The Obsidian Pact
The Obsidian Pact
A caravan of merchants bearing a sealed artifact has vanished into the Scorched Expanse, leaving only smoke and corpses. The party must track the missing caravan into the heart of a corrupted temple complex where a cabal of cultists has made a pact with a shadow entity to devour the sun itself. Every moment brings them closer to dusk—and the entity's rising.
Read Aloud
The Scorched Expanse stretches endlessly before you—a sea of burnt ochre and shadow that ripples in the heat. But on the horizon, dark smoke curls skyward in sickly plumes, and the wind carries the stench of burning pitch and charred flesh. As you crest a dune, the remains of a merchant caravan sprawl before you like the ribs of a picked-clean carcass. Overturned carts spill silks and spices across the sand, already half-buried by wind. Bodies—or what remains of them—are arranged in deliberate patterns around a central stone plinth, as if positioned by ritual rather than battle. Scorch marks radiate outward from the plinth, blackening the sand in perfect concentric circles. Most disturbing, a single survivor—a merchant guard with a bandaged arm—sits motionless beside one of the bodies, staring at nothing.
Description
The caravan massacre is a ritual site. The guard, Kess Varim, witnessed the kidnapping of the caravan master and the theft of a sealed obsidian chest bound with silver chains. The cultists arrived at dusk three days ago, summoned by symbols drawn in the sand. The bodies form the points of a massive ritual circle. The plinth bears a symbol of a crescent devouring the sun—the mark of the Obsidian Pact. Kess is traumatized but coherent; DC 10 Wisdom (Insight) reveals he is holding back details about what he saw in the temple to the south. The caravan master, Myros Veth, was a secret merchant of magical artifacts. The obsidian chest held a phylactery-like object of ancient power, and the cultists took it willingly—suggesting Myros was complicit or coerced. Search checks (DC 12 Investigation) reveal a torn map fragment pointing to the Temple of Undying Dusk, three miles south. Scavenger birds (harmless) circle overhead but refuse to land on the ritual ground itself.
DM Notes
Allow the party to roleplay with Kess and gather information. The scene is non-combat but atmospheric. If players push Kess about the details, have him stammer and reveal that the cultists wore robes of living shadow—unsettling but not immediately explainable. He mentions hearing chanting in a language "older than sand itself." Do not reveal the cult's full plan yet; plant seeds. The map fragment and Kess's testimony should make it clear the temple is the destination. Reward players who show mercy to Kess with information about temple layouts (he heard the cultists mention "the Hall of Dusk" and "the Sundial Chamber"). Perception check DC 11 reveals the bodies have an unnatural arrangement—they form the points of a star around the plinth, and the blood patterns suggest they were drained rather than slain. The air around the plinth is noticeably colder than the surrounding desert, despite the intense heat.
Read Aloud
As the sun sinks lower, the desert takes on an eerie violet hue. The Temple of Undying Dusk emerges from the sands like a blackened tooth—a pyramid of cracked obsidian and sandstone, its tip crowned with a massive bronze sundial frozen at 6 o'clock. The air grows cold as you approach, and your shadows seem longer than they should be, stretching ahead of you toward the temple's yawning entrance. Wind whistles through apertures carved into the stone, carrying with it the faint sound of chanting—rhythmic, almost musical, but profoundly wrong. At the temple's base, obsidian statues of robed figures line the entrance, their faces worn smooth by centuries, though fresh gouges in the stone suggest they were recently moved or rearranged. The entrance itself is shrouded by a veil of purple-black shadow that swirls and writhes like living smoke. Where the veil touches stone, frost blooms despite the lingering heat.
Description
This is the entrance to the cult's lair. The sundial at the temple's peak moves imperceptibly closer to dusk throughout the session—it is currently 3 hours until true dusk (the moment of the ritual). The shadow veil is a magical barrier created by the Obsidian Pact ritual; it obscures the interior and grants the cultists advantage on Initiative rolls if the party enters unprepared. The veil deals 3 (1d6) cold damage to any creature that passes through it for the first time on a turn or ends its turn in the veil. The obsidian statues are not animated but are deeply unsettling. Arcana check DC 13 reveals the statues are aligned with ley lines that feed power to the temple. The chanting grows louder as the sun approaches the horizon. Perception check DC 12 reveals fresh footprints leading into the temple (the cultists and Myros, taken within the last 8 hours). The entrance is otherwise unguarded.
