It is well worth noting that Phantom Island, Phantom Castle, Phantom Strait, and Ghostville all have real names. They don't matter much to anyone other that the archivists and sages, because even the locals use these names for everything. But for those who are sticklers for the details, the crumbling castle on the point, overlooking the dark and stormy strait is Castle Peasebury, the ancestral home of the Peasebury clan, at least until the blood ran out and they were all gone. The last, Earl Colin Peasebury succumbed to a peculiar sort of degeneracy, and though sexually vigorous, produced no heirs. This was three generations ago, and now only the eldest of Ghostville remember anything of them. Ghostville was chartered as a minor port of call, and a fishery under the name of Inmain. The Peaseburys owned most of it, and what they didn't own was under the demense of the freemen's guild, a motley collection of fishermen, merchants, drunks, and vice peddlers. After the last Peasebury passed on, the Freemen took over the island and everything went downhill after that. Inmain grew, plenty of taverns, brothels, lending houses, and enough thieves to steal a kingdom made the island their home. Everyone out for every coin they could get. Now on the maps hanging the Royal Cartographer's Great Hall, Phantom Island is marked as Liddle Warth, and the strait between it and the mainland is known as the Centyre Strait. Ships used to use the strait regularly. The strait has rocky sides but it is deep and the waters are calm. Sailing around the island can be troublesome as there are many unmarked sandbars and rocky outcroppings, so rather than risk a busted hull most ships will sail a day or three out of their way to avoid those dangers. The strait and the good fishing made Liddle Warth, despite it's near non-existent leadership and local corruption, a passably profitable port of call.
Then the phantoms came. The ghosts, and the haints have been bothering the island for near twenty years now. At first, they were a nuisance, a child's joke, or a drunk's intoxicated yarn. Then everyone started seeing them. Most of them were around the castle, and just sort of there. Going through the motions, giving people a rare fright. It became a bit of sport then to spot them.
Then Melvan Marbrand happened. Marbrand was a local of some importance and influence and he and a group of friends went up to Castle Peasebury to do a bit of looting and carrying on. He didn't return, only one of the party did, a young man, though when he came back his eyes were cloudy and blind, and his hair had turned shock white. The lad, Edgarth Florant, told us that the ghosts had swarmed around the castle, and quickly came inside and surrounded them. One of the dead walked right up to Melvan, grabbed him by the neck, and that stout Melvan had screamed, and then withered up like an old man, like the ghost sucked the very life out of him. The ghost killed Marbrand, and then the rest of the party panicked and the ghosts set upon them. They were all slain but one, Edgarth. He told the constable, Edam Clarick, that the leader of the ghosts was none other than Grahar Peasebury, a larger than life man remembered six generations after his death as a vengeful and violent beast, the man who ended rivalries and feuds with swords and spilled blood, and had enough virility in him to spawn a legion of children, and was only brought low by the one foe he couldn't wrap his hands around their neck, time.
The ghosts teem across the island now. Phantom Island. They cluster the most around the castle, and the spectre of Grahar sometimes makes appearances on the parapet of the castle, or bearing a terrible green lamp to the top of the remaining tower. Phantom Castle. The dead sometimes even drift out across the strait, giving fright to ships and already superstitious sailors will now avoid the strait, and the island.
Ghostville is half of what it used to be, the fisheries are still plentiful, but the fishermen had left. Having ghosts stroll across the ocean and climb up into a low riding fishing boat scared most of them away. Most of those who stayed are the worst sort. Criminals, those who aren't afraid of the dead, Ghostville is a thieve's den. The Claricks and the Marbrands are still important names, but they are more the leaders of brigands and pirates than constables or aldermen.
Phantom Island is a small island with one town, Ghostville, and the ruins of a castle overlooking the strait. The island has a large number of ghosts that appear on it. The vast majority of the ghosts are non-descript and harmless, though a handful are dangerous and can kill. The ghosts are the most active at night, and at dusk. Morning and daytime are considered generally safe, though they can still readily appear inside the castle ruins. The ghosts don't venture inside the boundaries of Ghostville, and actively avoid the lone temple.
