. | Betray the pirate network or redeem his name. |
| Undine Sea Witch (Nemeia Thrice‑Drowned) | Dreams of saltwater and old death; senses the disturbance beneath the sea. | Uncover the truth of her drowned visions. |
| Dwarf Gunslinger (Brakkus Embervein) | Salvage engineer who trusts pressure seals and reinforced steel more than prophecy. | Recover and repair the Apparatuses of the Octopus. |
| Half‑Orc Hunter (Thoros Reefbinder) | From far inland, forced to cross waters that erase tracks; travels with a monitor lizard companion. | Track the obsidian raiders to their source. |
| Warpriest of Gozreh (Caldris Vale) | Hears the same warning in river, storm, and stone—the sea is wounded. | Restore the natural balance by sealing the breach. |
| Hobgoblin Bloodrager (Kharzug Ironbound) | Abyssal fury awakened in a failed tunnel war; now seeks to master his rage. | Confront the Darklands lord who awakened his curse. |
| Elf Bard, Lorekeeper (Vaelith Sunsong) ★ new | Scholar‑performer who collects sailor songs, Keleshite poems, and locathah chants; a living archive of the Castrovin's strangest legends. | Decipher the Last Song of Ninshabur—a lost hymn that encodes a route through submerged ruins and warns of something beneath the basin. |
GM Tools & Resources
This section provides quick‑reference tools for running the campaign: random encounter tables, faction summaries, and suggested DCs by level.
Random Encounters by Region
| Region | d8 Encounter | Suggested Level |
|---|---|---|
| Kridorfrost / Bridge | 1. Sinkhole patrol · 2. Collapsing scaffold · 3. Smuggler cache · 4. River‑drake · 5. Cyclopean carving glow · 6. Lost worker · 7. Obsidian shard trap · 8. Tunnel flooding | 1–3 |
| Kridorn / Coast | 1. Pirate press‑gang · 2. Locathah trader · 3. Storm surge · 4. Merrow scout · 5. Salvage operation · 6. Keleshite patrol · 7. Black Glass Peak raid · 8. Sea‑cat pride | 4–6 |
| Ninshabur Ruins | 1. Undead guardians · 2. Trap‑infested vault · 3. Treasure hunter camp · 4. Sandstorm · 5. Cyclopean inscription · 6. Flayed Map fragment · 7. Collapsing floor · 8. Ancient seal | 7–9 |
| Razored Labyrinth / Darklands | 1. Submerged sea‑stack · 2. Spawn‑like guardian · 3. Volcanic vent · 4. Flooded chamber · 5. Obsidian lattice · 6. Scrag ambush · 7. Pressure door · 8. Vhargul's patrol | 10–12 |
Faction Quick Reference
| Faction | Goal | Attitude Toward Party |
|---|---|---|
| Kridorfrost Bridge‑wardens | Secure the bridge, protect trade | Allies if party helps stabilise the structure |
| Kridorn Pirate Brokers | Profit from obsidian and smuggling | Hostile or mercenary; can be bribed |
| Locathah of Citadel Allatro | Guard sea‑stack carvings and Black Glass Peak | Wary but open to negotiation |
| Keleshite Navy (Southern Fleet) | Maintain control, suppress piracy | Suspicious; may view party as rivals |
| Vhargul's Darklands Crew | Complete the connector tunnel, spawn abyssal horror | Always hostile |
Suggested DCs by Level
| Level | Simple DC | Moderate DC | Hard DC | Very Hard DC |
|---|---|---|---|---|
| 1 | 12 | 15 | 18 | 21 |
| 2 | 13 | 16 | 19 | 22 |
| 3 | 14 | 17 | 20 | 23 |
| 4 | 15 | 18 | 21 | 24 |
| 5 | 16 | 19 | 22 | 25 |
| 6 | 17 | 20 | 23 | 26 |
| 7 | 18 | 21 | 24 | 27 |
| 8 | 19 | 22 | 25 | 28 |
| 9 | 20 | 23 | 26 | 29 |
| 10 | 21 | 24 | 27 | 30 |
| 11 | 22 | 25 | 28 | 31 |
| 12 | 23 | 26 | 29 | 32 |
Based on Pathfinder 2E DC‑by‑level guidelines. Adjust for party composition and desired difficulty.
