Video Game / Rain World

What fate a slugcat?

Rain World is a 2017 2D Speculative Biology-themed exploration game developed since 2011 by Videocult and published by [adult swim] for PC (via Steam), PS4 and Linux. It is set in an abandoned industrial environment ravaged by a shattered ecosystem.

Bone-crushingly intense rains pound the surface, making life as we know it almost impossible. The creatures in this world hibernate most of the time, but in the few brief dry periods, they go out in search of food.

You are a nomadic slugcat, both predator and prey in this land. You must hunt enough food to survive another cycle of hibernation. Other — bigger — creatures have the same plan. The goal of the game is to reunite with your family.

Gameplay can be described as a Cinematic Platform Game with Survival Horror elements in a Metroidvania style map. The main gimmick is the ecosystem of the world, which is highly reactive and nonscripted. For starters, the game is segmented into "dry seasons" when the titular rain stops, forcing the player to return to shelter with enough food in stock to properly hibernate and survive. In addition, the game is further divided up into nonlinear "regions" rather than one cohesive map. To move forward, the player must accumulate enough "Karma" by successfully surviving regions enough times, and in doing so can move on. Graphically, the game's standout feature is that almost all creatures, including the slugcats themselves, operate on a system of procedural animation: rather than having premade animations, the game's physics engine determines the motion of every creature in real time and the character models respond accordingly.

An Expansion Pack titled Rain World: Downpour was released on January 19th, 2023, which adds more areas and five new playable characters, as well as local co-op and randomizer modes.

---

The game provides examples of:

• Acid Pool: In Spearmaster's and Artificer's time, the Garbage Wastes has pools of deadly green acid, many situated in buildings only found at that time.
• Advanced Movement Technique:
  • Turning around while running gives Slugcat a slight backwards boost.
    • Jumping while suddenly turning around makes Slugcat backflip and jump higher. This lets the Rivulet leap especially high.
    • Repeatedly jumping after turning around exploits both the speed boost and the fact that horizontal speed isn't lost while airborne, allowing Slugcat to traverse flat ground faster.
  • Pressing down and jump while walking makes Slugcat slide. A mid-slide jump can be performed to move farther and faster, particularly as the Gourmand.
  • Pressing down and forward lets Slugcat roll after falling to the ground from an angle. This prevents it from being stunned after a drop.
    • Pouncing can be done instantly by jumping from a roll. The pounce is longer after shorter rolls, and higher after longer ones.
  • Throwing an object mid-air slightly boosts Slugcat in the throwing direction, allowing it to jump slightly farther than normal.
  • Jumping on a ledge makes Slugcat climb onto it. This can be done after a pounce.
  • Pressing jump while moving backwards in a tunnel makes Slugcat turn around, to move in the opposite direction faster.
  • Pressing jump while moving forward in a tunnel gives Slugcat a small boost before they slightly fall.
  • Jump-boosting in water uses up a lot of breath, but allows for sharp turns that allow Slugcat to traverse underwater corners or evade aquatic lizards.
    • Boosting at a slight angle below the surface of water allows Slugcat to swim fast, whilst exploiting its buoyancy to maintain its breath.
  • Slight snakelike turns allow Slugcat to traverse underwater pipes faster.
  • Pressing against a wall in zero-gravity allows Slugcat to crawl on it slowly, or even round corners.
  • Reorienting Slugcat to throw its tail around will boost it in the tail's direction in zero-gravity.
• After the End: The precursors are nowhere to be found, monsters are roaming the place, and vast industrial architecture is decaying around you, but there's a strange beauty to it all.
• A.I. Is a Crapshoot: Five Pebbles drained massive amounts of water from the region/continent/planet in order to sustain the facility he's housed in, which causes the deadly rains you encounter, since the water evaporates and gets released into the atmosphere, said drainage nearly killed Big Sister Moon.
• Anachronic Order: Each slugcats' journey is set in a different time from one another. You'll have Monk and Survivor unlocked first, then you'll unlock Hunter, whose story takes place before the previous two. The Downpour DLC also adds characters whose story takes place before the Hunter, but also after the Monk. The complete order is as follows: Spearmaster -> Artificer -> Hunter -> Gourmand -> Survivor -> Monk -> Rivulet -> Saint. ??? is exempt from this timeline, since their campaign is designed to be exceptionally difficult regardless of its logical sense within the story.