People of Importance:
Dallin Marbrand - the sort of leader of Ghostville, Dallin Marbrand had a brief career as a brigand on the mainland, but after being maimed in the arm, returned home as a guerilla leader and has an alcoholic cult of personality around him. He tells aggrandized stories about his conquests on the mainland, mostly in terms of men he's killed and women he's conquered. Fighter/Rogue of moderate level, though no longer has use of one arm. Paranoid and prone to violent outbursts.
Aldo Clarick - the 'harbormaster' of Ghostville, Aldo is a tall thin man with a face like an old tree stump. A regular attendee at the Temple, Aldo is queerly religious, as in religious in so far as it protects him from the ghosts and allows him moral superiority over the other island residents.
Karden Palker - captain of the largest ship left on Phantom Island, a large man with a history of privateering, and the most likely to lend a cutlass to a fight. Most likely how the PCs made it to Phantom Island to begin with.
Maycey Salver - An old woman, the island archivist and historian. Keeps the records of the Peasebury's and is attempting to catalog the recurring ghosts on the island. Though old and gray, she has a sharp eye and a sharp mind. And a sharp tongue for young and inexperienced would be heroes.
Stelsa Tarner - social interloper, Tarner can be found in different places on the island, typically in what remains of the archives, the higher end taverns, and hints at being at one of the brothels, but never the one the PCs are at. Tarner is the antagonist of Phantom Island.
The Treasure of the Phantom Castle
There 'were' records that during the time of the Peaseburys that Castle Peasebury became the resting place of not just a tremendous amount of gold, but also a repository of magical items, powerful weapons, and a breathtaking library of books of magic. The location of the treasury and the armory are lost, as the castle was built full of secret passages, hidden doors, panic rooms, traps, and the rest of the sundry list of decadent paranoid protections. Likewise, all references to the Peasebury treasures have been systematically removed from the archives, and the only ones that still list some of the treasures contained are on the mainland, likely far from the island in imperial or Royal archives, and considering the time that has passed, they are nowhere near the current events section.
Plot Hook 1: The PCs have been tasked with finding a specific item, and the last known location of the item was in the treasury of Castle Peasebury. The PCs now how to find where the castle and the island are, a bare bones minimum of six decades after the fact, and after a major power shift and name change on the island itself. This is further exacerbated by the fact that someone has been deliberately removing or altering all references to the castle and the island to prevent it from being found.
The contents of the Peasebury treasury and arsenal are open to whatever needs to be placed in them. The more fantastic, the better.
The Phantoms of Phantom Island
The majority of the phantoms on phantom island are spectres and apparitions, completely harmless things, glowing lights and the decayed visages of the dead. The most these things can do is cause a chill in the air. The locals know these are, despite being highly unsettling, mostly harmless.
There are more advanced phantoms who are nearly complete beings and can affect the world around them, can and do talk in a drawn out nonsensical pattern, and whose touch causes exhaustion and strange frostbite like burns. While seldom malicious, the locals know to avoid them, and to use folk charms to ward them away.
The worst is a collection of 6 phantoms. These six, archived by Maycey Salver, are dangerous figures from the island's past and are the aggressive dead, will pursue foes, and demonstrate the sharp and poisonous intelligence of the dead. The known dead are as follows
Grahar Peasebury - Ghost/Warrior, accomplished combatant with exceptional skill in hand to hand fighting and takes morbid pleasure in strangling foes to death, this penchant remains even in death and Grahar's victims are throttled about the neck until Grahar's phantom nature devours their lifeforce. A barrel chested heavily bearded man.
Ryden Blackmyre - Ghost/Murderer, the youngest of the island phantoms, Blackmyre was hung from the gallows and left to rot twenty years ago for a string of grisly and violent murders. His preferred victims were young women. In death, Blackmyre will pursue female victims above others. A wiry and weasel like man.
Shale Bywater - Ghost/Musician, the eldest, Shale was a troubadour who traveled the land during the height of Peasebury power and was a regular in the castle. Also a regular in Lady Peasebury's bed. When Earl Lawsen Peasebury discovered this, he had Shale tortured, his fingers cut off, eyes gouged out, tongue cut out, genitals hacked off, and left him to die slowly from infection and exposure. Shale appears as a mutilated ghost of his former dashingly handsome self. He is drawn to those who present themselves as leaders and will make horrific strangling noises as he attacks them.
