I'm writing a heavily water-based campaign set in Golarion, and I'm hoping that I can get some help with ideas for a particular scene.
The players are visiting a friendly Gillman villiage in the Inner Sea, towards the bottom of the twilight zone (3000 ft. below sea level), and they are invited to a festival of Gozreh.
Now what does an underwater festival look like?
What I've got so far:
* Music is provided with a band playing bass instruments like horns and drums. The locals dancing looks a lot like synchronised swimming.
* Food is provided by several vendors preparing fresh seafood, in most cases raw, but in some cases seared with a magical blade enchanted to produce fire (or steam underwater)
* There are games in the form of tests of skill and strength. The tests of skill involve harpooning a bluefin tuna released from a bag (they swim at 44 mph / 70 kmph). The tests of strength involve placing one's arm into a giant clam, then wrenching it back open when it closes.
And after that I'm stuck.
I want to create a reasonably believable event, even if it is underwater with magical fish-people, so I'd like to avoid extravagant displays of magic or anything else that would be out of the reach of a small village.
I feel like the clam would just break arms and then cause tearing, personally.
Now, somehow making a whirlpool and seeing who can swim the longest(with previous records of the five longest time) sounds like a fun idea.
Games can also be silly, like getting a lit candle from point A to point B without using magic. It has to stay lit.
Wrestling an 'octopus’(who is really a Wildshaped Druid, to avoid accidental deaths) would be a good test of strength.
Tests of skill could be giving someone 10 seconds(still 1 round) to look at a pile of treasure and pick out the most expensive item. The person who wins gets a pretty conch shell crown.
*Maybe some of the seafood could be magically chilled. You could also include
*If you think people will argue/worry about the safety of the clam game maybe you could just make it opening the clam to get a pearl (yeah, I know those usually come from oysters). Maybe besides just forcing the clam open there could be an option to influence it with Handle Animal or Knowledge (Nature). Maybe the winner gets to present the pearl to a leader and/or attractive villager. Perhaps this leads to a dance or maybe (perhaps on a coral and seashell altar while the whole village watches - could be time for some Diplomacy to avoid offending the village if you don't want to follow their ancient custom)
*Octopus butler with many serving platters
*Squids with multicolored ink create billowing plumes of color which the PCs can swim and dance through. Perhaps the ink is slightly magical or has psychoactive properties.
*Lighting is provided by phosphorescent organisms like jellyfish etc. Maybe there could be a dance hall where flashing fish swim around among the dancers creating a strobe-like effect.
*Poison from various sea creatures could be used as a drug to enter an "ambient" dreamlike state (Hope Sandoval with gills sings a weird underwater song)
*Perhaps there's a "dark secret" near or under the village, the lair of an aboleth who sometimes influences the villagers. With Veil and other spell-like abilities it could fool them into thinking it is a secluded sage/oracle or perhaps even a priest of Gozreh. In the latter case perhaps the festival has been warped by the monster's influence and the PCs or others could be in danger of being selected as the annual sacrifice.
Pathfinder Maps Subscriber; Pathfinder Roleplaying Game Superscriber
Don't forget the architecture, and especially, lighting. It's gonna be dark down there without some captured luminescent sealife.
The architecture of the Gungan city in Star Wars is perfect for what you describe. Google it, starting with this: http://www.parkeology.com/wp-content/uploads/2016/01/jarjarbinks.jpg
This sort of city has a perfect blend of aquatic and air-breather-friendly environments.
For skill challenges, anything that you can imagine on the surface will be extra cool deep beneath the sea. Seahorse chariot races. Dueling with swordfish. Eel swallowing. Sahuagin baiting. The sky's the limit! (literally)
Thanks for the suggestions everyone, there is some good material here.
As an interesting aside, after reading these comments and doing some googling, it seems that most fantasy underwater environments, such as Gungan city (cited above), have breathable air spaces. Since this festival is happening in the deep sea, I've gone with an entirely water-breather environment, but I'm struck by how many of the standard adventuring activities, such as visiting an inn, stop working as you'd expect in an underwater community.
I like the whirlpool idea. Obviously that far beneath the surface it wouldn't be like a funnel, but still. Either with a conjured water elemental or some other magic (or just an area with a permanently swirling current), the locals swim into the top or any convenient point and get swirled down to the ground or wherever and just have to see how fast they can get out or maybe a ball or bright pebble something is released at the same time and that has to be grabbed, held, or retrieved. As long the whirlpool isn't inherently damaging, the underwater creatures aren't really in danger of drowning. Visiting creatures, however, might see the fun and join in but if they happen to be wearing a necklace or other loose item that's granting them the ability to breath underwater, that might get flung or torn off... causing an element of danger they hadn't considered.