Beneath the Razored Labyrinth
GM-Only Campaign Notes
Core Truth
The sinkhole beneath Kridorfrost is not natural. It was triggered by renewed excavation far below: a project to complete an ancient connector tunnel beneath the Castrovin basin.
The obsidian fragments found in the rubble come from Black Glass Peak, where organized pirates are harvesting the material for a dark purpose.
The campaign begins as a bridge disaster, becomes a smuggling investigation, then expands into a sea expedition and finally a Darklands descent.
Full Adventure Summary
The Castrovin Sea is vast, storm-scoured, and treacherous. Most sailors avoid the deeper waters and the jagged volcanic maze known as the Razored Labyrinth.
The ancient Bridge of Kridorfrost stands as the only crossing of the Noyrus River for a hundred miles. When a sinkhole opens beneath the bridge’s lower supports, workers vanish into flooded tunnels and the town’s fragile prosperity begins to crumble.
The earliest problems appear practical: missing workers, a collapsing bridge, strange obsidian fragments, and rumors of organized smugglers using the tunnels.
Soon the investigation points south to Kridorn, where pirate brokers and salvage crews know more than they admit, and to the sea-stack trading post of Citadel Allatro.
What appears to be a local accident becomes something larger: a Darklands-connected conspiracy using the Razored Labyrinth as a surface breach.
By mid-campaign, the party leaves the river behind and ventures across the Castrovin Sea through sea-stack mazes, submerged ruins, and lost Ninshabur.
They uncover evidence of an older power beneath the Castrovin basin, one tied to the ancient cyclopean empire and possibly to Spawn-like horrors beneath the earth.
The final arc descends beneath the Razored Labyrinth into dry volcanic caverns and Darklands tunnels. The heroes must decide whether to seal the breach, sabotage the spawning chambers, or expose the conspiracy before abyssal forces gain a permanent foothold.
Major Story Arcs
| Level Range | Arc | Focus | End State |
|---|---|---|---|
| 1–3 | The Sinkhole Beneath Kridorfrost | Bridge inspection, rescue, flooded tunnels, smugglers' trail | The party learns the collapse was not accidental; obsidian and organized activity point to a larger plot. |
| 4–6 | Kridorn and the Obsidian Trail | Port intrigue, pirate networks, locathah diplomacy, Black Glass Peak | The PCs discover that pirates are harvesting obsidian for a Darklands-connected intermediary. |
| 7–9 | Lost Ninshabur and the Sea-Stack Map | Ancient lore, underwater carvings, Keleshite patrons, map fragments | The party recovers the navigational route through the Razored Labyrinth and learns of the ancient connector tunnel. |
| 10–12 | Beneath the Razored Labyrinth | Submersible expedition, sea-stack navigation, abyssal descent, spawning chambers | The heroes confront Vhargul Soot-Crowned, sabotage the spawning ground, and collapse the tunnel. |
Adventure Structure Overview
| Arc | Primary Location | Key Factions | Major Set Piece |
|---|---|---|---|
| Sinkhole Beneath Kridorfrost | Kridorfrost & the Bridge | Bridge-wardens, smugglers, local engineers | Descent into the flooded tunnels |
| Kridorn and the Obsidian Trail | Kridorn, Citadel Allatro | Pirate brokers, locathah traders, Keleshite navy | Raid on Black Glass Peak |
| Lost Ninshabur | Ninshabur ruins, sea-stack route | Keleshite antiquarians, undead guardians, locathah shamans | Recovery of the Flayed Map fragment |
| Beneath the Labyrinth | Razored Labyrinth, dry Darklands | Vhargul's crew, Spawn-like defenders, abyssal cultists | Assault on the spawning chambers |
Faction Quick Reference
| Faction | Goal | Attitude Toward Party |
|---|---|---|
| Kridorfrost Bridge-Wardens | Secure the bridge, protect trade | Allies if party helps stabilize the structure |
| Kridorn Pirate Brokers | Profit from obsidian and smuggling | Hostile or mercenary; can be bribed |
| Locathah of Citadel Allatro | Guard sea-stack carvings and Black Glass Peak | Wary but open to negotiation |
| Keleshite Navy | Maintain control, suppress piracy | Suspicious; may view party as rivals |
