Spec fic takes us to amazing places, from deep space to the ancient past. But one place it rarely takes us is under water, so that’s what we’re talking about today. Dive in as we discuss the unique potential of underwater settings and why almost no one uses them. Don’t worry, we have a few examples that you can still learn from. Plus, as a special treat, Wes does a deep analysis of The Abyss, Oren talks about his weird boat RPG, and Chris professes her undying love for the noble whale shark.
Download Episode 213 Subscription Feed
Opening and closing theme: The Princess Who Saved Herself by Jonathan Coulton. Used with permission.
Show Notes:
James Cameron Aquaman Interview
Twenty Thousand Leagues Under the Sea
Transcript
Generously transcribed by Corwin. Volunteer to transcribe a podcast.
You’re listening to the myth green podcast. With your hosts Oren Ashkenazi, Wes Matlock and Chris Winkle. [opening music]
Wes: Hello, and welcome to another episode of the myth green podcast. I’m Wes. And with me today is:
Chris: Chris
Wes: and
Oren: Oren.
Wes: All right, make sure you’ve got a long supply of rope and put on your diving suits and check your pressure gauges because we’re going underwater.
Oren: Uh, can I get the submarine sound? The, the diving sound, the woo-gah… Woo-gah.
Chris: I like the idea of this… Rope.
Wes: I don’t know, it was literally the first thing that popped to my mind. [laughter] I mean, if I’m going under water, I probably need something, besides my diving suit… Rope, that sounds like it’s always going to be helpful somehow. [laughter]
Chris: Trying to remember that’d be pretty awkward too, the rope.
Wes: It’s not like a breathing tube, thinking about, if you’re in your diving suit, you have to have the tube with the oxygen, feeding it. And then I was thinking “well, I don’t want that to be the, if I need to get pulled somewhere or tied in anchored to something else, it probably shouldn’t be my oxygen tube, but I’ve never been in a diving suit, so I’m not entirely sure how that works.
Chris: Maybe you’re diving because there’s something that needs to be pulled up to a boat. And so you’re diving, holding the rope and then you’re going to tie the rope around something, and then the people in the boat are going to pull it up.
Wes: So there are plenty of reasons why you would need rope underwater. There’s a scenario Chris just mentioned, you do sometimes need to anchor divers to things, sometimes each other. Those are also reasons. Although from what I understand, probably one of the most common diving tools that we could go with is actually a knife, because getting tangled in things is really serious.
Oren: Especially all that rope that you brought. [laughing]
Wes: Yeah, if you brought all this rope down you know?
Oren: So if you’re trying to figure out what the heck we’re talking about today, we are going to be talking about underwater adventures, which turns out is just super underutilized. And, I have maybe an idea of why, and I’m just going to get to it immediately. This is the biggest and best example. I think there aren’t that many underwater adventures because I’m hard pressed to think of a better one than The Abyss. [Chris agreeing]
Chris: Nobody can follow up the best.
Oren: It’s so good. I mean, we’ll get into it later, but if you guys haven’t watched it… You know…
Chris: I have, but it’s been so long.
Oren: You should pause this podcast and go watch it and then come back. [laughter]
Chris: Are you going to spoil it?
Oren: I probably will end up spoiling it. So that’s a big, big red flag right now.
Chris: Okay. Well, we’ll talk about all the things first before the business spoiled.
Wes: Other things first but just so you know, it’s coming.
Oren: I was going to say I’m very disappointed. I was all ready to be like “hey guys, you know, what’s funny about underwater?” James Cameron is dumping on Aquaman for not being realistic enough. And that’s because that’s what all the headlines say, but I actually am reading the interview right now, and that’s not what he said. And I’m disappointed. What he actually said was that this is not the kind of underwater movie he would make, because he’s very detail focused about water and he wants his water movies to be realistic. He’s not saying that Aquaman was bad because it wasn’t realistic.