• Antepiece:
  • If you follow the Overseer (the small yellow worm), the game makes extensive use of these to teach you essential survival skills.
    • The first area doesn't have any rain come until you're right next to a shelter, so you can Take Your Time learning the Slugcat's controls, how to hunt bat-flies, and eat fruit to survive.
    • When you are introduced to the rain, you are right next to a shelter, so you can immediately learn where you should go when you can see the earthquake that indicates the imminent rain. In addition, a curious player can witness the effects of the rain both outside and inside (crushing rain and flooding respectively) with relative safety.
    • To teach you how Scavengers value pearls, the first 2 times you need them (getting past a Scavenger Toll and buying a lantern respectively), you are able to find a free pearl on the way.
    • Your first foray through the Outskirts inevitably leads you to your first predator, the Lizard. Conveniently, there are also many scattered poles you can climb and crawling spaces you can squeeze through, which shows evading creatures is as much a strategy as fighting them head-on.
    • Through the intended path in the Shorelines, you'll find a beached Jetfish, with the game nudging you to carry it to sea, where you'll find that you can ride the Jetfish in an empty environment to let you come to grips with its controls, as well as cluing you in that not all creatures are hostile and can be beneficial to you.
• Anti-Frustration Features:
  • The Overseer that follows you around will periodically point toward the path you need to take to progress the story, or toward the closest safe room should you be a few minutes away from the rain, unless you're low on food in which case it'll try to lead you to some. Following it also takes you on the easiest path through the game.
  • The game keeps a fairly accurate map as you play, and places blue blips where food might be whenever you spawn into a cycle.
  • You are never more than four to five rooms away from a shelter at any given time. As mentioned above, the observer will point you towards the nearest shelter if rain is about to come.
  • If you can get to the Depths with maximum Karma unlocked, but are currently not at maximum Karma (something likely to happen considering the hell that is the Filtration System), the Guardians will let you pass and ascend anyway. This makes it so that entering the Depths, which is the Point of No Return, does not result in an Unintentionally Unwinnable scenario for the player.
  • If you play as the Monk in Arena mode, non-Cyan lizards do not attack you without provocation. This allows lizards' high-reputation states to be freely simulated.
  • Predators are able to enter your shelter before the game transitions to the hibernation screen. Should that happen, the beginning of the next cycle will give you a grace period to leave the shelter before any creatures inside turn hostile.
  • The Remix update introduces a vanilla mod that adds variable options, from bug fixes to QoL to significant balance changes, to allow you to make the game as easy or challenging as you desire, making Rain World's brutal difficulty much more manageable for those initially scared off by it. This also does not affect earning achievements, giving players the best experience with no drawbacks.
  • Because Scavengers are invariably hostile to the Artificer, she cannot safely trade with them for a lantern. However, despite not being an explosive, she can convert a food pip and a flashbang into said lantern.
  • Artificer also needs to kill scavengers to use their bodies to pass through karma gates. To alleviate this, areas in other campaigns that don't have natural-spawning scavengers (The Exterior, Shoreline, and Outskirts outside the toll leading to Farm Arrays) will have scavengers roaming around early in the timeline (forming the occasional kill squad), to make things easier.
  • Early campaigns make Drainage System and the path from Subterranean to Waterfront Facility into Tide Levels that gives windows of time to move through the air in lower parts of rooms. This makes those areas possible for Artificer to traverse at all, since she dies upon staying underwater for five seconds.
  • The Gourmand moves slowly outside flat ground, and its breath meter is drained if it throws a spear, making water more dangerous for it. To compensate, Shoreline has zero Leviathans in its playthrough.
  • The Rivulet's campaign is based around travelling through areas at high speeds in short amounts of time. Just to facilitate this playstyle, there are no Miros Birds to hide from in the Rot-infested Memory Crypts.
• Apocalypse How: Class 3a, originally intended to be Class 5 or 6. As part of their belief that all living things were suffering in the Great Cycle of reincarnation, the Ancient civilization strived to find a way out; to allow all living beings to ascend. Their attempts ultimately failed, and in the end they all left the world and their creations behind in their own global ascension via the old flawed method of Void Fluid.
• Artificial Brilliance:
  • Most creatures will start to become frightened and will flee when near death, albeit slowly due to being crippled.