DM Notes
Set the mood heavily here. The temporal pressure (3 hours to dusk) should be apparent. If the party hesitates, mention that the chanting intensifies slightly every minute—a ticking clock. The shadow veil is not lethal but is designed to damage anyone who enters carelessly, encouraging tactics. If the Ranger uses Favored Enemy on the veil or cultists (fey, undead, or humanoids), adjust accordingly—favor information that the barrier is tied to the cultists themselves. Allow players to research or observe from a distance before entering. The cold aura extends 30 feet from the temple's entrance. Religious checks (DC 10 Religion) reveal this temple predates the current civilization—it may be 1,000+ years old.
Monsters
Tactics
The cultists are zealots who believe the party has been sent by fate to witness their triumph. They do not parley and immediately attack. The four cultists (use Acolyte stat block with +2 to all damage rolls from shadow pact) wear robes that grant them 13 AC and wield scimitars or daggers. The two shadow-bound Animated Armors are controlled by cultist magic—they are slower to move but more durable. The cultists begin by casting darkness spells or attacking from the shadows of the antechamber's pillars. If a cultist is killed, the others become more frenzied and gain temporary advantage on their next attack roll (feeding on the death). The Animated Armors do not have independent tactics but follow basic combat patterns. The encounter is designed to punish the party for entering recklessly and reward tactics such as area denial, light sources, or positioning.
Terrain
The antechamber is a 60-foot-long corridor with a 20-foot ceiling supported by pillars. The walls are lined with alcoves containing ritual candles that cast flickering shadows. The floor is polished black obsidian with patterns of silver inlay depicting a crescent swallowing the sun. Difficult terrain is created by deliberately scattered ritual components (bones, salts, dried herbs) that the cultists use to disrupt the party's movement. The ceiling has cracks that rain small shards of obsidian if the party uses loud area-of-effect spells (Fireball, etc.), dealing 2 (1d4) bludgeoning damage to all creatures in the area. The light sources are controlled by the cultists' ritual magic—the candles are difficult to extinguish and relight if destroyed.
Monsters
Tactics
This is a skill-challenge encounter disguised as combat. The Bearded Devil (renamed Malvex the Hunger-Bringer) is conjured by Shade-Mother Vesica to protect the ritual; it is bound to the chamber and cannot leave. The three cultists maintain concentration on a Ceremony ritual that is actively draining the caravan's remaining merchants from a ritual chamber above. The two Ghouls are spawned from sacrificial corpses and attack mindlessly. The Devil should not be fought directly—instead, the party must disrupt the cultists' ritual (requires three Insight or Religion checks against the cultists' casting, DC 12 each) or damage the ritual focus (a stone altar with the obsidian chest, AC 15, 30 HP) to break the binding. If the party engages the Devil directly, it uses its Beard and Glaive attacks to control space and separate party members. The Ghouls attack from alcoves where corpses are stacked—DC 12 Perception to notice them before they attack.
Terrain
The Feeding Chamber is a vast underground cavern (80 feet long, 40 feet wide) with a 30-foot ceiling. The central feature is the stone altar holding the obsidian chest, surrounded by a ritual circle of silver and bone. Sacrificial corpses hang from hooks above the altar—some are moving, animated by shadow magic. The floor is slick with blood and other fluids, creating difficult terrain. The chamber has two exit doors: one leading north (to the Sundial Chamber) and one to the east (to a lower prison level). Pillars support the ceiling and provide cover. A ritual circle marks the binding point of the Bearded Devil—it cannot move beyond a 30-foot radius of the altar. Shadow pools on the floor are cold to the touch and dim the light of torches and spells (non-magical light sources are reduced to 10-foot radius, magical light to 30-foot radius).
