The Ghosts of Sharn's Depths
The Ghosts of Sharn's Depths
The party is hired by a desperate merchant to retrieve his daughter from the Cogs—Sharn's sunken industrial underbelly—where she has been taken by a mad artificer who experiments on the living. They must navigate treacherous machinery, corrupted warforged guardians, and the specters of his victims before the next hourly descent of the great grinding gears.
Read Aloud
You slip through the rain-slicked streets of Lower Dura as the afternoon light fades to grey, your boots splashing through fouled runoff. The tavern Korran's Keg exhales a cloud of sour smoke and unwashed bodies as you enter, finding a back booth where a rail-thin man in a water-stained velvet coat sits, clutching an empty glass so hard his knuckles have gone white. His name is Merrix d'Kollarren, and the desperation etched into the lines of his face tells you his story before he speaks a word. On the table before him is a handwritten letter, the ink bleeding through the paper in places, addressed to someone named Elaydren. His hand trembles as he slides three hundred gold pieces across the table toward you.
Description
Merrix hires the party to rescue his daughter Elaydren, who was abducted three nights ago from the Twelve Towers. A warforged servant left a ransom note written in medical terminology and copper filings—evidence pointing to the Cogs. Merrix reveals that the note was signed by "the Convergence," a radical artifice cult that believes flesh should be perfected through forced modification. He admits he cannot afford the official House Medani investigators. He provides a key to a maintenance lift and warns that the gears descend on the hour—a gravitational phenomenon tied to ancient Eberron machinery that crushes anything caught beneath them. The party has three hours maximum to enter the Cogs, find Elaydren, and return.
DM Notes
Merrix knows the Convergence operates somewhere in the Cogs' lower levels. He can provide DC 12 Intelligence (Investigation) checks for clues about the cult's philosophy: they believe warforged evolution is incomplete, and they are capturing humanoids to "accelerate ascension through grafting." If pressed, he admits his daughter was studying artificery and was brilliant—perhaps too brilliant for her own good. The key he provides is real and will open the lift. Use his broken voice and repeated "I cannot lose her" to establish emotional stakes. Any attempt at Deception to ask more coin will automatically fail—he has given his entire savings.
Read Aloud
The maintenance lift shudders as Merrix's key turns in its lock, and you begin a sickening descent into darkness. Rusted cables creak overhead, and the smell hits you like a physical force—decades of machine oil, corroded metal, and something organic and rotten beneath it all. When the lift lurches to a stop, you push open its grating doors to reveal a cavern the size of a cathedral, filled with the massive interlocking gears that form the Cogs. Some are still, frozen mid-rotation; others turn with glacial slowness, their teeth as tall as a man. The sound is rhythmic, hypnotic, and deeply wrong. Your breath fogs in the cold air. Along the western wall, you spot the faint glow of alchemical lamps marking what appears to be a workshop, its entrance sealed by a corroded iron door bearing fresh scratches.
Description
The Cogs are a massive industrial complex carved into the bedrock beneath Sharn, housing the ancient machinery that powers the city's foundational magic. Now, decades of abandonment have made it a haven for vermin, mad cultists, and worse. The party enters via the main chamber where four enormous gears dominate the space. DC 14 Wisdom (Perception) notices that the scratches on the workshop door are recent and that tiny figures—construct-like and humanoid mixed together—move in the shadows between the gears. The temperature drops as the hour approaches midnight; a DC 13 Intelligence (Arcana) check reveals that the gears are beginning to grind in preparation for the hourly descent. The party has approximately 20 minutes before the grinding starts, and anything in the gears' paths will be crushed. Paths between the gears offer cover but require careful navigation—any creature moving through must succeed on a DC 13 Dexterity (Acrobatics) check or take 5 (2d4) bludgeoning damage from a scraping blow.
DM Notes
Describe the sound and smell vividly to establish horror atmosphere. If the party tries to move through the gears before the 20-minute mark, they can do so safely. After the mark, each round they spend in the gear chamber requires a DC 13 Dexterity saving throw, taking 22 (4d10) bludgeoning damage on a failure and half on a success. The workshop door can be opened with a DC 15 Strength check or by using the key from Merrix on a hidden panel (DC 16 Perception to find). The cultists deliberately left scratches to show they're active here. If the party takes more than 5 rounds to open the door once the gears start grinding, they hear a scream from inside the workshop—a deliberate taunt by the Convergence leadership.
