Powerful PCs should be able to survive at enormous depths and pressure without enormous difficulty. Problems of communication and weapon use should require some thought, but ultimately the party should be able to solve these.
- Haymar. King Haymar, a huge-sized marid, is cunning and crafty, but not particularly moral. He readily promises a wish in return for his scepter -- one wish for the whole party, but a mighty wish. He may keep his word or not, depending on his mood. As a marid king, Haymar can use the wish spell for his own ends as well as in granting others' wishes. He can cast or grant a wish every round. However, he is not completely unbound in his abilities. He is restrained from using wish to get back his scepter or imitate its power, reverse time, or undo annihilation. Another more powerful mystery marid enforced this on him in hopes of capturing the PCs for his own ends. Haymar became King of Dalmaashi 20 years ago when he married the child mermaid Queen Ayalya. The Queen recently vanished, and Haymar correctly suspects Delva was involved, but he actually considers this matter neutrally, a fact that has diminished him in his daughter's eyes. The Queen opposed his secret plan to weld his daughter and his slave/vizier into one being, so having her out of the way isn't so bad. Besides, Haymar is now free to consider other mermaids--and even women of other races. Haymar in combat. Haymar is both a powerful warrior with a trident and a mighty spellcaster, capable of using wish every round to simulate any spell of lower level. For a truly challenging effect, allow him a full attack sequence with the trident and a spell casting every round.
- Baylya. Princess Baylya, Haymar's 16-year-old human-sized mermaid daughter, suffers severe depression because her mother disappeared only a few weeks ago. Divinations reveal Queen Ayalya has been utterly destroyed -- unrevivable by wish. Baylya doesn't realize that her mother had discovered Gorgo's tunneling and was murdered by Argon the Death Knight. Gorgo masked the entire incident with his inky abjuring spells, leaving a great dark hole. If she realized how her mother had died, Baylya would stop at nothing to destroy Argon. Baylya is a moderately powerful sorceress. She would be more threatening if she had not concentrated her powers in divination, but as a royal princess of Dalmaashi she's expected to perform as a seer. Fluffy the deep sea angler serves as her familiar. Fluffy, a female, is puppy-dog-sized and survives at much lower pressures than typical creatures of his type thanks to her magical nature. Baylya in combat. Baylya can foresee attacks made against her, plus she can use teleportation or dimension travel as a move action. She is very hard to hit or hurt but has few hit points and little personal strength. She has only weak attacks and a few charm-style offensive spells.
- Nulzuk. The slave/vizier is a huge-sized triton, a combination of titan and merman. Although physically strong, his true might lies in psionic powers developed to the verge of epic ability. He hates surface-worlders because he finds their air-sucking minds disgusting and their lack of gills repulsive. He doesn't even like mermen and mermaids because they have half-human forms, but he can tolerate them. He became a slave to Haymar when he strove to break the marid's will long ago, to force Haymar into giving Nulzuk unlimited wishes. The marid king had the stronger will and dominated Nulzuk. Nulzuk in combat. Nulzuk uses telepathic and psychokinetic psionics at the same time. He also has unarmed combat abilities thanks to his enormous strength, and further enhanced by psychometabolic powers. His titan physique means he has far more hit points than typical for a psi-user.
- Argon. Argon the death knight is a 100-year old evil human knight who drowned when Delva lured him into the sea. He jumped into the water wearing full armor, besotted with the beautiful undead mermaid gladiator. After he died, Delva offered to revive him as a Death Knight if he would swear fealty to her, and of course he did. For a time she favored him with victims taken from ships, bringing them to him still alive using potions of water breathing or similar magic items. Argon would torture these hapless creatures as long as possible before their protective magic wore off. For the last 99 years, though, he has had few visitors. He has nothing to say to anyone, but if provoked into speech he talks in an old-fashioned manner, saying things like "forsooth" and "yea, verily." He also makes a great show of honor but in truth has none. Argon in combat. Argon wields a greatsword of annihilation that destroys anything it hits. Argon has complete control over the sword and wields it as easily as if it were a saber. This frightening weapon requires a strong will to wield and, should a PC get hold of it, will eventually turn against its owner. Other than that, Argon has excellent armor that's magically survived a century underwater.
- Gorgo. A large-sized squid with superhuman intelligence, Gorgo the squizard is the brains behind the evil operations of Delva. The squizard is a powerful wizard in his own right, and his magic hat further enhances his ability. The hat contains his spells like a spellbook, plus it allows him to cast one extra spell of each level he can cast. Before finding the hat in the remains of wreck some 12 years ago, Gorgo's talents had gone to waste. Now that he can cast spells, he's teamed up with Delva in hopes of fusing with her and becoming nothing less than a god. Gorgo in combat. Gorgo specializes in force magic and inky abjurations. Any damage-causing spell he uses can use force instead of whatever energy type it usually employs. Thanks to his hat, he can prepare more than the usual number of spells, which in turn allows him to have an arsenal of low-powered but damaging spells he can cast quickly, in combination with more deadly spells. Gorgo can emit a huge ink cloud at any time. Besides obscuring vision, his ink is deadly contact poison. He has a very strong force armor effect, reasonable hit points, and can use force walls to divide and conquer his foes. Argon's sword of annihilation (which Gorgo fabricated) can make mincemeat of the squizard's abilities, but Gorgo can dispel it or use anti-magic as a defense. Similarly, Gorgo can and will dispel the magic that enables air-breathers to survive in this environment.