| Vhargul's Darklands Crew | Complete the connector tunnel and prepare the spawning ground | Always hostile |
Random Encounters by Region
| Region | d8 Encounter | Suggested Level |
|---|---|---|
| Kridorfrost / Bridge | 1. Sinkhole patrol · 2. Collapsing scaffold · 3. Smuggler cache · 4. River-drake · 5. Cyclopean carving glow · 6. Lost worker · 7. Obsidian shard trap · 8. Tunnel flooding | 1–3 |
| Kridorn / Coast | 1. Pirate press-gang · 2. Locathah trader · 3. Storm surge · 4. Merrow scout · 5. Salvage operation · 6. Keleshite patrol · 7. Black Glass Peak raid · 8. Sea-cat pride | 4–6 |
| Ninshabur Ruins | 1. Undead guardians · 2. Trap-infested vault · 3. Treasure hunter camp · 4. Sandstorm · 5. Cyclopean inscription · 6. Flayed Map fragment · 7. Collapsing floor · 8. Ancient seal | 7–9 |
| Razored Labyrinth / Darklands | 1. Submerged sea-stack · 2. Spawn-like guardian · 3. Volcanic vent · 4. Flooded chamber · 5. Obsidian lattice · 6. Scrag ambush · 7. Pressure door · 8. Vhargul's patrol | 10–12 |
Castrovin Sea
Untamable Heart of an Ancient Continent
Temperature: Temperate waters
Hazards: Keleshite navy, piracy, rocs, sea stacks, storms
Resources: Rich trade
The Castrovin Sea lies at the heart of the continent of Casmaron. Its shipping lanes move trade vessels along the coastlines, bringing goods from Kelesh and Iobaria around the continent. Piracy and storms are common, but it is the rocky islets that pose the greatest threat to ships.
Sea Characteristics
Strong winds blow on the Castrovin Sea, furiously kicking up rough waves and swells. Ships that make use of the common trade lanes avoid most of the truly dangerous weather, though downpours, squalls, and thunderstorms still often delay traders.
In the central sea, rock formations make navigation a dangerous business. The floor of the Castrovin Sea is volcanic in nature, and the tips of craggy mountains of cooled lava poke through the sea’s surface. Most of these mountains are basalt, though the fabled Black Glass Peak in the Castrovin Sea contains streaks of pure obsidian running through it. A community of territorial locathahs claim Black Glass Peak as their territory and refuse to allow outsiders to approach it, leading to confrontations between the normally peaceful locathahs and expeditions looking to harvest obsidian.
Sea stacks, smooth-sided columns of eroded stone, rise out of the water along the coastline. Streaks of pale stone layered atop each other show the age of the stacks, worn from headlands into tall columns seen today. Sea stacks can be flat-topped, tapered like obelisks, or even sharpened into wedges like axe blades. While intriguing, the stacks are clearly natural formations. Sailors often nickname distinctive stacks and use them as landmarks by which to navigate. Above the water, birds nest in the crags and worn sides of these sea stacks, while below, fish, crustaceans, and other creatures hunt and hide.
What separates this sea from others is that the Castrovin Sea has a relatively low salinity. Despite this, the sea contains creatures that would normally live in salt water but have adapted to the relative freshness of this body of water.
The temperate waters of the Castrovin Sea are buoyant and pleasant to swim in during the summer along its southern coast. Many coastal settlements have neighboring beaches where villagers can enjoy their leisure time. Docked pleasure craft with brightly colored sails are a common sight, even in the smallest villages.
Sea Denizens
Fish and other marine creatures live in the Castrovin Sea, but in some places these schools are fewer and leaner than one might expect. Fishing is not a strong industry in parts of the sea; the most common species tend to be small, bony, and strongly flavored. The Castrovin Sea, however, is home to significant populations of sturgeon, and their roe is considered a delicacy. The fragile fish eggs are difficult to transport and command a commensurate price. The Castrovin Sea also contains many different types of turtles and tortoises. Smaller communities catch turtles for meat or to sell as pets, and make beautiful dishes and art objects out of their shells.