  • Lizards have a "rivalry system" of sorts whereby two lizards near each other will gradually get more and more annoyed with each other and eventually will fight to assert dominance. The differing lizard types even have different rates of getting annoyed, with green lizards being by far the most territorial, even being the only lizard type who will stand and fight a vulture.
  • Yellow lizards are very good at surrounding you and seem to even have a "leader" in every pack, frightening said leader off can cause the whole pack to lose their telepathic cohesion.
  • Vultures can be unmasked, and doing so will cause them to aggressively stalk and hunt you over the next few cycles, unlike other enemies who won't show up again for the most part after a cycle or two. Unmasked vultures are additionally "bullied" by masked vultures. Additionally, the mask can be worn by the slugcat, and this will garner the respect of the Scavengers and will frighten most lizards away.
  • The number of Enemy Mine situations occurring in the game can actually lead to you befriending otherwise hostile creatures, along with feeding them. They'll even follow you around and fight with you, even sleeping in shelters with the slugcat.
  • The tentacled blob-things called the Rot are very good at fishing through tunnels with their tentacles to try and snatch the slugcat, though they're not quite intelligent enough to stop doing so after you've speared said tentacles enough times.
• Artificial Gravity: The inside of Iterators are zero-gravity environments, which periodically stop functioning in some areas.
• Artificial Intelligence: There exist several supercomputers called Iterators. You can meet two of them, though it won't be easy to get to their respective facilities.
• Artificial Stupidity:
  • Especially prior to Downpour, Rain Deer often seem to forget how to walk, trip and fall, and are difficult to ride.
  • Miros Birds often get stuck on corners, and are unable to free themselves. This can prevent you from passing through them safely.
• Ascend to a Higher Plane of Existence: The Echoes of the Ancients you meet are a result of botched ascendance procedure, members of the civilization whose ruins the game takes place in. Apparently, the members of the ruined civilization attempted to break the cycle of reincarnation by ascending/transcending material existence, using something called Void Fluid. However, if a person had too many vices, or was especially arrogant, it would get stuck between this world and the next. Your ultimate goal is to follow in their footsteps after maxing out your karma - strange creatures called guardians will chase you away once you reach the end of the game otherwise.
• A World Half Full: A downplayed and very long-winded version: the three most combative campaigns are first in the timeline, whereas the nature-taming Monk, fleeting Rivulet, and pacifistic Saint are last. That means that over time, fighting in the game world becomes less practical, and ascension becomes more accessible to wildlife.
• Battle in the Rain: Normally (and ironically enough) this trope is Subverted; creatures could only be fighting in rainfall for a few seconds before the full force of the storm arrives and kills everyone outside. However, Downpour plays it straight by occasionally having the shelters fail, forcing the player to go out and potentially encounter predators during a non-lethal period of rain.
• Befriending the Enemy: Lizards can be tamed if fed enough squidcadas (2-3 does the job). Also, you can do very basic trade with Scavengers. They mainly deal using pearls, and can be traded with for items, safe passage through their tollbooths, or a free weapon depending on who you give it to.
• Benevolent Architecture: The Outskirts has plenty of poles in open spaces, to help beginners outmaneuver the game's first two predators: green lizards cannot climb poles, and you can leap over the more agile pink lizards once they climb after you.
• Big Fancy Castle:
  • Shaded Citadel is a huge, cathedral-like building shrouded in darkness.
  • The building traversed throughout Outer Expanse gives off a similar sense of adornment, albeit in similarly lavish wilds.
• Blackout Basement: The majority of the appropriately named Shaded Citadel is nearly pitch-black, forcing the player to find some source of light to move through any predators lurking in the dark there. Filtration System below the Subterranean is lit only by dim red lights while the slugcat has to contend with its labyrinthine layout.
• Book Ends: Both the opening scene◊ and the closing scene◊depict the Slugcat behind a huge-stumped tree.
• Boring, but Practical:
  • While there are plenty of items the slugcat can carry and utilize, none are as ubiquitous and handy as the humble rock. While these items do very little damage, they have a plethora of uses ranging from stunning creatures (specifically flipping Lizards' armored heads back for a clean spearing), as a noisy distraction for sound-sensitive creatures, to knock down hanging fruit or batflies, or even as a traversal tool as part of the game's advanced movement techniques. Whatever the use, you will always want/have one handy for majority of the game, even with slugcats who have other combat options, such as Artificer and Spearmaster.