Read Aloud
The party emerges into a cavernous chamber that mirrors the temple's exterior structure—a massive inverted pyramid carved from obsidian and supported by buttresses of white stone. At the chamber's peak (30 feet overhead) is a perfectly circular aperture through which the dying sun is visible, now stained blood-red by the approaching dusk. Below, a massive sundial spans the entire chamber floor, its gnomon casting a shadow that slowly crawls toward the final hour marking. And at the precise center of the dial stands Shade-Mother Vesica, arms raised, her shadow extending far beyond her body's possible reach. Behind her, bound to a stone pillar, is Myros Veth, his eyes closed in concentration or prayer. The air itself seems to vibrate with wrongness—the very fabric of reality is thinning here, and you can see shapes moving in the shadows that have no physical source. A voice that sounds like wind through a crypt whispers from everywhere and nowhere: We feel your presence, little lights. You come to witness the Undying Dusk. How... inevitable.
Description
This is the final confrontation. Shade-Mother Vesica is performing a channeling ritual that, if completed at true dusk (one hour from when the party enters), will allow the Umbral Hunger to block out the sun for 13 days. The ritual requires concentration and can be disrupted by dealing 30 damage to Vesica, forcing her to make a DC 15 Constitution saving throw, or by breaking her concentration (forcing concentration saves against damaging spells). The ritual is not instantaneous—Vesica maintains it for as long as she concentrates. Myros is bound and cannot be easily freed without magic or a successful DC 15 Strength check, but he is an unwilling participant and will provide information if freed (he will reveal the location of his daughter in Vel Aramis and beg the party for mercy). The shadowy shapes in the darkness are manifestations of the Umbral Hunger—they cannot attack directly but will move threateningly and obscure vision. If Vesica is killed before the ritual is broken, the Umbral Hunger will attempt to manifest through her corpse, requiring an additional skill challenge to banish it back to the shadow plane.
DM Notes
This is the climax. Vesica will not flee or surrender—she is utterly confident and will mock the party for thinking they can stop the inevitable. However, she can be reasoned with: she genuinely believes that darkness is better than light and will try to convert the party to her philosophy if they pause to listen. If the party shows uncertainty, she will offer them a choice: surrender now and become her priests in the eternal darkness, or die as obstacles to destiny. Set a firm deadline: dusk is exactly one hour away, and every round that passes brings the shadow closer to totality. The sundial's gnomon shadow moves 1 foot per round toward the final hour—when it reaches the marking, the ritual is complete and the Hunger begins to manifest (a TPK scenario). The aperture overhead will gradually dim as dusk approaches, creating a time-pressure visual. If the party tries to leave the chamber to rest or prepare, the Hunger manifests and hunts them in the corridors—a chase mechanic that drives them back to the chamber.
Monsters
Tactics
Shade-Mother Vesica is a spellcaster (treat as Wizard 7 with dark, shadow-themed spells: Darkness, Shadow Bolt, Animate Shadows, Teleportation via Shadow, Dispel Light). She has 70 HP and AC 16 (shadow-woven robes). Her action economy is: 1 Action (cast Spell or Attack), 1 Bonus Action (concentration ritual or dodge), Reaction (counterspell-like shadow deflection). She begins each turn maintaining the ritual (a bonus action). Her spell list includes Fireball, Cone of Cold, and Telekinesis—but these are shadow variants that deal necrotic damage or impose disadvantage on saves. Two Acolyte cultists stand at her sides, acting as sacrificial shields and casting healing spells. The cultists will move to block attacks and use their bodies to protect Vesica if needed (they are fanatical). Vesica's lair action (she controls the Sundial Chamber): 1/round, she can cause the shadows to shift, creating difficult terrain or obscuring vision in a 20-foot radius. Real shadows in the chamber "move" to attack, imposing disadvantage on attack rolls for affected creatures. After Vesica is reduced to 30 HP or lower, the Umbral Hunger begins to manifest—shadow tendrils erupt from the ground, and new mechanics enter: creatures within 10 feet of the ritual circle must make DC 15 Dexterity saves or be restrained by grasping darkness. This represents the Hunger's desperation to complete the ritual and consumes Vesica's action economy (she must split her actions to maintain the binding).
