Everything About Fiction You Never Wanted to Know.

You have suffered minor head trauma. This is considered an optimal outcome.
This PDA has now rebooted in emergency mode with one directive: to keep you alive on an alien world.
Please refer to the databank for detailed survival advice. Good luck.

Copper is an essential component of all powered equipment. Your probability of survival has just increased to: unlikely, but plausible.

Subnautica is a Wide Open Sandbox Survival Horror game from Unknown Worlds Entertainment, released on Steam in Spring of 2018 after a long (and very popular) beta release. In it you take the role of the nameless survivor of a crashed starship[1], trying to survive on an alien world that is almost entirely ocean. Stranded on Planet 4546B with almost nothing in your metaphorical pockets and only a badly damaged Escape Pod for shelter, you must scavenge the ocean floor for both salvage and natural resources while ensuring you have food and fresh water to keep you alive. Along the way you learn the history of Planet 4546B both recent and ancient, encounter the remains of a ancient alien research facility... and are infected with a deadly disease.

And then you discover that the ancient alien facility is anything but shut down -- and is enforcing a quarantine of the planet. Violently. Getting off the planet and going home has suddenly become quite a bit harder...

Subnautica is available for both the PC and Xbox.

Subnautica: Below Zero, an expansion/sequel set in Planet 4546B's polar regions, had a beta release in January 2019, and was given a formal release in early 2021.