Chris: I mean, we know what kind of underwater movie he would make because he made The Abyss, right. [laughing]
Wes: Yeah, yeah, exactly. So underwater adventures are cool. I remember really kind of having a fascination with the ocean from a very young age because I had some book of Greek myths that was made for second graders. Whoever wrote it embellished, but there’s that moment where the Gods have defeated the Titans and then Zeus decides that he and Poseidon and Hades are going to cast lots to see who gets to pick first, second and last in control of the three realms, the sky, the water, and then basically the earth or the underground.
Zeus gets to draw first, and I remember that he chooses the sky because it’s big and glorious and encompasses everything. And then there’s a moment in this little book of myth where we get into Poseidon’s head, where he’s chuckling to himself, like “of course that glorious Zeus would do the sky, but what he doesn’t realize is that it’s empty up there and all the great mysteries and treasures and unknown things are in the sea.”
And that’s why Poseidon picked it you know, and I was like “he’s onto something”. Plus he gave the world horses.
Chris: Speaking of mysteries and discoveries, one of the reasons why there’s such incredible opportunity for storytellers that is not being taken advantage of in underwater settings, is because it’s the only current frontier on earth right now. Only 5% of the sea floor, apparently according to a random website, has been charted in detail. And so that’s 95% of the ocean sea floor has not been charted in detail, that equals 65% of the earth surface. It’s a lot.
Wes: Wow, that’s so much.
Oren: Yeah. The other 95% is just covered in Megalodons. [laughter] They’re just everywhere. They just happen to not be in the 5% we’ve looked at.
Chris: And in particular, there’s some very deep ocean trenches that are difficult to explore. If we use the same funding that we use to go to the moon to just look at our own trenches, they’d probably be a lot better mapped out. [Wes agreeing]
So it’s a fantastic opportunity and you can put weird stuff down there and it will have a higher sense of realism than if we believe that there’s some island that nobody’s speaking of, which I was just watching, there’s a Dinotopia show from 2001…
Oren: That’s really bad.
Chris: That’s hilarious that you could watch, I think, for free on Amazon prime. It’s hilariously bad and you know, part of the premise is, originally Dinotopia was set a century ago…
Wes: Victorian times, 1800s.
Chris: But this show, they decided to set it in the modern day instead. So then when the characters crash land on Dinotopia, a big question is, wait, how come nobody knows about this huge continent full of dinosaurs? And the show just doesn’t have a good explanation. Whereas back in Victorian times, that seems a lot more plausible. You know, so that’s where the whole new frontier stuff matters, it’s a lot easier to have weird things there that plausibly in a contemporary setting people haven’t discovered yet.
Wes: Yeah. The underwater is so open because so many things sound plausible. I mean, we brought up Megalodons, and the ocean has hosted just the most magnificent beasts, size, shape, color. The amount of diversity in the ocean is just mind boggling.
And then, you know, it’s not quite an underwater adventure, but I like to think on the scene in Mulana when they go so deep that the water is affected. The pressure is so great that it creates a whole extra world underneath the ocean.
Right where they go to recover his fishhook. What is his giant hook?
Oren: It’s just a hook. Just his fish hook.
Wes: But that’s invented, it’s fantasy, it’s almost plausible. It’s like “Oh, okay. We don’t really know what’s down there. Maybe there, maybe the pressure is so great that there are pockets of open space”, that’s just a different type of area. I don’t know, if there’s underwater volcanoes, there can be anything.
Chris: And it’s worth stating that the blue whale is not just the biggest creature alive. It is the biggest creature to have ever lived on earth. Yeah.
Oren: Maybe, maybe. Yeah. They’ve just recently discovered some fossils that they think might be bigger than the blue whale, but there’s still a lot of debate about.
Chris: is this another sea life?
Oren: Yes.
Chris: Yeah, of course.
Oren: Yeah, of course it was in the sea, but they’re not sure how big this thing was, but some of the more generous estimates suggest it may have been bigger than a blue whale.
Wes: Right.