  • The standard spear will be your staple weapon as it's almost as ubiquitous as the aforementioned rocks and equally as multi-purposed. Besides the obvious, it also serves to create platforms to climb on to help with traversal, with prudent usage even letting you bypass difficult sections. While the explosive and electric spears are more exciting, they're hard to come by and harder to part with, making the bog-standard spear your go-to for 95% of the game.
  • For the average player, you're much better off avoiding combat altogether instead of engaging it. As a slugcat, your killing potential is very small and the odds are always stacked against you, making it prudent to hide from or evade creatures unless you absolutely have to engage in combat. Of course, this only counts for slugcats who don't rely on kills for sustenance.
• Borrowed Biometric Bypass: One of Artificer's unique gimmicks is their (semi)permanently low karma, making passing through most karma gates impossible by normal means. To compensate, they can kill scavengers, who have their own karma levels exclusive to Arti's campaign, and drag their bodies to karma gates to "fool" them into opening.
• Call a Smeerp a "Rabbit": Almost nothing in Rain World is the animal it's named after, whether formally or colloquially.
  • It's easiest to start with the one exception: lizards. While they resemble salamanders more than lizards and have unusual capabilities, they are still lizard-shaped.
    • However, in a hilarious twist of irony, the actual named "Salamanders" are more akin to axolotls.
  • The "slugcats" comprising the player characters resemble rodents, and most frequently get compared to them, with Five Pebbles even outright calling Rivulet a "wet mouse". Word of God says they are neither furry nor slimy; they are naked.
  • "Vultures" are floating black boulders with seemingly ornamental, tentacle-like wings, and no other limbs. They move mainly by gaseous propulsion, and while their faces are relatively bird-like, they wear individualized masks, apparently made of carbon fiber. "King vultures" additionally have a pair of retractable, laser-sighted harpoons they launch to spear prey.
  • "Miros birds", named after the birds painted by Joan Miró (Fig 1◊, 2), look like completely wingless ratites (e.g. emus, maybe kiwis), but all black, without feathers, constantly snapping scissor-like metallic beaks, and glowing yellow eyes, which flash rainbow when the "birds" are blinded.
  • "Centipedes" are symmetric, having a head at each end. They kill prey by attaching both heads to it, and running a strong electric current through it. They can only see fully out of one head at a time, and they can only see motion.
  • "Spiders" never spin webs or have venomous fangs; they are solitary hunters, who capture prey by pouncing. Their backs have a number of tube-like growths coming off of them. "Spitter spiders" additionally spit leech-like sacs filled slow-acting paralytic venom, which drain into you if they hit you.
  • Red and sea leeches do not suck your blood like the majority of real-life ones; they simply attach to you in great numbers. Their weight pulls you to the bottom of the water, and you drown. Downpour's jungle leeches, however, do fact suck away your food pips.
  • "Kelp" is a single amphibious, omnivorous tentacle coated with what seems like dry, rustling vines. It captures prey by grabbing them with its tip and then drawing them into its den. They hunt entirely by sound.
  • Pole "plants" (also known as pole mimics) behave very similarly, with the difference being how they initially capture prey: they imitate poles, and any prey that tries to touch them will become stuck to them and will be drawn into their dens to get eaten.
  • "Daddy long legs" are based in design on epithelial cancer cells◊, being composed of fleshy, blob-like growths and extruding long, stringy tentacles to capture prey, which is drawn into the central mass to be slurped up.
  • Not even "fruits" are named honestly; they are apparently the pupae of an unknown bug. (They are also indestructible and invulnerable except by eating.)
  • Downpour gives us "gooieducks", which are odd, crunchy fruits, named after a kind of real-life clam.
• Cash Gate:
  • The player levels up every cycle they survive, and levels down every time they die (unless they eat a special flower). Passing between the game's regions requires you to be above a certain level. If the player has thoroughly explored an area but doesn't have the level required to move on (a likely occurrence given the game's crushing difficulty), they're forced to spend one or more cycles trekking already-explored territory leveling up. Food usually respawns after 2 or so cycles, so it becomes an exercise of memorizing where it spawns, then finding the best path to get it while avoiding enemies. Note that the game does not save between regions. If you pass through a gate to a new region and then die before finding a save point, you'll be stuck in the old region if this drops your level below the required number.
