The great sea serpents were once the guardians of our world. They hold the secrets of the deep, and each of their coils is a thousand years old.
Majestic Creatures of Yore, Vol. II
In the age-old dance of predator and prey, a tale of monumental struggle unfolded beneath the most secluded waters. Herein lies the legend of one of the last great sea serpents, a leviathan whose very existence blurred the lines between myth and reality. This majestic creature, known as Thalassor, roamed the abyssal depths and hidden coves, a guardian of secrets sunk and tales untold.
The Last Hunt
Thalassor’s last huntwas marked by an event so rare, it would seal the fate of the serpent. The target of its voracious hunger was a mammoth, a behemoth that had tragically found its way into the serpent’s realm through submerged pathways that connect the Shadowdark. Remnants of an ancient time, these paths occasionally allowed land creatures to venture into foreign domains.
The serpent ensnared the mammoth, constricting it with its massive coils. In a desperate and final act of defiance, the mammoth managed to pierce Thalassor’s flesh with its formidable tusks from the inside. But it was not enough to escape its grim fate. Swallowed whole, it became Thalassor’s last meal. However, the serpent’s victory was short-lived. The wound was grave; Thalassor’s lifeblood mingled with the salt of the sea as it sought refuge in a nearby grotto, a hidden sanctuary known only to the ancient denizens of the deep. This grotto is hidden at the edge of the Shadowdark and an uncharted dungeon. It was here, amidst the sand and moss, that Thalassor came to rest, its body succumbing to the injury sustained. As the serpent’s life ebbed away, a profound silence filled the cave, marking the end of a legend.
Adventure Hook
The Whispering Pearl of Thalassor. This artifact is said to be as large as a human heart and glowing with ethereal light, contains the essence and wisdom of Thalassor, one of the last great sea serpents. It is rumored that the pearl possesses the power to grant its bearer insight into the magic of the seas, including the ability to communicate with sea creatures and command the ocean’s currents. However, the pearl lies within the belly of Thalassor, in a grotto guarded by the spirits of the sea and hidden from the land-dwelling world (0 XP).
Level 6 Adventure
- Danger. Risky. Check for a Random Encounter every 2 crawling rounds and after loud noises (4-in-6 chance).
- Light. Except for area 1, all the areas in the dungeon are dark. All denizens within are dark-adapted.
Getting There
The heroes must delve into the Shadowdark to find one of the ancient passageways that connect the surface to the underground world. It is up to the GM to decide whether their journey is dangerous or uneventful. Either way, the characters reach area 1 after this. The dungeon entrance is marked by an ancient rug, its symmetrical patterns a testament to forgotten craftsmanship, laid upon stairs that descend into a mysterious antechamber. Flanking the entryway, two ancient braziers cast a flickering light, their flames illuminating the threshold to realms untold. An aura of uneasiness invades all those who cross the seldom-visited threshold.
| RANDOM ENCOUNTERS d6 | Details |
| 1 | A sudden tremor shakes the dungeon. Rocks and debris fall on a random character. They take 2d8 damage (DC 14 DEX check). |
| 2 | The ghostly figure of a drowned sailor manifests (shadow). The poor soul is corrupted with anger and attacks the living. |
| 3 | A swarm of hybrid, luminescent fish, escaped from an underground stream. They have wings. And like bats, they traverse the corridors of the dungeon with a soft, guiding light. They like company and stay with the heroes if they act neutral toward them. |
| 4 | The characters experience a vivid vision depicting the epic battle between Thalassor and the mammoth. When the vision ends, all the heroes are aware of the serpent’s carcass lying on the sand, and they all feel the presence of a pearl, coming from within. |
| 5 | A sudden drop in temperature freezes all areas of the dungeon and a current of air turns off all light sources. |
| 6 | The adventurers find a potion of water breathing resting on a garden of underwater flora that thrives without sunlight. |
1. Landing
The characters are not the only ones interested in the serpent’s corpse. A group of one mage, one knight, and two bandits explore this area when they arrive. They are not sure about sharing this quest (Reaction check).
2. Shrine
A stone pedestal cradles a sculpture of a tentacled deity, worshiped by forgotten ancient tribes. This ominous effigy is surrounded by six golden urns and casts an aura of mystique and reverence.
