A Location: The Old Cave
This is a small location / brief adventure or situation I made for my own game. I haven't tested it out yet, so check it at your own peril.
The Situation
There are 3 basic locations in this adventure, and your players can approach it from either of them. They are:
The Healing Spring, where a local spirit named Hurvana lives. Secretly, she's made a deal with the thing in the cave.
The Local Village. A local family has slowly been missing their daughters in the past two seasons. They disappear one day in the field never to return. In truth, the youngest has been secretly sending them to the cave.
The Old Cave, which is under a ridge and hard to find unless you know what you're looking for. No one knows what's in there but it's generally avoided by the locals. Inside is the Vampire.
The Healing Spring
This can either be a location or an encounter, but if the second, it must be locked in place afterwards.
The players come across a rivulet of warm running water which leads into a nearby river - unusual for these parts. Beautiful singing comes from upstream. If they investigate, they find themselves in a steaming hot spring surrounded by dense bamboo foliage; macaques and capybaras peacefully enjoy a hot bath, but the singing stops shortly before they arrive.
In the waters can be seen dozens of small votive images of goddesses, gold and silver jewellery, bronze statuettes, and other valuables which are very obviously intended as gifts and offerings.
If the players take anything from the pond, a beautiful and terrible dragon will emerge from the stream, with a silver tail, deer antlers, and a doglike face. This is Hurvana, the goddess of this spring and daughter of the god of the nearest river, and she doesn't suffer thieves. She will assume good intentions and ask for her offerings back, but if the players insist, she will attack.
If the players make an offering, the dragon emerges briefly but quickly takes a human-like form, which can be varied - a dragon with a human face, the upper body of a woman, a woman with animal features, etc - and greets them, introducing herself as the goddess Hurvana and saying that those who bathe in her waters are cured of all diseases and injuries. This is true, but there is a caveat.
Anyone who gets in the hot springs after having a gift offered will have a very pleasant bath (and you can heal them a bit or something), but won't be cured very thoroughly. Hurvana will sigh and explain that her powers are weakened by the pact she's made with the Vampire in the Old Cave, and beseech those who seem of heroic stock to help free her from her bond.
Anyone who gets in the hot springs without having a gift offered and generally being rude will be cursed with the mad desire to join her forever beneath her waters. This can be lifted with a sincere apology, a suitable sacrifice (anything the size of a pig or bigger should do the trick), and a pledge to take up her quest. Hurvana will use any pact-sealing magic you have in your setting to ensure compliance.
Hurvana will relate how centuries ago, when humans had left these parts (or not gotten to them yet), she felt extremely alone and abandoned by the world. One day she cried out and He heard her. He came in and offered his companionship, his attention, and his gifts to Hurvana - and when he asked her to magically pledge herself to Him, she did.
Then the evil was revealed: this was a Vampire, and every monday he appears to drink her blood; and once per year, during winter, in the first full moon after the frost lays on the ground for two days, he lays with her and makes her spring cold.
Hurvana doesn't know about any weakness he might have, and seems distressed if pressed further, though if inquired on company, she will mention a young girl with unusual eyes on his side for the past few weeks.
Hariot, in the Local Village
The details of the local village are up to you, put this as a family in whatever you already have.
To involve them with the players, drop a rumour that they're looking for their missing daughters and that they have a reward out for it. Maybe make their father a distant relative of one of the players.
In that village lives a modest family. A father, Ulrik, a mother, Kensen, and their seven beautiful daughters which range from the youngest (which is 16) all the way up to the eldest (30), each 2 years older than the last. The elder sisters are all either married or looking.
All of the sisters have long, beautiful black hair like their father - a very handsome man himself - and green eyes like their mother, except one. The youngest one, who's 16, is named Hariot, and she has short brown hair and one brown eye, while the other is green.
Hariot has a deep inferiority complex of her own making. Her sisters all try to make her feel better about her appearance since, despite looking unusual, she's just as pretty as the others, but it only made her sink deeper into self-loathing. This made her a very easy victim for the Vampire, who approached her two seasons ago. She had been crying after a shouting match with her older sister over her "just not getting it". The Vampire approached gently, offered a shoulder, wiped her tears, and asked if she would like to live and be beautiful forever.
This resulted in Hariot taking that sister into the Vampire's cove and partake in (what she believes to be) her murder, drinking her blood, and being filled with life. She was not turned into a vampire, her master says the transformation will be complete when the other 5 sisters are sacrificed too, but she must go slow so as not to arouse suspicion. As evidence of his word, he's made Hariot believe herself to be more beautiful with illusions.
