Following the slaying of Utte, The Mad Cannibal, my players eventually made it to the Lighthouse. Having taken the key off Utte's beheaded corpse, some assumed that getting in and lighting the flame would be easy.
I am not that DM.
The lighthouse sits on the highest point of the island, above some sheer cliffs. While most of the island is lushly forested, the approach to the light house is clear of trees, save for some stumps. Utte wants no one sneaking up and lighting the fire that might signal the ghost ship. The structure itself consists of a stone tower, and an attached living space, accessible by a single heavy iron-enforced wooden door.
The door was unlocked by the key, and the party began to explore the lighthouse. It was a grizzly place.
The living quarters contained a broken bed-frame beneath a pile of animal bones, both small and large. Utte can eat animals other than man, but they do not satisfy him any longer. Draped over the pile was a blanket sewn from tanned human skin.
There was also a basin, a counter, a small broken table, and a sturdy desk. Searching the desk uncovered a meticulous log book, apparently kept by the lighthouse's keeper, who had died likely hundreds of years ago. It also eventually (the next day) uncovered a hidden compartment containing a box of sweet-smelling candles. (These candles are lightly magical blessed candles, which burn slow, and whose light is painful to the undead Who Profane The Great Eel.)
Through a doorway was the tower proper, with a spiral staircase leading upwards. The stairs were broken half-way up, preventing easy access to the hatch to the roof. Some rusty stains adorned the floors and walls, and empty sconces were set into the walls.
The spiral staircase also lead down, into the foundations which opened into a natural cavern in the cliffs. In here were more piles of animal bones. Hung from the ceiling beams were cords woven from human hair, binding collections of rings, earrings, necklaces, and bracelets, taken from Utte's victims. He had no need for the wealth, but enjoyed the memories.
There was also a permanently blood-damp heavy wooden table, on which is a stained wood saw and hatchet. The purpose of this table was pretty clear.
Down on the lowest level, through a sloping passage, was a deep cylindrical well, which seemed to go straight down, and through which a breeze and a sucking sound could be detected. Next to the well was an intricately carved grate sized to fit inside the hole, and a broken crank-like mechanism and decayed rope.
The group named it "The Murder Hole." (In reality, the shaft went down to cliff-side caves that fill with water when the tide is high, and allowed the old lighthouse keeper to haul up the sea life left when the tide receded, but who am I to say it's not a murder hole?)
They were not alone here, either, although they could not see, nor detect their enemy for some time. The Paladin's divine sense could not detect anything other than a foul, unholy background funk.
Throughout the scene, I dribbled in phrases like "you don't think there's anything more you can do" or "there's probably nothing more to find there" or, as time wore on, "it's probably hopeless."
They had an NPC with them, who'd they had picked up at another mysterious tower on the Island. There had been strong debate on the topic, but eventually, a combination of kindness, optimism, and superstition won out, and they took the mysterious ancient woman along. It turned out, she was highly susceptible to the deleterious effects of the lighthouse's residents. She seemed to be dying, wasting away, looking like she had lost the will to live. And that was when they managed to detect the tiny invisible magical tendril hooked into her head.
They all left the area, and resolved to come back tomorrow. The sorcerer had terrible dreams of futility and fleeing an enemy he could not escape. Their mysterious Definitely-Not-A-Medusa prayed with her new cleric (which the fighter had agreed to become before jumping into the cannibal's mouth...look, it's a long story ok?) and was able to tell everyone about the candles, which would be an asset to them as they fought...
A terrible creature, composed of the discarded blood, bile, excrement, fingernails, toenails, gristle, teeth, and inedible bits of Utte's victims, or bits that slipped through the cracks in the table. It is possessed by spirits of the devoured, who were born of terror, pain, torture, and hopelessness.
Before manifestation, Dregs ares small, invisible, and nearly undetectable, save for the background negative funk, which can be felt by appropriate detection abilities.
It Eats Hope. It may attach tiny little tendrils to the party, before it is noticed, and drink it. Players will begin to assume failure on most endeavors. The lighthouse can't be lit. No ships will come. They'll just crash on the rocks. There's nothing to be found here. We may end up just like the cannibal. Everything is eventually futile.
When they have drunk enough hope, they may congeal and manifest to quietly attack a lone individual, causing psychic damage as they gnaw at the brain. There is a chance to spot it then, although, unless they can incapacitate someone by doing so, they will usually return to their immaterial state.
The Dregs may be forced to manifest by Turn Undead, the enchanted candles, or a song with hopeful and inspiring themes.
It manifests as a shifting blob, out of which the faces of the deceased may occasionally be seen. Sometimes forms body parts like hands, ears, noses, mouths, feet. Teeth commonly boil to the surface.
It can seep out of any area touched by the blood of the devoured, which constitutes the ground floor and below, as well as any stain on the stairwell.
Speed: 20 ft, ignores difficult terrain, can climb vertical surfaces
Un-manifested: Invisible, immune to all non-magical damage
Condition Immunities: Prone, Poison
Resistances: Non-magical Slashing, Piercing, Bludgeoning
Vulnerabilities: Radiant, Automatically fails INT, WIS, and CON saves, unless it has either surreptitiously drained hope, or used its Cries of the Devoured ability successfully within 3 turns
Blood Draw: +4 to hit, 2d4+2 piercing or slashing damage, gains 1d4 temporary HP
Cries of the Devoured: Terrified sobbing fills the victim's mind. Target creature makes a DC 13 CHA save, or has disadvantage on their next ability check
Merge: Two Small Dregs may merge into a single Medium Dreg, adding their current HP's together, and reducing their AC by 1. Two Medium Dregs may merge into the Dreg Heap. Once the Dreg Heap is formed, additional merges simply add their current HP to the Dreg Heap's, with a cap of up to 10 above its max.
Speed: 25 feet, ignores difficult terrain, but cannot climb vertical surfaces
Properties and immunities as the Dregs.
Multiattack: If the Dreg Heap does not move, it may attack twice.
Absorb: +6 to hit, 1d8+3 piercing or slashing damage, gains 1d4+2 temporary HP
Revenge of the Devoured: Affects all who can hear nearby. The Dreg heap emits a terrible psychic scream. Again, terrified sobbing fills the mind, but now, there are words. Roll 1d8.
- "Utte, please! Please no!"
- "Let me go! Please, let me go! I'll do anything! ANYTHING!"
- praying "Oh Pelo, soon may I see your light, soon may I--No please no no no nononoono-"
- "There's food out there! Wild Pigs! Fruits! Fish! Please, you don't have to do this! Stop!"
- "I didn't want to do it! Captain's orders! Please, you have to underst--!"
- "GET IT OVER WITH ALREADY YOU FLESH EATING PILE OF SHIT!"
- "I'll tell you where the others are hiding! Just let me go!"
- "no no no no nonononononononononononononnononononononono--"
Targets make DC 14 Charisma Saves, or suffer disadvantage on their next ability check. Roll 1d6 each round. Recharges on a 5-6, or when the heap absorbs another lump.
Hey, they lived, and even managed to get themselves rescued! Good for them!