Each of the golden urns is worth 75 gp. Interacting with any of them causes six shadows to coalesce from the darkness and attack whoever disturbs them (4 XP).
- Secret Passageway. A curious character may notice the strange tentacled idol can be pushed aside to reveal a small alcove behind it (DC 14 WIS check to notice).
3. Secret Vault
Three chests lie in the dark. Their origins are veiled in mystery with no clues as to their ownership.
- Treasure (8 XP). The characters may take the following from this room: a gold ring with a black pearl (65 gp), a censer with hooded, skeletal figures (70 gp), a potion of polymorph (200 gp), a jade sculpture of a meditating elephant-man (140 gp), an opal-decorated giant conch shell with silver inlays (250 gp), 457 gp, and 125 sp.
4. Cavern of Bones
This cavern is a sea of sand strewn with the bones of countless creatures. The air is thick with the silence of ages. The remains tell tales of battles fought, lives lost, and the relentless, imminent march of time.
The sea serpents are such powerful creatures that even their dead bodies may still hold arcane power. In this case, the serpent’s carcass has caused these bones to reanimate. A small army of fourteen skeletons rises from the dead and fights the characters until slain.
- Treasure (4 XP). If the characters spend 1 crawling round exploring this area, they find the following buried in the sand: a dagger with emerald in the pommel (120 gp), a pendant with three lambent pearls (120 gp), an ivory horn mug carved with drinking dwarves (35 gp).
5. Nautilus Shells
In a chamber illuminated by an ethereal glow, five nautilus shells rest on beautiful, sand pedestals.
The nautilus shells are arranged in a mysterious pattern that hums with arcane energy. Each of them, when touched, emits a harmonic tone that resonates and echoes throughout the chamber. Melodies can be played. If the heroes investigate for 1 crawling round, a musician, or a clever hero may discover the special magical tune that can be played (DC 15 INT). Creatures that hear this magical series of notes gain a luck token.
6. Grotto
A hidden sanctuary beneath the earth cradles the colossal carcass of the legendary sea serpent, Thalassor. Its once-mighty scales glimmer faintly. Surrounding the sea behemoth, the grotto’s waters allude to secrets about the fabled serpent’s timeless saga.
The characters stand before the sea serpent’s corpse. Its eyes are open but lifeless. The stench of rot is strong but tolerable. The Whispering Pearl of Thalassor lies somewhere inside the dead legendary creature.
- Foreign Territories. Before the characters decide what to do or how to enter, a band of eight sahuagin emerge from the water. They demand that the intruders leave. If they refuse, the fish people fight to the death.
7. The Sea Serpent Innards
To venture within the leviathan’s remains, one must navigate a macabre pathway of sinew and bone. The air is filled with the scent of brine and the absence of a heartbeat long stilled. Faint bioluminescent algae cling to the inner walls, providing dim light.
The characters traverse a road of flesh and pools of gastric acid. It is hard to avoid all of it. Each crawling round, there is a 1-in-6 chance that a random character steps on acid (1d6 damage), or that gastric acid falling from above burns a random item they carry within a backpack.
- The Injury. A character who studies the wound determines this is what killed the serpent (DC 13 WIS).
- Enemies. The serpent’s arcane residue has spawned a lesser water elemental within its body. The heroes encounter it before they reach the stomach (area 8). The mindless monster fights fearlessly until it is destroyed.
8. The Serpent’s Last Meal
Within the cavernous expanse of the serpent’s stomach lies the partially digested corpse of a mammoth. The mammal’s fur and flesh, etched with the corrosive marks of digestive acids, pulsate softly, revealing the inexorable process of digestion.
- Smell. The rotting stench of the mammoth is piercing (DC 13 CON). On a fail, heroes regurgitate for 1 minute before they tolerate the smell. On a fail of 5 or more, they retch and must leave the area for at least 1 crawling round before attempting to endure it again.
- The Pearl. The artifact lies below the stomach. The heroes are free to come up with ways to reach it. However, two swarms of centipedes emerge from the carcass when they pierce the stomach wall. What the brave heroes do with the Whispering Pearl of Thalassor or the possible enemies they shall gain when they take the pearl, are both adventures for another day…
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