- Delva. The undead mermaid gladiator has been in these waters for 1000-years. Her crypt complex predates the creation of Dalmaashi, which was built only 500 years ago. Delva was once the greatest gladiator of all the mermen and mermaids, until she led an unsuccessful coup against the despotic marid king. She and her 16 followers were tied to poles and raised above the waves in the sunlight until they dried out. They were then sealed into the crypt, with a transparent force wall to allow visitors to see the fate of anyone who defies the king. Yet the tyrant had other enemies who eventually assassinated him. Hoping to restore the legendary glory of Delva, these assassins broke into the crypt and attempted to resurrect her. Their plans went horribly awry and they ended up transforming her into a creature much like a lich but with combat abilities instead of spells. She and Gorgo just met a month ago when the squidzard appeared at the one-way force wall outside her crypt. Gorgo brought down the force wall and used a spell to communicate with her. They quickly hatched a plan to fuse themselves, which Delva sees as a way of obtaining both godlike power and a new life.
- Delva and respawning. If defeated, Delva simply respawns in her crypt within a matter of minutes. She can do this three times before the process weakens to the point at which she will need several years to restore her physical stature sufficiently to fight. She always respawns at the place where her phylactery is stored.
- Delva's physical appearance. When first encountered, Delva appears as a 60-year-old woman with cosmetics used to appear much younger. When defeated the first time, she respawns in her crypt as a woman of about 30 years. If defeated a second time, she becomes a 15-year-old girl. The third time she becomes a 7-year-old child, and in this form she can barely fight. If defeated in this form, she can only come back as a 3-year-old, in which form she cannot fight.
- Delva in combat. Delva is top-notch gladiator with a ton of hit points and several magic tridents. She has at least two evil tridents that do extra damage to good creatures, and one of these has a viscous enchantment that further enhances its damage. When encountered in her crypt, she wields Haymar's scepter (see below). Delva does not wear armor, instead relying on her agility. She may need a very high order of spell resistance to stand up to the PCs. The party should not be able to neutralize her without forcing the destruction of her physical form; otherwise her respawning ability will not come into play.
- Defeating Delva. She cannot be permanently defeated so long as her phylactery remains intact. It's hidden in one of the sarcophagi, and she has placed fake versions of it in each of the other tombs. A truly vile party may decide that slaying her form over and over again, forcing her to take younger and younger forms, is the best way to defeat her. Eventually she will become too tiny for them to attack or defeat. Unless they destroy her phylactery, she will return and seek revenge.
- Phylactery. Delva's phylactery is a medal of honor marked with the symbol of an evil human nation. This evil medal need not be difficult to discern from the fakes using simple divination magic, but the party must find it first. Destroying it may release a dread wraith or banshee if the party has not been sufficiently terrorized.Finally, if someone has the bright idea to just keep the phylactery, Delva has the ability to transfer the "phylactery" to any suitable object nearby. She transferred her phylactery from the original emerald to the medal of honor about ten years ago, around the time she acquired her lacedons.
- Mermen. The typical soldier mermen have powers just a little beyond that of a starting adventurer. They have a quasi-military hierarchy with sergeants, lieutenants, and captains of progressively greater power. They maintain a herd of large-sized seahorses in the open sea, not shown on the map. They keep stores of food in Dalmaashi and have a large support group of farmer mermen and mermaids along shallow shelves a few miles off.
- Lacedons. These creatures were once marines of an evil human nation who fell prey to Delva's charms. Their military uniforms survive, complete with symbols on their armbands indicating their fidelity to an evil political movement. These same symbols appear on the phylactery used by Delva. Lacedons are essentially underwater ghouls. They rarely eat, but Delva has no compunctions about torturing them with hunger.
- Mystery marid. In the abyssal depths, through a portal to the Plane of Water, lives a mystery marid with powers far greater than Haymar's. This adventure only hints at the existence of the other marid. The GM should define and detail this creature as desired.
- Why were the PCs on a ship? The PCs intend some kind of oceanic exploration or piracy. Or perhaps they need to take a ship to get to a place that's under dimensional lock or divination scrutiny that prevents magical transport. Or they must accompany heavy equipment or weapons such as frigate's cannons. Or the PCs might have been trying to land a flying ship or other vehicle when either a malfunction or a sudden storm forced them into the deep sea.