Chris: The point is that there’s a bigger diversity in wildlife in the sea. You can have bigger, more giant things in the sea, [Wes agreeing] and you could invent a creature that’s bigger than the blue whale that lives in the deep ocean trenches or something. Yeah. And crawls through there, whatever, a water-dragon. Yeah. Whatever it is.
Wes: And it’s cool too, because if you want to get real creative with your fantastic creatures, yeah, the locomotion is different. The body types that you would give them are supported by the water so they’re not bound in the same way that we are, walking around on earth. Just google search images for all kinds of fun stuff, then discover the horror that is the mantis shrimp.
Oren: Oh, everyone loves the mantis shrimp.
Wes: I mean, if there’s any reason for underwater, I mean “tell me why that’s cool?” Just show them that picture. It’s like that thing exists. It doesn’t make any sense, but it exists and it sees in 15 colors or something like that.
Oren: I mean my favorite is always going to be the pistol shrimp, but you know, mantis shrimp is also pretty cool.
Chris: So people know what sees in 15 colors means: so humans generally see in three colors, our eyes actually only detect red, green, and blue, that’s where RGB comes from.
And then all of the colors that we see in the spectrum are just combinations of those three colors that we have actually detected. The mantis shrimp has 15 different detectors for different wavelengths.
Wes: Right, so that actually it’s even more than 15 colors because that’s the cone receptors they have. So it sees…
Chris: It has 15 to R three.
Wes: Right. Oh my gosh. So it sees… Time. It sees time. Yeah. [laughter]
Oren: I bet the arguments about what color to paint the floor and the walls are pretty intense, so many more choices. [laughter]
Wes: Yeah. Other reasons, non-fantastic beasts aside. We talked about whales, I mean, sharks, octopuses, pretty much any…
Chris: I would like to vote for whale sharks.
Oren: Whale sharks are amazing.
Chris: They’re so adorable too, they’re so pretty. [agreement] Dude, if you running out underwater settings, just do me a favor and put whale sharks in there.
Oren: Everybody loves whale sharks. They’re your best friend. They would never hurt you.
Wes: Yeah. They look extremely helpful. They just would want to be your friend. [laughter] So yes, there’s other cool things about underwater adventures. Ruins, right? [agreement] Which since we’ve been bemoaning the lack of underwater adventures, I’m wondering if our post-apocalyptic futuristic stories are going to start accounting for climate change more with the sea level rise, and maybe we’ll have more underwater adventures in the future of fiction.
Chris: I hope so.
Wes: That’d be cool. I mean, I hope that that doesn’t happen like in real life, but I would read those stories very much.
Oren: I mean, there’s that one? What’s it called? SeaWorld? No. The one with Russell Crowe, I think.
Wes: No, it’s Kevin Costner. Waterman…
Oren: Kevin Costner, right. Waterworld. Oh boy.
Wes: The problem with that one is most of it doesn’t take place underwater though. There’s like one scene where he like takes one of the characters under the waves to look at some cities.
Oren: Yeah.
Wes: Most of the action is them trying to find land, which I think kind of doesn’t quite count.
Oren: Why are you running away from the coolest part of your setting? [laughter]
Chris: Maybe why it bombed so badly. [laughter] It’s like just take away all the plot points in Waterworld and instead just insert really pretty underwater cities… Probably would have done better.
Wes: It probably wouldn’t have way better. Yeah.
Oren: Well, underwater stuff is a really great set up for any kind of creepy or horror story because it’s weird and alien and it’s an inherently hostile environment. So there’s a reason that Bioshock is set in an underwater city and it’s not because building underwater cities makes sense. Right. It’s because it’s weird and there’s drips and you could see these giant creatures moving around outside the window and like “ooh, that’s weird.” Also diving suits are just inherently terrifying. So the big daddies with their giant drills and weird dive masks are like “ahhhhh, why?”
Chris: Right. It just automatically takes us out of our element and puts us in a place where like “okay, we’re not adapted to navigate here. But there are lots of very large predators who are.” [agreement]
Wes: Which is kind of fascinating because there certainly are a lot of like similarities between stories that take place in outer space and a story that you could tell underwater. You need specialized equipment to survive in a hostile environment, but Oren’s right. The horror, in my opinion, seems to be a little greater underwater.