For the most part, no mundane fish or sea creatures larger than a dozen feet long live in the Castrovin Sea. Sea stacks in open water display carvings that seem to depict larger creatures, but also dolphins and porpoises. Some sages believe these creatures once lived in the sea, but died out ages ago for reasons still unclear. Some who live along the southern coast of the Castrovin Sea believe it’s unlucky to display artwork featuring dolphins in a home, and that to do so is to invite ruin on the family bloodline.
In the eastern waters of the sea, sea cat colonies are known to flourish. In summer months, sailors often spot prides of sea cats sunning themselves on rock formations or beaches. Sea cats rarely threaten ships, and seeing the creatures is more of a curiosity than a cause for alarm. Of course, anyone going overboard in sea cat territory risks encountering one of the ferocious creatures. Tales also circulate about prides of sea cats attacking dinghies and rowboats, usually near fishing villages.
Several intelligent races make their homes in the Castrovin Sea, mainly locathahs, merrows, and scrags. The locathahs are a reclusive folk, staying away from surface settlements for the most part, but willing to talk and trade if the situation demands. In the northwestern ocean, near the sea stack Citadel Allatro, a solitary stack serves as a trading post for locathahs. Every few weeks, locathah traders climb atop the rocky crag and flag down passing ships. They offer nets of fresh mussels and oysters, strings of pearls, and bits of treasure scavenged from the sea floor in exchange for preserved food and metal weapons.
Traders and Pirates
The trader Nals (N female locathah ranger 9) is a common sight at the trading post and knows many captains by name. Nals keeps records of currents, weather conditions, and migratory patterns, and is a good source of information for ships. Nals prefers to trade for stoneworking tools, such as chisels and picks, which are difficult to craft under the water. She uses the tools to record her observations on small stones, using a shorthand only she understands.
The Padishah Empire of Kelesh controls much of the coastline around the Castrovin Sea, particularly the part of the coast that borders their lands, though sometimes their navy extends their patrols—whether their neighbors like it or not. Kelesh guards its waters strictly, with regular patrols by the light cutters of the Keleshite navy.
Piracy is less of a problem near Kelesh, as the heavier Keleshite galleons ruthlessly hunt out pirate ships. Trade is more carefully controlled on the Keleshite coast, though, and import fees are higher, thus some traders prefer to risk the dangers of piracy to obtain a higher payout.
The Razored Labyrinth
Farther from shore, the sea stacks take on a different nature. These stacks are formed from the eroded tops of aquatic mountain peaks, rather than headlands. They often signal rocky formations hidden beneath the surface, ridges that can tear the bottoms off incautious ships. Because these sea stacks mark dangerous waters, countless superstitions have cropped up around them.
The maze of rocky islets, hidden peaks, and sharp-edged sea stacks make the central sea difficult to chart and dangerous to sail. Bold traders and desperate pirates do journey across the Castrovin Sea, but for every ship that makes the trip, three more lie on the sea floor. Sailors call these waters the Razored Labyrinth, and spread wild stories about sunken holds full of gold and jewels languishing on the sea floor beneath the ridges.
One popular legend tells of a ship on which a sailor was murdered, his bloody body found crammed into a barrel. Two crew members had been seen fighting with the murdered man days before and were sentenced to walk the plank for their crime, though both swore innocence. As the condemned stepped off the plank and fell to the waters below, each called out to Iomedae for justice. Instead of plummeting to their deaths, they were changed into twin pillars of stone, one red and one white, each tapered like the tip of a sword. Sailors on the Castrovin Sea call these sea stacks “The Innocents” and consider them lucky to see.
Treasures of the Deep
The most coveted treasure on the Castrovin Sea is an enchanted chart, rumored to reveal safe passages through the Razored Labyrinth. Pirates claim the chart was blessed by Besmara and given to the late Captain Flayed, a notorious scoundrel and supposed favorite of the Pirate Queen.