- Who and what caused the wreck? Haymar had his slave/vizier Nalzuk snap the hull by using telekinetics on the keel. Haymar has a clear motive for wanting the PCs to come to Dalmaashi so they can recover his scepter. It isn't a stretch to imagine he or Baylya or Nalzuk used divination magic to discern the powers of the PCs, which should be considerable. It's also possible that Delva or Gorgo engineered the wreck, but their motives would be opposite than the intention of the adventure. They would want the PCs to clear out Dalmaashi so they could take over.
- Who else survived? This adventure assumes only the party survived. As an interesting alternative for heroic adventurers, the party can attempt to keep a crew of air-breathing NPCs alive in the face of megalodon attacks and so forth.
Aiming at the Palace of Dalmaashi
With PCs powerful enough to survive at great depths, the temptation to leave the scene may present problems. In particular, the ability to teleport to safety will oversimplify the problem posed by the shipwreck. This area may be on a different plane or a dimensional lock could prevent teleportation without a special key. The GM might instead allow the party to teleport out, but give the party a reason to return.
Possibly the party know or believes the shipwreck left something valuable on the bottom of the sea. The lit-up palace 1,000 ft. down may tempt the party to investigate as well.
This idea brings technology into a fantasy setting. Substitute hand crossbows and repeating hand crossbows if desired.
The micro-torpedo weapons envisioned here use compressed air canisters to turn a propeller at high speed. At this depth, the weapons have a range increment of 30 ft. and probably no use beyond 60 ft. At the lower pressures closer to the surface they will have longer range. They have no value when used outside of water, but they make ranged underwater attacks possible for PCs who might otherwise have no ranged options.
A basic 9mm pistol bullet should, on average, critically wound or kill a normal human. It might have minor effects on a PC of the level.
The single shot versions carried by the mermen have six cylinders like a typical 6-shot revolver, and fully reloading a spent weapon takes several actions.
The automatic fire versions carried by the lacedons should deal much more damage on average. Magazines of 20 rounds load into the handles of these full auto guns in a single action.
Nulzuk came up with the original design for these weapons. Unlike most underwater creatures, he can use telekinetic psionics to shape metal and perform the chemical changes necessary to create these weapons.
Gorgo the squizard improved on the weapons once a lacedon brought him a model. Gorgo's superior intelligence and spell-casting ability, as well as healthy paranoia, allowed him to conceive of and create the full auto weapons.
The scepter creates a new creature out of two. It normally requires seven days of preparation before it can fuse two creatures successfully. If used without preparation, as in combat, it will kill the two creatures by fusing them into an obscene mockery.
Delva might use it this way against the PCs. This requires two touch attacks followed by moderate difficulty saving throws. If both targets fail, they're altered in a horrible sludge and killed. If only one fails, that target suffers a normal polymorph into a harmless form such as an 8-inch dragonfish, and the effect can be dispelled easily enough.
Haymar planned to enforce the "marriage" of Baylya and Nulzuk using the scepter, but Queen Ayalya opposed it. Once she vanished, he started charging the scepter, only to have it stolen by Delva's minions.
Dalmaashi is made of a single piece of limestone intricately carved into precise patterns. All this work was accomplished five centuries ago by a series of wishes. It has only one main level.
The outer walls are all 3-ft. thick or more, and the roof is 5-ft. thick. All chambers have 20-ft. ceilings arched to a peak of 25-ft. in the center. The outer hallway has a 16-ft. ceiling. The towers have two levels. The area shown on the map is slightly elevated on a 3-ft.-high platform. The other level is 60 feet up and reached by the nearby spiral staircase.
The interior doors in Dalmaashi are all 6" limestone, hinges set inside the stone, opening either way, stone loop-shaped handles, and magic locks. The magic allows the doors to open easily to any mermaid, triton, or marid, but prevents other creatures from pulling or pushing them open. The water pressure also makes it difficult for creatures to open these kinds of doors without massive strength or compensating magic.
Delva's Crypt Architecture
The crypt has four distinct types of construction.
Mermaids excavated from limestone areas 14 through 18, including the tunnel between 16 and 17. This area originally housed a small guard unit charged with managing the public display of Delva's tomb. The ceilings are 8-ft. in this area.
Mermaids also excavated from limestone areas 20 and 21, but the tomb is much grander than the other chambers. It contains many intricate symbols designed to remind people of Delva's failed coup and the glory of the now-forgotten despot who defeated her. The ceiling is 20-ft. high in the main crypt. The sarcophagi chambers are all 6-1/2-ft. The doors to the sarcophagi are all lined with lead and obsidian to prevent divination, and they are enchanted to open easily to the hand of any living creature--but an undead must struggle to open them. Delva's strength is such she can readily pull the doors open.
Area 19 is a large natural cavern trapped by the limestone with a 20-ft. ceiling and speleotherms.
The tunnels between 13 and 14, between 16 and 19, and between 19 and 20 are all new, created by Gorgo's force spells carving through solid limestone. For a greater challenge, these may be lined with undead, vampiric coral that saps the life force of anyone who touches them. While this coral may be easily destroyed using positive energy or some other anti-undead magic, it may prove a nasty surprise for characters who "wisely" eschew heavy armor in an underwater environment.