While the PCs were out battling a group of goblins in the forest they found a map and secret communication between a serpent cult called The Dark Coil. In this bundle, the players find a map of a small dwarven temple built into a craggy cliff. What secret perils do the aptly named dungeon The Shrine of Shadowy Terror have to offer?
This is a one-shot adventure for four level 1 PCs.
Six W’s
Who are the enemies in this One-Shot?
Gelatinous Cubes, Yuan-ti Purebloods, Mimics, Traps
What has happened to cause the PCs to fight?
The PCs have just arrived at the windswept cliffs of the Casador Mountains. It is in these mountains that the dungeon currently resides. Recently, the party has come across a bundle of secret communications from a secret cult that has a base inside of this once dwarven temple. This cult has been employing various henchmen to sow mischief around the local area but up until now, there has been no proof. The party has been hired to stop a group of goblins from assaulting a frontier town close to this forest. After the PCs defeat a group of goblins they find the proof they needed.
If the PCs want to know about the history of this dungeon they would need to make a DC 12 History Check.
Where is this encounter happening?
This encounter is starting off in a forest just south of the dungeon. It is here where the PCs will fight one goblin per party member. Once they defeat the goblins the party will find the map as well as information linking the goblins to this cult.
The entrance to the dungeon is on the eastern side of the map. A winding goat path takes the party to a vine-covered secret entrance that requires a DC 12 perception check to notice. Fifty feet in they will encounter a wooden door that leads into the dungeon and where they run into a member of the cult.
When did this happen?
The PCs arrive at this dungeon a full day after finding the information on the bodies of the goblins. The cult has been active in this area for the past 3 months.
Why are the PCs here?
The PCs have initially been hired by a small frontier town to stop a group of goblins from attacking their hunters and gatherers for the past two weeks. Once they find the secret communications between the cult and the goblin group the PCs will be directed towards a dungeon a half a day’s journey to the mountain range.
How will the PCs deal with this problem?
Once the PCs decide to head into the dungeon they will enter via the eastern side of the map closest to Room 3. It is here where the PCs will find a vine-covered entrance and begin to assault the dungeon.
During their battle through this dungeon, they will encounter all sorts of creatures that have an aberrant bent.
NPCs of Note
Mother Galasta- She is a female Yuan-ti pureblood of long dark brown hair, jade green eyes, and a forked tongue that indicates her serpentine nature. She is using the resources of this cult to slowly carve out an underground network for her employer known as the Coiled One.
Maps
The Shrine of Shadowy Terror (DM Map)
The Shrine of Shadowy Terror (PC Map)
Encounters & Treasure
Listed in the PDF
The Shrine of Shadowy Terror- Goblin Fight
https://www.dndbeyond.com/encounters/87de617e-55ca-4f38-a9a1-de124b661eec
Epilogue
With the defeat of Mother Galasta and her followers, the PCs will learn of a large group of Yuan-ti operating in the area called The Dark Coil and of their leader known as the Coiled One. The town will pay the group their gold and thank them for their aid.
Shoutouts as always to https://donjon.bin.sh/5e/dungeon/ for being amazing resources in creating this one-shot adventure!