Read Aloud
The workshop door opens onto a chamber that reeks of alchemical reagents and spilled ichor. Guttering green-flame alchemical lamps cast sickly light across rows of surgical tools, vials of glowing liquid, and—most horrifyingly—restraint tables slick with blood both old and fresh. On the far wall, a series of cages hold prisoners in various states of transformation: some have strange metallic growths protruding from their flesh, others twitch and gibber from the pain of incomplete procedures. But what stops your breath is the sight ahead: a tall, thin figure in a leather apron stained with fluids you don't want to identify stands over a final operating table. On that table, still conscious and screaming, is a young elf woman—Elaydren. The figure's hands are more metal than flesh, and his eyes glow with a sickly amber light. He doesn't look up as you enter, merely laughing as he raises a wicked surgical implement toward the elf's shoulder.
Description
The workshop is the Convergence's primary modification chamber, roughly 60 feet by 40 feet. Dr. Merrix Blackwell, a half-orc artificer corrupted by exposure to the Mournland's raw magical energies, stands at the central operating table. He is flanked by two Corrupted Warforged Guardians (treat as Animated Armor with added features: 15 hp each, can move together to grapple a medium or smaller creature). The cages hold three innocents who cannot meaningfully fight. Elaydren is conscious but restrained; she is not a combatant and will become a liability if rescued during active combat (the DM should note this as a roleplaying challenge). Blackwell himself is preparing to perform a grafting procedure that will complete within 3 rounds if uninterrupted. The room contains surgical tools that can be used as improvised weapons (1d4 damage) and several volatile alchemical reagents on shelves that can be made to detonate (DC 12 Dexterity check to throw, DC 13 to hit, 2d6 fire damage in 10-foot radius on hit).
DM Notes
This is the encounter's roleplay preamble. Blackwell is a monologuer—he will explain his philosophy for 1-2 rounds before attacking, giving players the chance to act first if they wish. His monologue centers on the notion that flesh is "imperfect clay" and that merging organic and construct elements creates transcendence. He views Elaydren as his "masterpiece" because she has artificer knowledge that will help him perfect his work. If the players attack Blackwell, he screams for his guardians and triggers the combat encounter below. If they attempt negotiation or Deception, Blackwell will pause, amused—but requires a DC 15 Persuasion or Deception check to delay combat more than one additional round. Use his surgical tools and the cages of victims to reinforce the horror theme. Elaydren herself can provide crucial information if rescued (she was tracking Convergence activity for House Cannith) that can serve as a hook for future sessions.
Monsters
Tactics
Blackwell begins combat casting spells from range (Scorching Ray, Witch Bolt, or similar), targeting spellcasters first. He will position himself behind the operating table, using it as cover (AC effectively 18). The two Corrupted Warforged move to flank melee fighters, attempting to grapple and restrain. If either warforged is reduced below 15 hp, Blackwell commands them to pursue any fleeing player—he will not leave the operating table unless forced (his pride in his "masterpiece" overrides tactical retreat). Blackwell fights to incapacitate, not kill; he wants to add the party members to his "collection." If the gears above begin grinding (audible as a deep metallic groaning), Blackwell taunts the party about their time running out. The warforged do not flee but will fight to the death. Blackwell will surrender if reduced to 10 hp or fewer, offering to tell the party where the other Convergence bases are located in exchange for his life—a lie, but delivered with such fervor that it requires a DC 16 Insight check to detect.
Terrain
The operating table provides three-quarters cover to Blackwell. Surgical instrument trays are scattered across the floor; movement through difficult terrain requires a DC 12 Acrobatics check or the mover provokes opportunity attacks. Alchemical reagent shelves line the eastern wall—creatures can knock over reagents as a bonus action, creating a 10-foot-radius burst of caustic vapors (DC 12 Dexterity save, 2d6 acid damage on failure). The cages occupy the northern wall and provide half-cover for ranged attackers but are otherwise non-interactive during combat.
Read Aloud
Blood still dripping from weapons or fingers, you help the young elf to her feet as the workshop trembles around you. Above, the sound becomes deafening—the gears are at their grind. The ceiling cracks, and dust falls in sheets. Through the laboratory's western window, you see a horrific sight: the massive gears have begun their descent toward the workshop itself. You have perhaps ninety seconds before they shred this entire chamber like a press. Elaydren gasps and points to a narrow service tunnel partially hidden behind the reagent shelves—it's not marked on Blackwell's own maps, she whispers, but she glimpsed it when he was dragging her through the workshop days ago. It's tight, and it's dark, and you don't know where it leads. But it's the only way out.