  • You must give a pearl to the Scavenger Toll to be granted passage, lest the Scavengers try to kill you.
• Central Theme:
  • Cycles of death and resurrection. The player character awakening back at the beginning of the day they dies is canon, they must prove their balance and worth to travel between regions, and the vanilla Slugcats' standard endings have them transcend the cycle.
  • The sheer impact of the passage of time. Each Slugcat's journey is on a different spot in the timeline, once the Ancients are gone. Shoreline wasn't the vast lake it was before the Hunter's time, and the Rot infestations slowly decrease and increase in Garbage Wastes and Five Pebbles, respectively; in the Saint's campaign, the Rot is gone from Garbage Wastes, and Five Pebbles winds up in a decrepit state.
  • The combination of spirituality and speculative futurism. The Ancients desired to ascend from their mortal coils, and they created huge supercomputers called Iterators to find a way to do so. The Iterators' actions and ultimate downfalls influence the ecosystems around them, and both they and intelligent animals seek out a Fantastic Nirvana.
• Colour-Coded for Your Convenience: Lizards, centipedes, and powerful spiders are color-coded by their different abilities.
• Combat Pragmatist: Slugcat is encouraged to use all aspects of their environment in order to survive, and every creature operates on this trope thanks to their Artificial Brilliance. For example, predators might leave Slugcat alone if it can hand them some food or can kill something in the vicinity for the creature to take. A vulture would rather prioritize the corpse of a lizard than go after the nimble slugcat, for instance. Since certain creatures get temporarily stunned if a spear can lodge itself in their torso, and things like invinciblity frames are near nonexistent in this game, it's also possible to stunlock enemies to death. Be weary that the same thing also applies to you as well however.
• Complete Immortality: Thanks to the cycle of life and death, nothing can die permanently, they will just keep reincarnating. The ancients tried using Void Fluid, but unless they rid themselves of desires, they were left behind as an Echo.
• Continuing is Painful: Dying lowers your karma by one level, which means you have go through another cycle just to get it back to where it was before.
• Crapsack World: Civilization has died out? Check. Quasi-permanent deadly weather? Check. Almost everything in the world is out to kill each other? Double Check.
• Critical Existence Failure: Averted. Damaged creatures struggle to move around, and often try to run back to their dens to recuperate. Injured lizards even drop their prey occasionally, allowing you to escape. A few creatures display Subsystem Damage of sorts; vultures lose the ability to fly, and a Daddy Long Legs' tentacles can be rendered useless. This can backfire horribly as a creature can still attack you even as they bleed to death, such as a dying scavenger managing to spear you before collapsing.
• Deadly Euphemism: The iterators refer to leaving the eternal cycle of life and death as "Crossing Out”.
• Distant Finale: The Saint’s campaign is the very last in Downpour's timeline, and the environment has drastically changed to evoke this. The monsoons are gone, being replaced by blizzards. Several of the creatures have changed appearances, the levels have different names, and Five Pebbles' structure is almost completely gone, among other things.
• Difficult, but Awesome: The slugcat has a ton of difficult-to-perform moves, like slides and backflips, that can be used to gain a tactical edge on his predators or otherwise assist with exploration. Mastering these moves can turn the initially slow and plodding slugcat into an absolute terror on the battlefield as you leap and duck around your opponents.
  • As for specific moves, the downward throw can be an exceptionally useful tool. Not only does it chuck a spear straight down, but it can pin enemies to the ground and either give you the chance to escape or follow up with successive spear throws. It can also be used in exploration to create miniature poles to stand on, giving you a little extra height to reach out-of-the-way paths and allowing you to jump over predators more easily. Reaching certain midgame shelters requires using this technique, so master it as soon as you can.
  • The Hunter demands this playstyle to be engaged with, as you have a stark 20 cycles to finish the game and primarily dine on large predators rather than plants, meaning you better be keenly aware of how slugcat can function in combat or die. Becoming a solid hunter means you get access to a bunch of excellent tools, like being able to store spears, consume predators for tons of food points, a pearl in his stomach, and a useful green neuron fly that can be instantly used to reboot Looks-To-The-Moon to full power. As a downside, his karma is incredibly low and due to being "karmically imbalanced" he cannot gain the maximum karma expansion from Five Pebbles and thus must search for Echoes if he wishes to ascend. Plus, it's freaking awesome to tear the predators hounding you to shreds with spears and rocks.