For example your protective gear underwater can leak without it bringing on immediate catastrophe. Right. If there’s a whole breach in a spaceship, things getting sucked out. And also in space you can see pretty far.
One of my greatest fears is being in open water because my eyes can only see so far before there’s just nothing. So what’s to stop some super-friendly whale shark from swimming out of the blue nothing and befriending me forever, or a Megalodon. [agreement] I can’t see, most of my senses are just taken away from me.
Oren: I was actually going to say, I think that’s the core reason why underwater is inherently scarier than space because space is defined by being empty. And you can do horror stories about what exists in the deep dark space or whatever, but there’s a general cultural awareness that you can see really far in space. So if there’s anything around, it’s going to have a really hard time sneaking up on you.
Chris: Space is also, you know, considered to be fairly uniform. I mean, it’s almost stretching belief to run into lots of weird things in space. Whereas in the sea not only are there plenty of creatures, but they’re really large, often really threatening creatures. Star Trek likes to do space whales, but they do stretch belief a little bit.
Oren: Unfortunately, gosh, what was that show? There was an attempt to do Star Trek but underwater, [Chris agreeing] I watched a few episodes. It’s amazingly bad, and I’m not really sure why I feel it maybe could have worked.
I think part of the reason it was bad was simply that they weren’t willing to really dig deep into the details. So they were trying to do a ‘planet of the week’, but underwater. And it was harder to accept that there were all these different things down there.
Whereas in Star Trek they have the entire universe. So it’s like “yeah, sure, maybe somewhere out there there’s a planet where these people exist.” Right? That show also demonstrated the early nineties obsession with dolphins. They’re just really into dolphins. Now, if you have a dolphin main character, and like a Wesley Crusher character his main thing is that he can talk to the dolphin. [laughter]
Chris: So any tips for underwater settings? I will say I went to Aquaman just to see the underwater scenery.
Wes: It was pretty.
Chris: It was pretty, not realistic. I couldn’t help but notice, I mean amongst other things, one of the things that was funny about Aquaman is we have this big battle scene. And underwater. And one of the cool things underwater is it’s like the equivalent of having tons of fliers in the air and things on the ground, which adds a three-dimensional element that is really cool. But things kept falling [laughter] after an air battle, you know, a helicopter might blow up because of course every helicopter ever in a movie has to blow up and fall, you know, what are things float? [laughing]
So you don’t have things crash and fall quite so much, but one of the hilarious things in Aquaman is it really felt like the writers didn’t understand how dense water was and that there would be a lot more floating, a lot less falling happening.
Oren: Yeah. I mean, Aquaman is definitely like a super campy movie, right? That’s its thing. And it has its really beautiful underwater shots and that’s all nice. They definitely also have a lot of scenes in the movie that depend on us just pretending that water is basically air that the characters can fly in, which is fine for Aquaman, right?
That’s Aquaman, it’s going to do that. It’s a goofy movie and it’s a nice break from the DC universe’s unending stream of grim dark. But you know, for most stories you want to take water a little more into account because you probably don’t have a multi-million dollar special effects budget.
So you want to help your audience feel like they’re in an alien environment. So for example, a sword fight would be really difficult to have underwater, because swinging anything with any kind of speed is basically impossible. Now you can still fight underwater. There are in fact some cases of, they’re called frogman, this is the term for Navy military divers, where they have gotten into fights underwater, and they’re pretty vicious and they involve a lot of knife stabs. So you could still do that, but it’s hard to have a big epic trident duel underwater, unless of course you are Aquaman and you just don’t care.
Chris: Right. I would say even for Aquaman, part of any type of film and making film is having effects that look real. I think part of the problem with the battle in Aquaman is that intellectually I know that’s not how water works, it looks wrong. [agreement] And even if the movie is silly, that’s still not a good thing for immersion sake, you want your special effects to look real.