Ammet Saltblack - An Errol Flynn mustachioed pirate swashbuckler, Ammet Saltblack has left a trail of bastard children, broken hearts, broken marriages, and burning ships in his wake. He made Inmain one of his regular ports of call until he made the mistake of angering the wrong prostitute. In a drunken stupor he was stabbed to death by a woman he impregnated and abandoned twice, beat thrice, and never remembered her name. Ammet is a sullen ghost and is seldom seen outside of the ruins of the castle.
Taria Peasebury - formerly a cleric of the predominant religion of the mainland, Taria involved herself in magical studies, fell afoul of a tainted relic in the treasury and was accused of being a Black Sorceress. This was untrue, and believed to be motivated by pettiness between her and her accuser, but did not prevent Taria from being buried alive inside a cask of salt. Tari's ghost is a salt mummified horror with an extreme hatred of members of the clergy or those wearing religious symbols.
Alise Upcliff - the mistress of Keat Peasebury, Alise Upcliff gave Keat six children, all daughters. This infuriated Keat, by reputation a vicious man, to the point that he took all six of his daughters and threw them from the highest point of the castle. Their bodies were never recovered from the rocks below. Alise attempted to murder Keat for his actions, but failed miserably. He had a rope tied around her waist and had Alise hung from the tower so that until she died from exposure, the only thing she could see was the broken bodies of her deceased children. Her ghost remains near the rocks, and she is the one most likely to go aboard ships, looking for her children.
The Ruins of Phantom Castle
Phantom Castle is the central focus of Phantom Island, and the point that the PCs are attempting to reach. Here the arsenal and treasury are to be found, along with their wealth of gold, treasures, cursed relics, ancient tomes, and all that jazz. The castle is an Imperial Pattern keep that did double duty as a primitive lighthouse. Ships passing through the Centyre strait could navigate using the castle as a point of reference. In times of hostility, the castle was unassailable from the sea, but by virtue of it's height, could rain down ballista and scorpion fire on the ships approaching the harbor or the strait.
The castle is officially uninhabited. During the last generations of the Peasebury family, the castle was allowed to fall into severe disrepair. Many of the wooden roofs have collapsed. The stonework remains passable solid, but anything wooden is questionable. Wooden floors sag, doors are either swollen shut from moisture, or have rotted to crumbly softness. Stairs are dangerous, as some were stone with wood surfaces, others were just wood and can turn into a long fall into a shaft of broken timbers.
There are a large number of dead bodies inside the castle, most belonging to locals who attempted to enter the caste at night, such as Melvan Marbrand, who's corpse still decorates the main foyer. Others belong to mainlanders who came to the island looking for the same things the PCs were looking for. Investigation should reveal that the main cause of death was phantom in nature, leaving behind almost mummified remains that are somewhat resistant to the local environment. A handful of others do not display phantom mortality but that they met their end by other means. This should be a tip off that there is something more afoot here than just a haunted castle.
Enter Stelsa Tarner
Tarner is revealed to be a bit of a savant on the castle and the history of the Peasebury clan, but this requires major quicktalking or some other social interaction to get her to reveal this. She knows about the forays to the castle, about the dead bodies. She has also lead a few groups up there, for coin, or for a dare, or a private tryst since no one can ever seem to catch her working at the brothel. Tarner will attempt to persuade the PCs to leave the castle and the island.
There is no treasure, no arsenal full of weapons and wonders. Earl Colin Peasebury was a decadent and degenerate man. He was afflicted by maladies of incest and had a prodigious chin, drooled, and didn't have his full wits about him. That said he was obsessed with having an heir to pass on the family line, but was simply infertile. This didn't stop him from squandering the family wealth on quack cures, exotic potions, equally exotic whores, and vain attempts to buy healing from the clergy, or purchase that which no sane person would sell, and funding equally ridiculous expeditions to bring back a cure for his soft member and barren seed.
Stelsa Tarner is an illusionist Sorceress, and she has spent the last two decades on the island hunting for the treasure of the castle. While superficially haunted, Stelsa used her magic to creature ghostly illusions to keep people away from the castle and away from where she was actually looking. The main problem is that there wasn't a single treasury or arsenal, there were many, and she is still looking for the big one. In her search she broke open a vault of inequity, a holding place for cursed or deemed evil objects that couldn't or shouldn't be destroyed. She was familiar with such things like vaults of inequity, and was suitably prepared. She did discover a number of necromantic artifacts, which she used to call forth and place six ghosts under her control. The six recurring ghosts are her minions and are bound to do as she commands, as she has a black diamond set into a silver necklace she wears.