So named for his favorite tactic for punishing prisoners, Captain Flayed plundered a trade ship stuffed with gold in the midst of a thundering storm, laughing as he cut down the crew. He ordered the enemy captain lashed to the main mast. Flayed whipped his prisoner without mercy, and with each stroke that fell, a map slowly blossomed in bloody lines on the prisoner’s back. Flayed kept up the beating until the prisoner was dead and the map was complete, then ordered the chart cut from the corpse.
Captain Flayed died over a decade ago, but it’s rumored that the most evil and black-hearted pirates find the pitiless chart tacked to the helm when they need it most.
Many of the natural sea stacks in the central stretch of the Castrovin Sea store carvings beneath the water. Both merrows and locathahs have long used sea stacks to inscribe legends, keep records, and detail maps. These records stretch back generations, the oldest ones all but obscured by erosion and age. Researchers specializing in the Darklands believe that 18 of the engraved sea stacks create a map leading to a Darklands entrance at the bottom of the sea, and from there to a treasure chamber in the tunnels below. Most researchers agree the map starts at Casador’s Maw, a sea stack engraved with twisting sea monsters, but no one has traced the cryptic symbols to the end of their trail.
Razored Labyrinth
Beneath the Castrovin Sea · Player Campaign Guide · Pathfinder 1E · Levels 1–14
The Castrovin Sea has swallowed ships, kingdoms, songs, and secrets. Across its central waters rises the Razored Labyrinth, a maze of volcanic sea stacks, black reefs, sudden storms, submerged ruins, and half-remembered routes that even veteran captains fear to chart. Sailors whisper of Casador’s Maw, Citadel Allatro, the Pillars of Trajheir, and the fabled Flayed Map — a legendary chart said to reveal a safe path through waters where entire fleets have vanished.
Your adventure begins far from legendary treasure, in the frontier village of Kridorfrost beside the ancient bridge over the Noyrus River. When a sinkhole opens beneath the bridge and workers vanish into darkness, the first job is simple: descend, rescue who can be saved, and find out whether the bridge will collapse. But the tunnels below are older than the village, older than the road, perhaps older than the people now living along the western Castrovin coast.
The Journey Without Spoilers
From Bridge Collapse to Coastal Mystery
The first leg of the campaign is grounded and immediate. People have gone missing. The bridge matters. Kridorfrost needs answers. Beneath the riverbank, the party will find clues that suggest the collapse was not merely a natural accident. Who was already exploring below the bridge? Why are strange materials appearing where they do not belong? And what do these clues have to do with the wider Castrovin coast?
From Kridorn to the Pirate Sea
The investigation leads south to Kridorn, where traders, smugglers, salvage crews, and pirate brokers all know more than they admit. The party will hear rumors of organized raids near Black Glass Peak, a volcanic formation sacred to locathahs and rich in rare obsidian. Why are pirates risking the Razored Labyrinth for volcanic glass? Who is buying it? Why have ordinary raiders begun acting like disciplined expedition crews?
Citadel Allatro and the Locathah Clues
To push deeper into the mystery, the party travels to Citadel Allatro, a solitary sea-stack trading post used by locathah merchants. There, maritime allies may help the party interpret sea-stack lore, pirate movements, underwater carvings, and old warnings preserved beneath the waves. The sea has its own historians — and they do not always trust surface folk.
Ancient Routes and Lost Ninshabur
Not all maps are drawn on parchment. Some are sung. Some are carved below the tide. Some are hidden in ruined cities that remember catastrophes modern kingdoms barely understand. The party may need to work with Keleshite traders, cross dangerous waters, and seek lost records connected to Ninshabur and the ancient disasters that once shook Casmaron.
Vladmirr and the Question of Descent
Finding a route is one thing. Surviving it is another. How will the party travel beneath the Castrovin Sea? Magic may solve part of the problem, but pressure, darkness, cargo, air, navigation, storms, and hostile depths demand more than a single spell. In Vladmirr, the expedition must seek rare submersible vessels, salvage expertise, repairs, test dives, and allies willing to risk the waters below the Razored Labyrinth.
When the Sea Ends
For much of the campaign, the Castrovin Sea is the central adversary: storms, pirates, hidden channels, drowned ruins, and underwater passages. But eventually the expedition may reach places where the water drains away into steaming volcanic darkness. What lies beyond the sea? Why were old routes hidden? And what kind of enemies wait where even locathah guides hesitate to follow?