• Down the Drain: Drainage System, the underground parts of Shoreline, and Pipeyard's Sump Tunnel connecting to the latter are networks of tunnels with water filling much of them.
• Easter Egg: Moon's Submerged Superstructure is normally explored as part of the Rivulet's campaign. With clever use of jetfish and/or bubbleweed however, the region can be entered & explored as Hunter, Gourmand, Survivor, Monk and Saint, albeit at great risk and difficulty. The Hunter, Gourmand, Survivor or Monk can then find a torn white Cloak which can be given to Moon, the same one she wears during the Rivulet & Saint's campaign. Meanwhile, the Saint can find an extra Echo in the Bitter Aerie with unique dialogue noting how difficult reaching it is.
• Emergent Gameplay: A crowning example, and ingame this trope is almost enforced. The game tells you absolutely nothing about how its mechanics work outside of the controls, leading to the player discovering things on their own. This is taken up to eleven with the creature A.I, which is complicated enough to have a serious amount of variety and possible tactics depending on the creature.
• Eternal Engine: The majority of the world's regions take place in factories, but most of them don't function anymore. The exception is the built-to-last Five Pebbles subregion, although even that area is on the verge of shutting down.
• Extended Gameplay: With Downpour, several slugcats have endings that don't involve their ascension, and, given they're still alive and still more or less immortal, you can continue to play the game on that file either to reach the standard ascension ending or just to explore and survive for as long as you wish.
• Fake Difficulty: The slugcat has a large repertoire of moves at its disposal, but the player is only told about a handful of them and expected to learn the rest through experimentation. While some, like the backflip and the slide, might be learned during the course of natural play, more complex moves like downward spear chucking and slide flipping likely will not. What turns this into Fake Difficulty and not merely Guide Dang It! is that some of these advanced moves are important for traversing certain areas.
• Fantastic Nirvana: The Precursors became so advanced that they managed to find a way to achieve a state of nirvana free from the pains of reincarnation. In fact, they actually left behind a door to it so lesser beings like Slugcat can find it. It's not actually a door, but a secluded underwater area where great beasts/spirits swim around, and the only way to pass is to let one drag you down. However, unlike all the other predators in the game, it doesn't cause another death, and does indeed allow Slugcat's spirit into a paradise where they're reunited with their family. Similar endings happen with all the Slugcats but Saint, where after they take the ride, they briefly swim along with the many other Slugcat spirits before arriving at this paradise, with the only exception of the red Hunter slugcat, who can't keep up with the other spirits and sinks deeper into the abyss where a mysterious being seems to catch them.
• Fantasy Counterpart Culture: The Ancients (or at least, what we hear about them from Looks to the Moon) take a lot of cues from Buddhism, and other eastern religions. There is a focus on reincarnation, ridding oneself of earthly desires, and their garb draws from South Asian aesthetics.
• Fission Mailed: An unusual take on that trope. After most enemies incapacitate you and the Game Over appears, they'll start dragging your body back to their nest. Should the player just wait, there is a chance that another creature fights with your killer over your body, and that you end up getting dropped from their mouth. Should that happen, the Game Over disappears and you re-take control of your character, allowing you to continue playing as if you were never killed. If the enemy's attack kills the slugcat instead of incapacitating it, its eyes will be crossed out instead of shut.
• Going Cosmic: From the beginning, the game is about survival, and hopefully finding your family. Then you meet nigh-omniscient AIs, echoes of Precursors, and find yourself on the path to achieve transcendence. Near the end of the game, a cosmic worm leads you to the souls of your kin. Any questions?
• Guide Dang It!: The game takes less than 5 minutes to stop holding the player's hand. After that, the almost complete lack of text, clear feedback, or explanations of any sort means that players will discover most game mechanics by looking it up online, from other players, or through experimentation. The game does give solid enough directions to complete it by following the Observer's directions and exploring, but it's still very easy to get lost or blunder into a region you're not prepared to take on.
• Hailfire Peaks: Several regions consist of different environments placed next to each other, without those being distinct subregions:
  • Pipeyard is designed as a varied "crossroads" between multiple regions near the west side of the game world. The upper side has drier flats and holes, but its lower levels have dimly lit ponds, as well as the tighter corridors of Filtration System creeping from said subregion.
  • Shoreline has large, deep lakes with only a few spires jutting up from them. However, below them lies a clean sewer system with almost nothing deadlier than some Jetfish.