The Corpsefallen Necklace of Olira Peasebury-Vass
The necklace was a creation of Lartel Vass, an accomplished nethermancer and speaker for the dead. He took a black diamond he found by chance and made it into a receptacle of nethermantic energy and gave it to his wife, the Lady Olira. Lartel Vass dealt extensively with the undead, fighting them, and destroying them, containing them where he could, and he created the necklace as a form of protection for his wife. He did not long survive his craft and met his end near the Obtort ward and left Olira without a husband or children. Olira returned with several of Lartel's tools and books, and placed them in a funeral shrine for his spirit. The necklace has since been corrupted and is now a powerful necromantic tool, and allows for the summoning, banishing, commanding, and otherwise control over the dead. With it Stelsa can raise zombies, skeletons, and ghosts for a short amount of time, and has bound the six to her command. She also uses the necklace to protect herself from the ghosts and from the rare undead who have appeared on the island.
The Vass Black Treatise
The Vass Black Treatise is a grimoire of nethermancy, also known as white necromancy as it deals with the undead from a lawful good perspective and is more ancestor veneration than raising corpses and releasing marauding ghosts.
Once threatened, Stelsa will call on her ghostly host to attack the invading PCs. She will fall back behind them and will use her magic to support the ghosts as they attack. A common trick she will use is to project illusions of the ghosts so that the PCs dont know which ghost approaching them is real, and which is just an illusion. She will also create situational illusions such as floors falling away, hiding actual holes in the floor, and using the black diamond to cause the corpses in the castle to rise as highly durable zombies. Her last ditch before fleeing is to use a folding crossbow and poison bolts to shoot at more dangerous foes.
Stelsa is not a tremendous fighter, and if defeated, will surrender and sue for peace. She doesn't want to die for the treasures and has rationalized the killings her ghosts have done because most of the victims were themselves criminals or would eventually become criminals. Once surrendered, she can be forced to give over what she's found in her years of searching. If she is killed in the fighting, the PCs will have to find her concealed lair in the ruins of the castle, the cache where she's hidden what shes found but cant use, and her home in Ghostville where her personally ciphered notes are concealed. Taking her alive makes this much easier. She has been keeping secrets for two decades, and is quite good at it.
There are multiple options for how to reward Phantom Island
Oak Island - is there treasure? Who knows. If there is, it hasn't been found yet, but clue after tantalizing clue has been found. Just how deep do the roots of Castle Peasebury go? How far were they willing to go to protect their secrets and their treasure? The PCs find nothing but more clues and a few scraps to keep them on the chase.
A Meager Reward - with the help of Stelsa's notes (or Stelsa if she lives) the PCs find out Stelsa's cover story is true. The Peasebury wealth was long ago squandered, and the castle was left to rot because in the end, Colin Peasebury was a degenerate and a beggar. The PCs get a few dozen or hundred GP for their efforts, and a few token items.
The Unsullied Tomb - the PCs find what amounts to a burial chamber, and it is loaded. It is also funeral gold and grave silver and is thus cursed. Whoops.
The Coffers and Opened - the PCs find a large section of the treasury and a princely reward inside. They are well rewarded for their efforts, but if it becomes common knowledge, the King will demand his cut of the wealth, as will any guilds the PCs are part of. This can kickstart an epic save the gold campaign, or see the PCs give most of their newfound gold away to prevent becoming enemies of the crown and church.
The Armory is Opened - the PCs find an armory of Imperial style weapons and armor, the least of which are masterwork grade, and there should be several magical items, enough for each member to come away with a trinket and a tool.
Monty Haul - They find the grand treasury, all the gold, all the relics, the Dingus they were hunting, and the works. Bad news, pretty much everyone else on the island is a rogue or a thief and there is almost no way to get everything off of the island safely. Then the King will want his share, and the mercenaries will comes. Do the PCs take what they can, do they bury it and bury the legend and leave it to be forgotten? Lots of RP opportunities. Mo money, mo problems.