But trying to judge what the audience is going to expect and know can be kind of a tough thing, but for writing again, for any setting that has novelty, and underwater settings can have a great deal of novelty, you really do want to realistically portray how it would actually be in water to some degree, because otherwise it might not feel like people are underwater and then you lose all the novelty that you would gain otherwise.
Wes: Yeah. There seems to be this notion that speed is important to keep up threat, you know, it’s like this action sequence has to be like jam packed and stuff, but done right, two opponents in diving suits that only have their diving knives, there’s nothing stopping that from being very tense. And very well shot. And it’s laborious to do stuff underwater because of the pressure. So it could be slow, but still full of tension when done right.
Oren: And I mean, the classic submarine battle is cool and classic for a reason. There’s a lot of built-in factors underwater that really lend themselves well to a very tense written exchange. Because the submarines can’t just start shooting at each other. First they have to find where the other one even is because they have very limited sensory ability, right? You could send out a sonar pulse, but that also tells everyone where you are. And gives them a much more accurate picture of where you are, then it gives you.
Also, it hurts whales, that’s why you shouldn’t use active sonar in real life, just society PSA.
That may not matter to your characters, but just an important thing, so you have this whole thing of the subs, trying to find where each other are, using really tiny noises that they’re trying to interpret. There’s a reason that Hunt for Red October is a really good movie, it uses that to full effect. [agreement] And you can do that too. You can use that in your story and it just gives you a lot to work with.
Wes: Can we talk about The Abyss now? [agreement]
Oren: Let’s talk about The Abyss. [laughter] Tell me about The Abyss.
Wes: So, there’s a crew and they work, I think, it has been a couple of years since I’ve seen it, but I believe that they work in this large rig that’s deep on the ocean floor and they’re collecting resources or oil or something like that. [agreement] They’re basically a large rig that’s down very deep on the ocean floor that has a commercial enterprise. But a few new people arrive and they are military because this rig happens to be close to a submarine, I think it was Russian, that had been destroyed and landed apparently not too far from where this rig was several years ago. They’re going there to recover some nuclear warheads or to make sure that those are intact, recover them and take them back above the surface for proper disposal.
Complications happen and the main rig itself gets kind of pushed and pulled near an abyss, basically a massive underwater trench, and the other thing that they foreshadow early on is, because they’re so deep, the pressure and the knowledge of where you are, is enough to put such pressure on someone’s cognitive well-being that they can start to suffer ill effects just from being in that highly pressurized environment, which does play into the plot, well, with some of the characters.
I don’t really want to spoil the whole thing, as so much is going on, because they have little tiny Outrigger vessels that kind of have a main home base and the large ship, there’s antagonism between the characters and their conflicting motivations. And then also aliens, and Oren says aliens make everything better. [laughter]
Plus I think that the two main characters have a marriage that’s kind of on the fritz and they, I think we just had a podcast on romances. They kind of have a coming back together that I think is done pretty well. I also just like Ed Harris as an actor.
I think he does a great job in that. Yeah, it’s fun. It’s very cool. It’s very creepy and it’s very beautiful in some parts, it has all the parts. It has underwater creatures, it has broken tech that is leaky and dangerous. There’s submarines, there’s underwater vessels, there’s diving suits. And very fun things. So I cannot recommend it enough, it is the underwater adventure.
Chris: That sounds great. I really like the idea of having an alien landing that happens underwater and then the humans have to go and try to find it. And then they spend their entire time being like “is this an alien? Or is this a weird underwater creature we haven’t seen yet?”
Wes: Yeah, exactly.
Oren: It said an alien or a deep sea fangly fish.
Wes: There are cool things that they talk about in that movie, and this is yet another reason why it’s a hostile alien environment, right? I mean, sure, if you’re in outer space, you know, all kinds of terrible things can happen to you, but just going deep underwater means that you cannot come back up for awhile, right? Our body, our bodies cannot tolerate it. It’s called the bends, and it’s where, is it nitrogen? Or something? [Oren agreeing] I think your blood boils and it kills you. That’s the thing I remember very much from The Abyss, one of the first things that happens is this new crew is going down and she’s tells them it takes three weeks to reacclimatize, just like “oh my gosh.”