Terrain
The Sundial Chamber is a perfect circle, 120 feet in diameter, with the ritual circle (20-foot radius) at the center. The floor is inscribed with the Sundial's dial, with hourly markings and zodiacal symbols. The gnomon's shadow crawls toward the final hour. The walls are carved with the history of the Obsidian Pact in pictographs—environmental storytelling that reveals that this ritual has been attempted before and failed (corpses are fossilized in the stone walls, suggesting previous cultists were consumed by their own pact). The ceiling aperture is 50 feet overhead and directly illuminates the ritual circle. As dusk approaches, the light reddens and dims. Pillars and alcoves provide cover. The ritual circle itself is dangerous: creatures within it suffer disadvantage on saving throws against Vesica's spells. If the party breaks the circle or damages the altar holding the obsidian chest (AC 15, 30 HP), the ritual is disrupted, and Vesica must use her full action to re-establish concentration (preventing her from casting offensive spells for 1 round).
A sealed obsidian chest bound with silver chains, containing the crystallized essence of an ancient shadow spirit. If opened, it releases shadow energy in a 30-foot radius (DC 15 Dexterity save, 8d6 necrotic damage). The party should be warned by Myros or discovered through Arcana checks (DC 14). The phylactery is worth 2,500 GP to collectors, but its true value lies in its destruction—it is a key to breaking the Obsidian Pact permanently. If destroyed (smashed, burned in sunlight, or submerged in holy water), it releases the trapped shadow spirit, which immediately flees to the shadow plane, ending the pact's power over the temple.
Shade-Mother Vesica's ritual robes. These are a very rare magic item that grant the wearer AC 16 (robe of protection variant), resistance to necrotic damage, and once per day the ability to cast Invisibility 2/day. However, wearing the robes requires an attunement, and the wearer must make a DC 15 Wisdom save each day or suffer 1 level of exhaustion as the robes slowly corrupt the wearer's soul. The robes are valuable (2,000 GP) but cursed—wise adventurers will sell or destroy them.
A rare magic item found on Vesica's corpse. Allows the wearer to use an action to cast Misty Step, teleporting up to 30 feet to an unoccupied space. The wearer can use this feature 2/day. Once per day, the wearer can cast Pass Without Trace without using a spell slot. A valuable item for the Rogue or Ranger (600 GP value).
A letter revealing that the Obsidian Pact has agents in the city of Vel Aramis, including corrupted members of the city guard. The letter mentions 'the captive in the Sunset Tower' (Myros's daughter, Sera Veth), and implies there are other shadow temples being prepared across the desert. This is a plot hook for future sessions. The letter itself has no monetary value but is priceless for intrigue and investigation.
An uncommon magic item found among the ritual candles. This carved sunstone pendant can be held up to cast Daylight as an action, 1/day. It grants advantage on saves against spells and effects that deal necrotic damage or impose the charmed condition. A powerful item against the undead and shadow magic (400 GP value).
If the party saves any surviving merchants or guards from the ritual, Myros will reward them with 500 GP in gems and a letter of credit for House Veth, good for free travel and supplies at any of the house's trading posts in the realm. Additionally, Myros will provide the party with the location of his private collection of artifacts in Vel Aramis—an adventure hook for future sessions.
Story Hooks
The defeat of Shade-Mother Vesica and the destruction of the Obsidian Phylactery breaks the pact, but at great cost. The party discovers from Myros that his daughter Sera is being held in the Sunset Tower in Vel Aramis by remaining cult members. Additionally, the sealed letter reveals that the Obsidian Pact has been working for decades to establish shadow temples across the desert—the temple in the Scorched Expanse was merely one node in a larger network. The party is now in possession of evidence of a conspiracy that reaches into the highest levels of desert society, setting up a longer intrigue arc. Finally, the destruction of the phylactery releases the trapped shadow spirit, which flees but leaves behind a residual presence—strange shadows in the desert follow the party for days afterward, a persistent reminder that the Hunger still hungers.
Read Aloud
As the final blow lands on Shade-Mother Vesica, her body crumples, and the shadow-woven robes collapse like deflated skin. The ritual circle flares with violent light—not the light of the sun, but an inversion of it, a light that casts no illumination, only deeper darkness. The Umbral Hunger writhes in the chamber, a manifest thing now—writhing tendrils of absolute shadow that scream in a voice that reverberates through bone and spirit. Then, with a sound like reality tearing, it recoils and is pulled back into the depths, fleeing from the failing ritual. The obsidian chest cracks, then shatters, releasing its contents—a crystalline sphere of pure shadow that crumbles to ash in the light of the dying sun. The chamber shudders. Stone dust falls. And then, silence. The aperture overhead clears. The true sun—golden, warm, and utterly real—breaks through the clouds and bathes the chamber in crimson-gold light. The dusk has been averted. The Undying Dusk will never be.