Will You Play...
Will you play Auren Voss, the pirate rogue who knows the codes, lies, smuggling routes, and whispered legends of the Castrovin underworld?
Will you play Nemeia Thrice-Drowned, the undine sea witch whose dreams smell of saltwater and old death?
Will you play Brakkus Embervein, the dwarf gunslinger and salvage engineer who trusts powder, pressure seals, and reinforced steel more than prophecy?
Will you play Thoros Reefbinder, the half-orc hunter from far inland, forced to cross waters that erase tracks and swallow scents, with his monitor lizard companion at his side?
Will you play Sister Caldris Vale, the armored warpriest of Gozreh who hears the same warning in river, storm, and stone?
Or will you play Kharzug Ironbound, the hobgoblin bloodrager whose abyssal fury was awakened in a failed tunnel war long before the campaign began?
Party Roles and Expectations
| Role | Covered By | What It Means In Play |
|---|---|---|
| Scout / traps | Auren | Ruins, ships, warehouses, hidden doors, ambushes. |
| Control magic | Nemeia | Hexes, fog, curses, battlefield disruption. |
| Ranged damage / engineering | Brakkus | Firearms, salvage, repairs, submersible work. |
| Tracking / companion | Thoros and monitor lizard | Survival, scent trails, monster pursuit, tunnel work. |
| Divine frontline | Caldris | Armor, mace, healing, divine buffs. |
| Alternate hard frontline | Kharzug | Bloodrage, reach weapons, abyssal melee pressure. |
| Lore / support option | Vaelith, if used | Ancient songs, diplomacy, bardic buffs, history. |
This campaign rewards preparation. The best parties will ask questions, follow clues, preserve resources, respect environmental hazards, and treat maps, songs, carvings, and old warnings as treasure. Combat matters, but so do logistics, repair work, language, diplomacy, survival, and knowing when not to sail into a storm.
Razored Labyrinth
Beneath the Castrovin Sea · GM Campaign Brief · Pathfinder 1E · Levels 1–14
Razored Labyrinth is a long-form maritime-to-abyssal campaign set around the western waters of the Castrovin Sea in Casmaron. It begins as a local investigation beneath the Bridge of Kridorfrost and expands into pirate intrigue, locathah diplomacy, undersea map lore, ruined Ninshabur, recovered submersibles, and finally a dry Darklands assault against a catastrophic excavation project tied to the Pit of Gormuz and the legacy of Rovagug’s Spawn.
Core Campaign Shape
| Levels | Mode | Primary Play | GM Purpose |
|---|---|---|---|
| 1–3 | Frontier ruin investigation | Kridorfrost bridge collapse, rescue, tunnels, smugglers | Introduce ancient infrastructure and the first clue chain. |
| 4–6 | Maritime intrigue | Kridorn, Citadel Allatro, Black Glass Peak | Connect obsidian thefts to organized pirate logistics. |
| 6–7 | Ancient lore expedition | Ninshabur, Keleshite trader patron, underwater map fragments | Reveal the historical precedent for the tunnel project without fully explaining the current plot. |
| 7–11 | Deep maritime expedition | Vladmirr, Apparatuses of the Octopus, underwater route, sea-stack navigation | Make the Castrovin Sea itself the dungeon. |
| 12–14 | Abyssal Darklands assault | Dry volcanic caverns, Spawn-like defenders, tunnel sabotage | Reveal and stop the full conspiracy. |
GM Sequential Plot
Act I — The Sinkhole Beneath Kridorfrost
The campaign opens in Kridorfrost Village, built around the ancient Bridge of Kridorfrost over the Noyrus River. A large sinkhole opens beneath one of the bridge’s lower supports during maintenance, with one worker sucked in and old flooded tunnels exposed. The party is hired for rescue, stabilization, and investigation.
The visible truth is a cave-in. The deeper truth is that renewed excavation far below destabilized a partially collapsed Darklands connector spur. The party finds old stonework, flooded cyclopean chambers, strange tool marks, obsidian fragments, and hints that smugglers had already discovered parts of the ruin before the accident.