Tropes used in Subnautica include:
  • Alien Sky: Planet 4546B has two moons (one smallish and more or less stationary, one freakin' huge and in constant motion), and a smallish white sun. The night sky is more heavily star-strewn than ours, and the large moon eclipses the sun on a regular basis. Oh, and the sun rises in the northeast, according to in-game compasses, and sets in the southwest.
  • Almost Out of Oxygen: This is a constant threat, as you have to spend much of your time underwater collecting salvage and natural resources -- and at first all you have is your ability to hold your breath. Eventually you can build diving equipment, but all but the best simply extend how long it takes you to run out of oxygen.
  • Always Check Behind the Chair: When you visit wrecks -- especially when you explore the Aurora -- make sure you have a propulsion or repulsion gun on you. Because you never know what you might find underneath a pile of wreckage you can't otherwise move. Similarly, have plenty of fire extinguishers handy when you visit the Aurora -- several fires, particularly near the entrance to the interior, have loot sitting inside them.
  • Ambiguously Brown: The player character.
  • Apocalyptic Log: You're constantly finding PDAs with recorded log entries and personal notes, among other things -- and more than a few are the final despairing messages of doomed colonists or frantic pleas for help from your fellow refugees from the Aurora.
  • Artificial Intelligence: Your PDA has one, but while it is occasionally snarky, it's not a conversationalist. It mostly reminds you about basic needs, offers dubious advice for coping with your castaway status, decrypts records and manages your data, as well as occasionally spouting Alterra Corporation policies.
  • Atlantis Is Boring: Thoroughly averted. The most boring part of this game is the endless ocean surface. Beneath the surface is where things are interesting.
  • Awesome but Impractical: Killing a Leviathan will make you feel like a badass, but there's no real benefit to doing so. They're ridiculously durable, meaning that it takes forever to kill one and there's no real reward for doing so. While it can make exploring certain biomes safer, the effort needed to kill them isn't worth it since simply dodging them saves time, resources, and is far more convenient.
  • Big Freaking Gun: So big you will not realize it's a gun until it fires.
  • Brick Joke: You are the sole survivor of the crash landing of a starship owned by a company called Alterra. One of the many announcements made by your PDA's AI very early in the game is a notice that you will have to reimburse Alterra for all the materiel you salvage and the tools and equipment you use in the process of getting off the ocean planet on which you are stranded. Some thirty or so hours of play later, after you've built a starship and successfully rescued yourself, and after the ending credits finish rolling, the same computer voice welcomes you back to Alterra and blandly informs you that you are required to pay your tab of one trillion credits before they'll let you land. Hard Cut to black.
  • Bug-Out: The game begins with a panicked dash by the player character into an Escape Pod when the starship he is on suffers a catastrophe and he must flee for his life.
  • Call a Rabbit a Smeerp: Averted. The lifeforms throughout the game are unique and well-thought-out, and only bear resemblances to Earth creatures when such is imposed by occupying similar ecological niches.
  • Convection, Schmonvection: A particularly Egregious example can be found in the "Lava Lakes" biome -- where open pools of lava exist in perfect harmony with water cool enough to swim through safely, deep below both the ground and the surface of the ocean. Said lava neither cools to solid rock nor flash-heats the sea water to steam.
  • Cutscene: The end-of-game return to Alterra works very much like one, except there's no "cut", and the credits run during it.
  • Deadpan Snarker: Your PDA does have its moments -- see the page quotes for two examples.
  • Diegetic Interface: Subnautica is an interesting case. The default interface appears not to be diegetic, but once you start building advanced personal diving suits and their subsystems, their HUD elements add to the ones already on the screen, suggesting the majority of the game interface actually reflects in-game systems.
  • Downer Beginning: The game starts with the starship you're on crashing on a deserted planet, with you all alone in an Escape Pod.
  • Easier Than Easy: "Creative" mode, in which you have all the blueprints in the game, don't have to harvest and can't run out of resources, don't need oxygen, food or water, and cannot be hurt by any means. Your vehicles are also apparently immune to depth pressure and damage from collision and sea creatures. Many events from the game's plot -- both scripted and not -- still take place, but there's really no consequence (or point) to them.
  • Escape Pod: Subnautica begins with a Cutscene of you boarding an escape pod and ejecting from a ship which promptly explodes, after which you are knocked out by flying debris. When you awaken, you are still in the (damaged and burning) pod, which becomes your shelter and base for the early part of the game.
  • Event-Driven Clock: Has a day-night cycle that runs independent of your actions, and which governs when certain game-relevant events happen -- although the "timers" on some of these are only started when you have a chance to listen to certain radio messages.
  • Event Flag: The most obvious Event Flags in Subnautica are those set by listening to radio messages. Several key game events will only happen if you hear the correct precursor messages.
  • Everybody's Dead, Dave: Yours is not the only Escape Pod which made it off the Aurora, and once you've built a radio you'll get calls for help and coordinates for other pods. But by the time you get to them, there are no survivors left.
    • And eventually you discover you're not the first human to land here, either -- there are abandoned habitats from earlier attempts at colonizing the planet, of which no one survived.
  • Expositron 9000: Your PDA's AI provides background from its own databanks as well as from your scanner traces and from PDAs scavenged from wrecks and abandoned habitats, and is your interface for all in-game information.
  • Fake Video Camera View: Once you have built a scanner room, you can send out camera drones; when you access them, you get a view with a cross-hairs-like overlay among other details.
  • Featureless Protagonist: Literally. Unlocking the camera reveals that, despite casting a perfectly normal shadow, your character model has no head. He is male, though. And your shadow reveals a truly ridiculous pompadour hairstyle.