When they go back up, they’re going to be stuck in their little exploratory vessel for three weeks, just so they can get out of the ocean. So, yeah, there’s all kinds of hostile things going on that isn’t in outer space, so you can go do your space walk and come back into your spaceship and enter and exit atmospheres and be fine. Not underwater.
Oren: Yeah. I’m actually a fan of any kind of story that involves having to go and get something that if it was on land would be super easy. It’s like “hey, we need to go to those ruins and get a stone from them.” It’s like “all right, but those ruins are 500 feet under water.” So it’s like “oh man, now everything’s way harder.”
It just makes everything more challenging and gives you the opportunity to introduce weird creepy, scary things. If you’re going to read a Lovecraft story, one of the better ones is called The Temple.
It’s about this German World War I submarine that is damaged and drifts into deeper and deeper water. It’s one of his better stories and it’s really creepy and weird, and it uses the environment to its full capacity. Kind of opposite of Aquaman.
Wes: A fun thing about that Lovecraft story is it’s one of the few ones where he actually attempts to bring a little levity into his stories.
Oren: Really?
Wes: I’ve read it several times and the way the narrator, who is German, speaks and the ideas he expresses, I think Lovecraft is making fun of Germans during that time. Because of how pompous he is and he looks down on the Rhinelander and it’s like “my German will”, even though there’s an irony going on because he’s not upholding these Prussian values, right? So I think it’s one of the few things where Lovecraft is kind of making fun of somebody instead of just embracing horror, and then on occasion racism.
Oren: Look, look, I mean, at least in this case when Lovecraft is stereotyping someone, it’s like a privileged pressure, right? [laughter] It’s, you know, it’s not a person of color. It’s not even a group of European immigrants that were particularly discriminated against, right. It’s an old world Prussian aristocrat, and like “yeah, go ahead and make fun of that guy, whatever.”
Wes: Plus he makes dolphins creepy in that story as well [Oren agreeing]. Yeah, there are creepy dolphins.
Oren: Weird, creepy, creepy dolphins.
Chris: They’re also creepy dolphins in Area X, actually. [agreement] Area X under the water in the deep sea would be really sweet. [agreement]
Oren: Well, if I may engage in a bit of self-promotion, I do happen to have produced a role-playing game called Rising Tide, which is about weird Area X type things happening on the ocean. And by default, you are on a surface ship. But you know, you could go underwater, I’m just saying, you could get to go down underwater.
Chris: Isn’t there a shark cage item in there?
Oren: There’s a sealed laboratory type item where it’s airtight so you can go underwater with it. There is a submarine though, one of the advanced loop pieces is a little submersible you can get, so just go have fun with it.
Chris: There’s some items in the game that are specifically for going underwater.
Oren: And I’ve used that when I was running Rising Tide, be like “hey guys, you enjoyed the surface world, but now get to see what things are like under the sea…”
Wes: Under the sea. If you’re looking for a few other underwater adventures, you can check out 20,000 Leagues Under the Sea. You know, really the first underwater story, it’s fine. Another one that I remember seeing the movie, I didn’t read the book, is Fear.
Chris: I didn’t even know that had a book.
Wes: Yeah, it’s Michael Crighton, he wrote the book and then they adapt it, because you know, people love adapting Michael Creighton books.
Chris: That one was a thriller I think. It was okay.
Wes: It was almost more like an outer space movie than an underwater movie to me. But I do like the creepy scene where the character is reading 20,000 Leagues Under the Sea, and then, well, minor spoilers here, but there’s kind of a lot of questionable reality because these people acquire this power from this sphere and he’s reading 20,000 Leagues Under the Sea. And then it’s kind of unclear whether or not their vessel is being attacked by a massive squid. That was actually pretty well done. That and The Abyss and I mean, Finding Nemo is great.
Chris: Yeah. I mean, I suppose you could watch The Little Mermaid. There’s not very many stories.