Act II — Kridorn and the Obsidian Trail
The party follows trade markings and smuggling clues south to Kridorn, the river-mouth port where piracy, salvage, foreign trade, and relic speculation all overlap. Here they learn of increased pirate activity around Black Glass Peak, a volcanic formation streaked with pure obsidian and claimed by territorial locathahs.
The pirates are not ordinary treasure seekers. They are disciplined, equipped with diving gear, using reinforced ships, and harvesting obsidian in bulk. Their work is organized by a Darklands-facing intermediary who pays local pirates, surface laborers, corrupt brokers, and low-level subterranean agents without revealing the final purpose.
Act III — Citadel Allatro and Black Glass Peak
The party books passage to Citadel Allatro, a solitary sea-stack trading post used by locathahs. There they meet Talaris Wavebreaker, a locathah Wave Rider cavalier, and Shulassa Deepcurrent, a locathah Deep Shaman of the Waves spirit. These NPCs become maritime allies, not permanent land companions.
Talaris has witnessed increasingly organized pirate raids near Black Glass Peak. Shulassa knows that ancient locathah and merrow carvings beneath eighteen sea stacks may form an underwater route through the Razored Labyrinth to a hidden sea-floor entrance. Clues from Black Glass Peak and pirate camps point toward lost Ninshabur as the best place to recover missing map fragments.
Deep Lore and Major Revelations
Act IV — Ninshabur and the Lost Map
The party works with a Keleshite trader-patron to sail toward Ninshabur. This leg gives the campaign broad Pathfinder lore weight: Keleshite trade interests, the ruined memory of Ninshabur, Rovagug’s Spawn, and the ancient fear that some subterranean works beneath Casmaron should never be completed.
In drowned archives, collapsed vaults, and surviving inscriptions, the party recovers enough of the underwater map to follow the sea-stack route. They also discover historical references to an ancient connector tunnel beneath the Castrovin basin. In Ninshabur’s final age, scholars or engineers learned that something below was being excavated toward abyssal regions associated with the Pit of Gormuz. The project was abandoned or interrupted during cataclysmic events tied to the Spawn of Rovagug.
Act V — Vladmirr and the Apparatuses
With the underwater map in hand, the party goes to Vladmirr, a sinking delta-port and salvage hub. Here they must locate, recover, repair, and test two Apparatuses of the Octopus. Assume two party members can function without subs through magic or other means, while four require the two-person vessels.
Act VI — Beneath the Razored Labyrinth
The recovered underwater map guides the expedition through sea-stack routes, submerged ruins, volcanic ridges, drowned transit chambers, and abyssal currents beneath the central Castrovin Sea. The Apparatuses are pressure shelters, cargo carriers, light sources, and survival platforms.
Act VII — The Drying Descent
The underwater passage eventually slopes into geothermal chambers where the sea drains away through vast fissures. Floodgates, pressure doors, and cyclopean seals mark the end of the maritime campaign. Talaris and Shulassa stop here, promising to guard the route, delay reinforcements, and preserve an escape path if the party returns.
Final Acts and Antagonist Structure
In the dry Darklands, the party finally uncovers the full plot. A major Darklands antagonist has organized local surface pirates, Kridorn brokers, low-level Darklands labor, corrupted miners, and abyssal cult specialists into a vast excavation network. The target is the ancient incomplete connector tunnel beneath the Castrovin basin.
Suggested Villain: Vhargul Soot-Crowned
Role: Darklands organizer, tunnel-lord, and logistics mastermind.
Public face: never appears openly in early acts; uses pirate captains, salvage brokers, and mercenary crews.
True goal: complete the connector tunnel and convert a dry volcanic Darklands level into a controlled spawning ground.
Spawn-Like Defenders
Late-game defenders should feel increasingly artificial and unfinished: obsidian-armored tunnel beasts, pressure-warped giants, larval Spawn fragments, abyssal excavation horrors, corrupted Darklands fauna, volcanic siege organisms, and malformed guardians bred to defend the spawning chambers.
Final Objective
The party must sabotage the spawning chambers, disrupt the obsidian containment lattice, defeat or bypass Spawn-like guardians, and collapse the connector tunnel before it links the Castrovin basin to abyssal territories associated with the Pit of Gormuz.