  • Fast Forward Mechanic: If you have managed to construct a bed, you can sleep any time you are not completely rested. It's hard to say because there's no in-game clock, but it appears to advance you about eight hours.
  • Fetch Quest: There are a number of these, both explicit and implicit. At the very start of the game, your very survival depends on finding fragments from the crashed ship from which your Escape Pod ejected to use as blueprints for equipment you need, so you assign yourself "quests" to find the stuff you want. Once you've been able to repair your radio, you will receive messages from other survivors asking you to come to their locations for various reasons; by the time you get to them no one is ever left, but they've left behind useful information and/or gear. Similarly, once you find the records of previous settlers on the planet, following up on their leads gives you more information and equipment and ultimately a way into the end game. There are also any number of game events which are triggered when you have reached the right physical location in the game or have built the right piece of equipment.
  • First-Person Ghost: You can see quite a bit of your body -- enough to know you have one. And in bright sunshine you cast a complete shadow. (However, if you enable a cheat that lets you move the camera away from your first-person point of view, you will discover that while you have a body, you are distinctly lacking a head -- regardless of that shadow and its outrageous pompadour hairstyle.)
  • Flying Seafood Special: Peepers can sometimes be seen leaping from the water in the Safe Shallows around your Escape Pod -- and Leviathans can be seen breaching not unlike whales near the engines of the crashed Aurora and other deep-water areas.
  • Force Field Door: It seems like every alien base has at least one doorway blocked by a forcefield, requiring you to find a "tablet" of the appropriate color to open it.
  • God Mode: "Creative" Mode, where you don't need oxygen, food or water, nothing can harm you, and you have all blueprints and can build anything without the need to gather/craft resources first. (And all of these attributes can be toggled with the appropriate console commands in the game's other modes, but some if not all will force an automatic switch to Creative.)
  • The Great Repair: This is key to the plot right from the first minutes of play -- your Escape Pod was damaged during your crash landing, and fixing its broken subsystems is necessary to progress further in the game. Repairs are in fact a key part of surviving in Subnautica, including repairs to the crashed ship to keep it from dumping radiation into the sea you have to live in. Averted in the end game; while you have to assemble an escape rocket, you actually build it entirely from scratch rather than gather the Aurora‍'‍s broken parts and fix them.
  • Green Hill Zone: The Safe Shallows. The game's starting zone, where your Escape Pod ended up, it's shallow and reasonably safe, and has most of the basic resources you need to get a foothold on surviving.
  • Grimy Water: The toxic Underground River, which instead of being brown has a Sickly Green Glow.
  • Hell Is That Noise: The howls/roars of leviathans. If they suddenly get very loud, very fast... well, you may be out of luck.
  • Heroic Mime: Justified -- you're all alone on the planet. Who are you going to talk to, the fish?
  • In-Universe Game Clock: The game has a continuous day-night cycle that runs 20 minutes from midnight to midnight, with a bit more than 15 minutes of daylight and a bit less than 5 minutes of night. This overlaps with an Internal Game Clock as your total days on Planet 4546B are tracked, and many events in the game are on timers that start either with the game, or after you visit some point or perform some task.
  • Jump Physics: Almost completely missing from the game. You have virtually no ability to jump upwards when you are on land or another dry surface (pressing the control that triggers a jump results in a truly pathetic little hop, which is only useful for helping you get up steep slopes). You can jump down, but it's less a true jump than an aimed plummet, and beyond a certain height your arrival turns from a safe landing to a damaging fall.
  • Jump Scare: There aren't any scripted examples, but Reaper and Ghost Leviathans have a frightening tendency to pull these off. You can be swimming around in open water, minding your own business, only to have one of these massive serpentine monstrosities lunge at you from out of nowhere and roar/scream in your face.
  • Kaiju: The (thankfully) dead Gargantuan Leviathan, whose skeleton measures out nearly a mile long. As scary as the living Leviathans are, imagine coming face to face with that thing.
  • Kilroy Was Here: The game lets you leave a gift and a message for a future player of another instance of the game.
  • Ladder Physics: Subnautica uses ladders as transitions between different floor levels. Once you choose to use a ladder in either direction, you usually get a brief animation of the climb and then find yourself at your destination. You cannot stop in the middle of the climb nor can you use any tool or weapon in hand. Amusingly, all ladders take about the same time to climb, regardless of their length.
  • The Lava Caves of New York: The "Lava Lakes" biome -- a giant undersea cave whose floor is wall-to-wall lava, with the lava neither cooling to a solid crust nor causing the water touching it to flash into steam.
  • Loads and Loads of Loading: The more extensively you build, the longer the game takes to load. If you've gone hogwild in Creative Mode, you can go make lunch while the game loads.
  • Magic Tool: The Repair Tool, which fixes almost anything broken in the game, as long as it hasn't been reduced to shattered and scattered parts, by realigning its component atoms into the structure they should be in.
  • Monster Is a Mommy: The Sea Emperor. She's been holding on this long in hopes of finding someone she can communicate with and convince to synthesize the biochemicals needed to hatch her offspring. As soon as she knows her children have made it to the open sea, she lets herself die.
  • Mook Bouncer: The Warpers.
  • No Recycling: Averted, and actually a useful tactic. Fragments of your crashed starship can be salvaged and rendered into raw materials for new construction. Identifiable pieces of equipment can also be scanned to generate blueprints from which you can construct working versions, and after that, scanning future pieces will render them down into raw materials, too. You can also deconstruct almost anything you built, and get the raw materials used back.
  • Noodle Incident: The reason why the only weapon you can acquire plans for is a knife because, according to your PDA's AI:

"Weapons were removed from lifepod fabricators following the massacre on Obraxis Prime.
The knife remains the only exception."

  • Oh Crap: The first time a Leviathan lunges out of the darkness at you. And the second. And the third. And... ah, hell, every time a Leviathan lunges out of the darkness at you.
    • The arrival -- and destruction -- of the Sunbeam.
  • Oxygen Meter: The game has one that initially reflects your ability to hold your breath, then as you build better and better air tanks for yourself, their capacity.
  • Oxygenated Underwater Bubbles: Brain coral emit bubbles of breathable air that somehow automatically refill your air tanks if you're wearing any, or just help you hold your breath longer if you aren't.
  • Precursors: Long gone from the planet, but they certainly left enough bases and random junk around for you to explore. You even manage to decode a little of their computer system to find out why they were there.
  • Scripted Event: The arrival of the Sunbeam is a scripted sequence that starts about a month after your arrival on Planet 4546B, but it's dependent upon you actually going to your radio and listening to a couple of messages; if you never listen to the messages, they never actually try to land on the planet.
    • The various encounters with the Sea Emperor are scripted to fire when you reach certain specific locations and/or meet other requirements.
  • Sea Monster: Reaper, Sea Dragon, and Ghost Leviathans are massive, ferocious beasts that are among the most dangerous creatures you'll encounter. The Sea Emperor Leviathan is even bigger and scarier-looking than them, but she's friendly and will never attack you.
  • Selective Gravity: Amusingly omnipresent in the game -- you, your dropped possessions, and the occasional submarine are the only things that will reliably fall when unsupported. It is possible to construct an entire base in mid-air, with no support whatsoever, and it will just hang there. No, scratch that -- it is possible to create a network of corridors and rooms spanning the entire playable area of the game in mid-air, with no support whatsoever.
  • Single-Biome Planet: Utterly averted by Planet 4546B. Kind of -- you're lucky enough to have crash landed in a volcanic caldera more than a mile across, which is home to at least a dozen different underwater environments explicitly identified as "biomes". However, it's strongly implied that the variety of these biomes and the creatures that inhabit them is the exception rather than the rule for the rest of the planet, which appears from space to be a near-complete water world, except for its polar areas. And the Precursor records you eventually find suggest that the creatures inhabiting the caldera (and the caves beneath it) are doomed to eventual extinction.
    • Subnautica: Below Zero, the sequel/expansion released in January 2019, reveals that the world has equally lush biomes in its polar regions.
  • The Sleepless: One of the few bodily needs you don't have to take care of is sleep -- in fact, you can't sleep until you've figured out how to build a bed. And even when you have a bed, you never need to use it.
  • Soft Water: You can dive into the water from practically any height with no ill effects. Given the "terrain" of the game, though, you need to build yourself something to leap off of if you want to test this for heights above a few dozen meters.
  • Space Compression: Subnautica has a curious variation. The volcanic caldera in which you've landed (and which is almost the only part of the water world you're on which has sea floor anywhere near the surface) is only two kilometers or so across, which you can travel in reasonably realistic times. However, in that small area are something around a dozen different biomes ranging from warm shallows to underground caverns filled with lava, each with its own set of distinctive flora and fauna.
  • Super Drowning Skills: Implemented realistically. You start out able to hold your breath a short but reasonable time as you gather salvage from your crashed starship in the shallows in which your Escape Pod landed. Eventually you are able to build several increasingly more effective sets of diving gear, but they all have a limit to how long you can remain underwater before needing to recharge your oxygen supply; ignoring this limit results in dying and respawning without anything interesting you may have recently stuck in your inventory.
  • Super Not-Drowning Skills: Subnautica‍'‍s "Creative" mode disables all the various "survival" gauges that play a major part of the "default" game -- including your need for oxygen, allowing you swim indefinitely at any depth.
  • Surveillance Drone: The scanner room comes with two camera drones and a fabricator which lets you build more. If you build more than one scanner room, you have access to all your drones in each -- although the signal starts getting fuzzy and may turn into nothing but static if the drone is too far away.