Wes: No, there’s really not. Yeah. You can actually check out a Wikipedia page. It’s underwater stories and it’s an alphabetical listing of them. There’s like 20. And I haven’t heard of almost all of them. It’s just a very limited genre. So storytellers go out there and give us more cool underwater adventure. We need it.
Oren: All right, well, on that note, we are out of time so I’m going to call this episode to it’s watery grave… [laughter] Before we go, I’m gonna give a quick thanks to two of our patrons. First Kathy Ferguson, who is a professor of political theory in Star Trek. And Ayman Jaber who is an urban fantasy writer and a connoisseur of Marvel. Otherwise if anything we said piqued your interests you can leave a comment on the website at mythcreants.com and we will talk to you next week.
[closing credits and music]
P.S. Our bills are paid by our wonderful patrons. Could you chip in?
Fore the love of god, don’t read Low!
They lure you in with a beautiful charming family about to initiate their two daughters into the families warrior traditions, and set out to solve an exciting mystery and also embark on a quest that will yield the worlds salvation. Then they extract your soul one horrible, depressing page at a time.
It doesn’t help that if you like your spec-fic on the firmer side the whole universe is utterly infuriating.
Rick Remender, the writer, specifically wrote Low to be about hope
It’s a good story, but hopeful it ain’t!
Aquaman features Jason Momoa riding Julie Andrews into battle. I’ll forgive it anything :).
That would be awesome in the stage production.
In the Underwater Rules? thread on reddit RPGdesign I made a comment which included the following:
A quick search of “Underwater” on drivethrurpg.com gives only a handful of usable games
Assuming you don’t drown, the main issues of underwater include:
three dimensional movement, including things not falling when dropped and people not falling when knocked out or killed (non-buoyant things sink slowly and buoyant thing float up)
weakened and slowed attacks and actions, especially if you wear heavy clothing, and most distance weapons won’t work, particularly modern guns unless specially designed, like a speargun (your roll twice and take the worst might work, but it probably would be easier just to have a penalty to hit and halve movement and damage)
no fire, including fireball, except for certain magical fires
electricity affects everyone in the immediate area
lowered visibility, worse as you go farther down, and no visibility for a normal human w/out goggles
cold and pressure increase as you go down
certain items get ruined from water (steel rusts, paper gets soggy, leather shrinks)
trying to drink a potion underwater is… not recommended
normal humans can’t hear or smell underwater, but native critters can hear and smell better than surface critters ( sound travels farther and faster so a sonic blast is DEADLY, and although frequently exaggerated, a shark can smell blood 1200 to 1500 feet away, and some fish have electroreceptors that can detect electricity in their prey’s muscles)
humans can’t talk under water
Very few crabs sing w/ a Jamaican accent
As I said, most of these are obvious, but they are something to consider before the game starts. Otherwise the guy in heavy armor who has a ring of Burning Hands and several Cure Wounds Potions might get annoyed…
lowered visibility, worse as you go farther down, and no visibility for a normal human w/out goggles
Depending on how you decide infravision/darkvision works – despite the former name, it’s often treates as more magical than seeing in IR – that may suffer the same effect.
trying to drink a potion underwater is… not recommended
Unguents are probably going to be inefficient too.
When you mentioned underwater aliens I immediately thought of Animorphs. It’s been a long time since I read it, but if memory serves an alien ship crash-lands in the ocean and the main characters have to morph into whales to contend with the pressure. It’s very tense because there’s a two-hour time limit for morphing and of course if they try to de-morph at the bottom (or even just not near the top) they’ll die. I can’t remember if it’s the same book or another, but the villain aliens (Yeerks) also have an underwater base.
I believe the crash-landing ship book is this one: https://animorphsforum.com/ebooks/4/ The site hosts all of the out-of-print series, with the author’s blessing https://twitter.com/kaaauthor/status/1086782062898675714
Behold, a transcript!
What? No love for Subnautica? You have Bioshock, but not a game about surviving in the water on an alien planet?