I occasionally think deeply on random things, and aquatic culture happened to be a recent one. Festivals disn't end up as any part of it, but I'll dump my rambling here anyway.
architecture:
Coral is usually pretty slow to grow, so in most cases coral buildings wouldn't be too different from any other source of limestone. Obviously, if particularly fast-growing and scupltable coral is developed, this would change. However, this seems unlikely unless the culture is desperate, given that nobody is doing the same thing with trees on the surface. Particularly well-connected aquatic settlements might just trade for bricks (they aren't terribly good at sealing from water, but it's not really necessary when the house is full of water anyway) and have put together mortar that works underwater.
Bipedal "bottom-walkers" like Tritons or Gillmen might have interior layouts similar to surface architecture, possibly subbing out stairs for just a hollow column (self-powered elevator). Merfolk are likely a lot more used to navigating in three dimensions of water, and probably don't build with discrete planar floors. Space stations may be a source of inspiration here, in both the 3d construction aspect and their discrete chunks matching something where rooms are constructed individually (either being grown or needing to wait a few more weeks for the other half of the bricks). If merfolk use beds, they're probably of the "strap yourself in" variety. In either case, entries would not be restricted to the bottom level. Areas for air-breathing tourists are likely pretty conventional. I don't expect much in terms of dolphin pens, they easily could have domesticated water-breathing animals.
biome differences:
The simplest case is a settlement attached to the bottom in a relatively shallow area, such as a lake or continental shelf. Here, you both have ample light and a ground to anchor yourself, and it's likely closest to surface cultural norms. You're also most likely to have signs of outside contact, like imported building materials or air-filled areas for travellers.
Moving on horizontally before vertically, a culture established mid-ocean is going to appreciate their primary magic crafters a lot more than is normal on the surface. Even if they're primarily nomadic (e.g. following whale migrations how native Americans followed buffalo), some form of spacial anchor needs to be developed so your shelter doesn't drift away without you. It is almost certainly magical, because the bottom is a few kilometres down and extremely dark. Surface travellers will not likely notice much of a nomadic open-ocean group, but will probably know of a magically anchored (or, if sufficiently self-sustaining, current-drifting) city if it crosses near trade routes. Even if the sailors don't look down, there's probably a few instances of pirates appearing from below. These are the more likely to have found a way to produce their own construction materials if they are building things, since there isn't much in the way of large plants or stone. If you want to paste in the Gungun style, I'd do it here.
A deep-ocean but still midwater culture is possibly the most reliant on magical and biotech aid. They'll need light sources if they don't have darkvision, still need anchoring, and food starts to be scarce. I'd look to the drow for inspiration (though alignment may vary) since they're also a (magi)(bio)tech-focused society living in a three-dimensional lightless place full of powerful beasts. While IRL you won't find much of anything this far down, fantasy oceans have a tendency to hide some pretty nasty stuff. Will probably not have heard of surface dwellers.
On the normal pars of the bottom, you can once again expect similar things to darklands cultures. Digging and using the ground once again becomes a possibility, though you'll need transmute mud to rock to get too far on construction. It's still dark and only populated by powerful monsters, and expect substantial defences if they're in the territory. May be aware of artifacts from surface cultures if there's a shipwreck nearby, won't be familiar enough to contextualize them.
Hydrothermal vent communities can probably afford to drop the major focus on divine casting (Create Food and Water OP), since they actually have nonthreatening life to eat. I would still expect advancement, since the vents are important enough that somebody is going to try to magically or technologically boost their usefulness. Highly localized, but could possibly become sprawling metropoles in highly volcanic areas (including mid-ocean ridges). Since said ridges extend pretty far upward (see Iceland), there's the possibility of more contact than other bottom-dwellers, but vents without accompanying mountains would still be isolated
military:
A lot of early human warfare is based on infantry formations, which become less practical at higher dimensions (the Phalanx only works on one side, square formations are weakest on corners, etc). Because of the extra area required to cover every direction, the standard wall of pikes runs into difficulty. Infantry will still be used do to the training required to ride, but cavalry equivalents dominate since their biggest counter is ineffective. Presumably, bipeds are better at staying on their mounts than merfolk, which may explain why Merfolk have invested more into ranged weaponry with the underwater crossbow. If you can't out-dogfight your opponent's lancers, you could at least have a way of beating their reach.
This is going to influence the design and placement of castles and forts. While IRL you often want the top of a grassy hill for the height advantage and maximum view, forts against mountains or cliffs become more attractive when every direction is the same and you want to minimize the enemy's ability to manoeuvre. You're also unlikely to see open battlements underwater since there's no inherent protection by way of height. Expect much of the outer shell to be tightly covered with small windows the same way castle walls are. Gates become much more of a focus when catapults are ineffective, and the chokepoints they provide make storming an underwater castle extremely difficult until somebody develops explosives. Effectively, the only option to breach a domed fortress is siege, which is slow, boring, and useless if they have a lot of internal food production (expect this on most cities that aren't in the sunny shallows). Come to think of it, you don't see many wars between underwater cultures. The ineffectiveness of claiming territory may be why.