  • Survival Horror: Subnautica is frequently described as "survival horror", but it leans very heavily on the "survival" side of the equation, with the "horror" aspect provided by the large ocean predators that lurk only in certain parts of the game, making scary noises and then suddenly lunging at you out of the dark depths.
  • Synchronized Swarming: Realistic schools of fish are found all over. Curiously, one game option allows you to turn off their Synchronized Swarming.
  • Take Your Time: Shortly after your landing, you are infected with an alien disease which allegedly is going to kill you Real Soon Now. Oddly though, you never show any symptoms other than glowing green spots on your hands, and you can spend literally months in-game poking around every nook and cranny on the sea bed without feeling the least bit inclined to, you know, keel over and die.
  • Techno Wreckage: The Aurora scattered massive chunks of itself all over the ocean floor. Exploring them -- and the burning starship itself -- is necessary for your long-term survival.
  • Terrain Sculpting: The Terraformer tool allowed this before it was Dummied Out. (But not completely; the correct cheat developer code will add it to your inventory.) Even so, it's still subverted, as the changes you make with it will not persist between game sessions. If you use the Terraformer to widen a magma vent so you can install thermal plants all around it, then save and exit the game, the next time you play you will find all the stone you excavated has returned -- and your thermal plants are now embedded in it (and still working just fine).
  • Traveling Landmass: Simultaneously expressed and averted by the Floating Island. The island genuinely floats, having no connection to the seabed below it and lifted by the buoyancy of the huge, ancient "floater" creatures adhering to its underside. Its aversion comes from the fact that it is absolutely motionless: it never moves from its established location on the world map; it doesn't even bob in the water. It is perhaps the most rock-solid floating object you will ever encounter.
  • Tube Travel: This is how vertical connections in bases work -- you click "climb up ladder" or "climb down ladder", and suddenly you're at the other end, no matter how long a climb it is.
  • Underwater Base: Building one, while not exactly required, is extremely useful and directly makes it possible to complete the endgame. The flexibility of the base-building system makes it almost a minigame in and of itself, especially when combined with the game's rather selective implementation of gravity; while it was still in beta there were already contests for the most amazing/interesting bases, and many players seem to use the Creative mode of the game solely to see how extravagant or elaborate a base they can build.
  • Underwater Ruins: The sea floor is littered with fragments of your crashed starship, many of them large enough to enter and explore (and doing so almost always profits you in terms of knowledge and/or supplies). There are also abandoned habitats from earlier settlers which you can find and explore. The completely functional Precursor installations obviously don't count for this trope.
  • Waterfall Into the Abyss: The "Lost River" biome -- an undersea cave system -- features an unusual variant, in which currents of poisonous green and blue liquids flow as rivers and waterfalls separate from the water around them, with some falls that plummet through the sea floor to unknown depths below. This is, surprisingly, Truth in Television, as differences in dissolved solids can cause differences in density that permit this kind of behavior.
  • Wave Motion Gun: The alien "building", which is powerful enough to one-shot a starship. It's strongly implied that the Aurora crashed because it got too close to Planet 4546B and tripped the sensors that fire it.
  • Wide Open Sandbox: While Subnautica is "officially" considered a Survival Horror game (mainly because of the scary Sea Monsters that lunge out at you from the depths if you're careless), it meets all the criteria for a Wide Open Sandbox, what with all the biomes, creatures, and Precursor stuff laying around. Even though you're supposedly infected with an inevitably-fatal disease, it doesn't seem about to kill you any time soon and you can explore to your heart's content.
  • World Map: Utterly averted. You get a compass -- if you can find enough scraps from which to generate a blueprint for one -- and that's it for tools to help you navigate your way around the two-kilometer-square caldera in which your starship crashed. Made worse by the wide and varied biomes under the ocean that outside of the shallows are undetectable from the surface, and the fact that you have exactly four landmarks above the surface (your escape pod, the wreck of your starship, and two islands). Your best bet is to get a map made by other players off the Net.

Detecting multiple leviathan class lifeforms in the region. Are you certain whatever you're doing is worth it?

  1. Later game materials reveal his name is Ryley Robinson.