Description
The party has succeeded—the ritual is broken, and the Obsidian Pact is shattered. Myros, freed from his bindings, collapses in gratitude and will provide crucial information about the cult's network, Vel Aramis, and the location of his daughter. The temple begins to collapse slowly—not catastrophically, but definitely. The party has perhaps 10 minutes to escape before the chamber becomes unstable. Kess Varim (if he was given the map fragment earlier) appears at the northern exit, having followed the party into the temple. He looks at Vesica's corpse with a mixture of relief and lingering horror. The caravan merchants and guards who were being sacrificed are dead, their spirits already departed, but their bodies can be recovered and given proper rites. Myros will insist on this, offering whatever aid the party needs. The temple itself seems to exhale—as if a trapped breath has finally been released. The shadows are gone. The cold is gone. The wrongness is gone. What remains is simply an old ruin, no longer hungry.
DM Notes
This is the resolution. Allow the party to have a moment of triumph, but remind them of the cost. The destruction of Vesica and the phylactery is a complete victory, but the larger conspiracy (the network of shadow temples, the remaining cult members, Sera Veth's imprisonment) creates natural hooks for a continuation. If the party is particularly concerned about Myros or Kess, they can choose to escort them back to civilization, potentially gaining allies in future adventures. The temple's slow collapse is not immediately threatening but creates urgency without combat—a skill challenge (Athletics, Acrobatics, or smart use of magic) to escape safely. Reward clever solutions. The party has prevented a catastrophe: if the ritual had completed, the sun would have been eclipsed for 13 days, allowing the Umbral Hunger to feed on the entire region and potentially spread across the world. The stakes were genuinely apocalyptic, and the party's victory is proportionally significant.
Conclusion
Wrap Up
With Shade-Mother Vesica dead and the Obsidian Phylactery destroyed, the ritual collapses, and the Umbral Hunger is banished back to the shadow plane. The party escapes the collapsing temple as the sun breaks through the clouds, flooding the Sundial Chamber with golden light. Myros Veth, now freed from the cult's compulsion, provides crucial information about the Obsidian Pact's true extent and reveals that his daughter Sera is being held in Vel Aramis by remaining cult members. The caravan merchants and guards are given proper burial rites, and the survivors (including Kess Varim) recognize the party as heroes who averted a disaster. The temple, once a nexus of shadow power, is now merely ruins—ancient, haunted, but no longer a threat. The Scorched Expanse, for the first time in decades, will know a normal dusk and a normal dawn. The people of the desert can breathe easier, though they do not yet know how close they came to eternal darkness.
Cliffhanger
As Myros recounts his ordeal, he reveals the true scale of the conspiracy: the Obsidian Pact is not a single cult, but a network of shadow temples spread across multiple cities and deserts. The temple in the Scorched Expanse was merely the first to complete its ritual—others are in progress, and the pact's leadership remains unknown. Additionally, strange shadows have been following the party since they left the temple. Myros becomes increasingly agitated and whispers a warning: "They will know what we did here. They will know. And they will come for us. For her—my Sera. We must go to Vel Aramis. We must go now, before the darkness finds us again." The party realizes that their victory, while decisive, has also marked them as enemies of a much larger, darker force.
Next Session Hooks
- Journey to Vel Aramis to rescue Sera Veth and uncover the Pact's network within the city's government and trade guilds
- Investigate the other shadow temples mentioned in Vesica's sealed letter; each temple represents a potential future crisis if not dismantled
- Discover the true leadership of the Obsidian Pact—the force that commands Shade-Mother Vesica is still at large and has taken notice of the party's interference
- Explore the Sunset Tower in Vel Aramis, where Sera is imprisoned, potentially uncovering forbidden artifacts and ancient secrets that could explain the Pact's origin and goals
Want to create your own?
Create your own session