After taking another sister to him, Hariot's determination became steeled, and he started bringing her along to drink the blood of Hurvana, though she only fills an urn with the blood and brings it to the cave - she doesn't know what the blood is for.
Hariot carries a very guilty conscience about what she has done and witnessed - particularly the bloodlettings of Hurvana every monday - but she believes herself to be in too deep. The pain must go away when she gets what she wants. It won't.
The Old Vampire Cave
Under the ridge, by the broken tree, there is a small dark crevasse which you can barely see most days. Inside is a small corridor that quickly becomes a vaulted chamber carved from the stone. This is the den of the Vampire, with a raised plinth where he sleeps and many scrolls and other literature scattered across the floor.
To the left, an entrance leads to his laboratory; to the right is a "holding cell". This is all there is in the cave. It is well-lit but cold as the grave even in high summer.
The Vampire himself was once a man named Korlarant. He now lives in nihilistic ennui in his cave, more often lost in his ancient memories than doing anything else.
It is very important that Korlarant cannot be killed by regular means. If he is wounded enough by either weapons or magic (or magical weapons), he will just turn to smoke, dissipate, and reform again next monday. This is because he is a "Vampire" in the sense that his soul has been substituted with a spirit of darkness, thus he can't die in a way that a human would understand. His only weaknesses are crosses (or another suitable holy symbol), which he cannot touch or get within 5 metres of, and roosters, of which he is deathly afraid. The only way he can die permanently is by journeying into the Spirit World and wrestling his soul back from the jaws of the dread spirit Nakasa, which has the head of a crocodile and the body of a tiger.
The Vampire wants to protect, acquire, and control Beauty. More importantly, however, he wants to create it. His ultimate goal is the creation of life, the most beautiful creature to have ever existed. His failed experiments moan in existential agony and are released to attack any intruders - shambling mounds of flesh and decomposing piles of elements.
He's been keeping the sisters he abducts in eternal slumber in the right-side chamber, and there are others too. The cave extends quite a bit and there's around 54 other people in there too, some captured in the past 10 years, while some have been there for centuries. They are kept alive and beautiful with the blood of the spirit Hurvana.
Hariot thought her sister was dead because Korlarant drains the people of their blood and fills them with Hurvana's, and the process can be quite gory.
He believes that he'll need 60 people to complete his work, a number sacred to him, and the sisters are the missing link. He doesn't intend on using Hariot as he considers her subpar and flawed; she will merely provide the gross matter and a base vessel for his creation.
In fact, Korlarant's experiment will fail. A competent wizard (which Korlarant isn't) will recognise immediately that his spell is faulty.1
Korlarant isn't blindly evil, however. His appreciation for art is genuine, and he can be convinced to engage in other projects - in his own twisted way, he actually believes that this preservation is ultimately in the interest of all the men and women he's manipulated; and he doesn't see Hurvana as a person enough to believe his actions towards her are harmful.
Endings or something
How to deal with this is up to your players, though I should note that, if Hariot's scheme is revealed, her family would likely disown her and exile her, at least for a year or so.
Putting a rooster or cross either in Korlarant's cave or close to Hurvana will be effective for a litle while, but he'll send his flesh monsters to take it down.
If Hariot is convinced of going faster or the abductions become common knowledge in some other way, the local people will form a mob and go after him. Korlarant will get wind of this and cave in the entrance of his den - which he can access by becoming smoke - and cut out Hariot's tongue.
If Hariot's sister is returned safe and sound, Ulrik will gift a pair of Seven League Boots which he keeps under the floorboards along with other memorabilia from when he was younger. These are fine calf-high boots which allow the wearer to run as fast as a galloping horse, as well as over water as long as they don't stop - though they get tired as usual. Three times per day, they may leap 7 leagues (21 km) in a straight line.
Ulrik will also ask if any of his daughters would be interested in marrying the adventurers, and a few of them very likely would be. Their bloodline was blessed when Kensen, their mother, was young, such that childbearing will always be painless for them; this abundant fertility also means that all of the daughters may get pregnant from other, stranger things, such as dark sentiments, or be chosen to bear the children of deities. Up to you, really.
If your game's XP relies on treasure, I'm sure Korlarant keeps artwork and beautiful jewels in his den. Anyone who steals from him while he has power will have their dominant arm shrivel up until they return it, however. If he's convinced to change his ways, he'll likely part with some of his treasure, the value of which should be adjusted according to the needs of the group.
Up to the DM to decide what the actual product of the spell would be. I imagine some sort of spirit of hate possessing a shambling golem, ready to rampage across the land for a while before ultimately dying of hunger.↩