Description
The final scene is a timed escape sequence. The workshop is literally being crushed by the descending gears. The party must navigate the service tunnel in darkness (no light sources provided; they must use their own or suffer disadvantage on attack rolls and Perception checks). The tunnel is narrow (5 feet wide) and carved with the rough tool marks of ancient dwarven artificers. The passage slopes downward steeply and is slick with condensation. Each 60 feet of tunnel traversal takes 1 round of movement. The party must cover 180 feet to reach the exit before the gears crush the tunnel entrance (3 rounds maximum). Creatures who don't move at least 60 feet per round must make a DC 14 Strength saving throw as the crushing force of the gears pulls at them through the narrowing gap, taking 11 (2d10) bludgeoning damage on a failure. If the party attempts to collect loot from the workshop or save the other prisoners, they will not have time to escape. This is a moral choice with consequences.
DM Notes
This is a tense but non-combat scene focused on atmosphere and decision-making. The party cannot fight their way out; they can only run. If they move at full speed, they escape with no issue. If they move slowly or attempt to rescue other prisoners, play up the crushing sounds and the increasing darkness as light sources are buried. Elaydren can guide them through the tunnel if they ask, increasing their speed by 10 feet per round (since she knows roughly where the exit is). If Blackwell survives the encounter and they left him restrained, he will be crushed in the workshop; the party hears his final, defiant scream echoing through the tunnel. Use this to punctuate the horror and the mercy of the gears—even a monster is destroyed by them.
A set of masterwork surgical implements forged with mithral threading. Can be sold for 150 gp or used as crafting tools with a +1 bonus to Artificer checks. The tools are warmed to the touch and hum faintly with residual magic.
Blackwell's encrypted journal detailing three other Convergence bases within Sharn, recruitment methods, and the names of at least twelve victims who were 'successfully transformed.' Decrypting requires a DC 16 Intelligence (Arcana) check or cooperation from Elaydren (she knows parts of the cipher). The notes also reveal that the Convergence answers to someone called 'the Architect'—identity unknown.
A crystalline core salvaged from one of the warforged guardians. It pulses with sickly amber light. A wizard or artificer can study it to gain advantage on a single Intelligence check related to construct creation or Mournland phenomena. Alternatively, it can be sold to a black-market artificer for 200 gp, though doing so will attract negative attention from House Cannith.
Recovered from Blackwell's stores. Each restores 4d4 + 4 hit points when consumed.
Elaydren will provide the party with a House Cannith writ of safe passage throughout Sharn's industrial sectors and a promise that House Cannith will owe them a favor (usable once in future adventures).
Story Hooks
The Convergence Research Notes reveal three additional bases in Sharn that the party could investigate. The mystery of 'the Architect' is left unsolved—a mysterious figure pulling strings from the shadows, suggesting a larger conspiracy involving warforged rights, artificer extremism, and perhaps connections to House Cannith itself. Elaydren hints that someone high in House Cannith might be funding the Convergence, though she cannot prove it. The corrupted warforged core is inherently dangerous and may attract scavengers or black-market artificers seeking its secrets. Finally, the surviving victims from the cages (if the party freed any) will attract the attention of both grateful families and House Medani investigators, creating potential moral complications.
Conclusion
Wrap Up
The party emerges from the service tunnel into the rain-soaked streets of Lower Dura, gasping and battered. Elaydren collapses to her knees, breathing in the night air like it's the first time she's tasted freedom in years. Above, the rhythmic grinding of the Cogs fades to an echo—the hourly descent complete. The workshop and its horrors are now buried beneath hundreds of tons of ancient machinery, and Dr. Blackwell's work is at an end. When they return Elaydren to her father at Korran's Keg, Merrix weeps openly, pressing the full reward into their hands without counting it. But as Elaydren whispers something into his ear—something about House Cannith, about ulterior motives, about the need for secrecy—the joy drains from his face. She cannot tell him the full truth. None of them can.
Cliffhanger
That night, as the party rests in their lodgings, Elaydren appears at their door alone, her movements furtive. She carries a sealed letter marked with the sigil of House Cannith's Lady Merrix of Fairhaven. Inside, a single sentence: "The Architect sends his regards. Watch the skies above Sharn. The Convergence is merely the scaffolding. The real work begins at dawn." No signature. No sender address. But in the margin, a crude drawing of a tower within a tower, repeated three times.
Next Session Hooks
- The identity and true location of 'the Architect'—a shadowy figure who may be a warforged prophet, a corrupted artificer, or something far worse. What does 'the real work' entail? Why the cryptic warning about dawn?
- The three additional Convergence bases mentioned in Blackwell's notes. Do they operate independently or in coordination with the Architect? What is happening at the other sites?
- Elaydren's complex relationship with House Cannith. Is she truly working for them, or is she a victim of their manipulation? Who in House Cannith funded the Convergence, and why? The party may be dragged into Eberron's political intrigue whether they like it or not.
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