  • Shaded Citadel's highest floors are decently lit with big arches supporting them. However, its middle levels are normally pitch-black, and the path to the Memory Crypts is a quiet grotto, with stagnant water inhabited by Monster Kelp and illuminated by Lilypucks.
  • Chimney Canopy's bottom, entered from Industrial Complex, is composed of flats and large tubes that are hospitable enough for the landbound Pink Lizards there. However, its heights are more dangerous to traverse, necessitating travel on more vertical and horizontal poles, and smaller platforms easily blocked by Vultures.
  • Outer Expanse's main area is a tangerine, tropical wilderness, but such constantly permeates a bright, fancily-carved villa.
• Jungle Japes: A couple of areas are very jungle-like (sharing the unusual "blinking flowers" as background plants):
  • The Outer Expanse is filled with tangled forest life, along with a damp climate and some patches of Worm Grass laying around.
  • In Saint's campaign, Drainage System has been overcome with underground plant life, making it a more lush ecosystem inhabited by spiders and centipedes.
• Kaizo Trap: The Depths is almost entirely devoid of enemies or hazards, with the Guardians only attacking if you arrive without maximum karma. However, there's a drop that is large enough for a careless player to die by fall damage, just a few screens away from finishing the game.
• Karma Meter: Scavengers, squidcadas, lizards, jetfish, and rain deer have reputation systems where their behavior changes based on how the Slugcat treats them. Protecting and feeding creatures, and giving items to Scavengers, increases reputation. Attacking creatures, stealing from Scavengers, and trespassing their tolls without high reputation will lower reputation.
  • Ironically, the karma system does not count and is instead a sort of lives system (at least in Expedition Mode)
• Law of Chromatic Superiority: The strongest, deadliest variants of Lizards and Centipedes are red.
• Level in the Clouds:
  • Chimney Canopy and Sky Islands are primarily made of small structures extremely high above ground, making bright skies above an unsurvivable drop a constant.
  • The Exterior's Wall, Metropolis, and the Luna of Spearmaster's Looks to the Moon feature this geometry to a lesser degree, but they are also high enough to play this trope literally (too high for rain to be a threat).
• The Many Deaths of You: Eaten by bigger animals, eaten by carnivorous plants, drowned by leeches, electrocuted, mauled by the rain, fell into a bottomless pit, and every variation of the above...
• Multiple Endings:
  • Every slugcat can ascend by finding Five Pebbles and/or enough Echoes to attain a maximum karma of 10, then going to the Void through the bottom of the Subterranean's Filtration System. This is the standard ending for all three vanilla Slugcats.
  • If you die as the Hunter with cycles counting below 1, your playthrough is terminated, your final score is tallied, and the Hunter permanently dies, having turned into a Rot cyst.
  • The Gourmand's standard ending is to unlock the Subterranean-Outer Expanse gate by consulting Five Pebbles, and then relay its findings to the slugcats at the end of the region. If the Gourmand's food tracker is complete, the ending cutscene will be expanded, and the Hunter, Gourmand, and Survivor will be able to find and care for Slugpups.
  • Completing the Gourmand's campaign unlocks the Outer Expanse gate for the Monk and Survivor. If the latter two return to their home, the Survivor will find it without the respective family they sought, but the Monk will reunite with the Survivor and their new Slugpups.
  • The Artificer's standard ending is to enter Metropolis and kill the Scavenger chieftain. This finalizes her revenge, reduces her standard max karma to 1, and causes the surviving Scavengers to flee to the Garbage Wastes.
  • If the Artificer attempts to ascend through the Depths, the Void Worm refuses to drag her to the afterlife. She swims downward anyway and reunites with her dead pups for just a few seconds, before her soul ceases to exist.
  • The Rivulet's standard ending is to bring a Rarefaction Cell from Five Pebbles' Rot to Moon, rebooting some of her systems and letting her consult Five Pebbles one last time.
  • The Spearmaster's standard ending is to deliver Moon's overwritten pearl to the top of the Communications Array, allowing her to send her last message before most of her structure collapses.
  • The Saint's campaign downplays this into multiple variants of one ending. Once they reach Five Pebbles, their new powers allow them to ascend Pebbles and/or Moon. Once they traverse Rubicon in place of the Depths, they meet up with whichever Iterators they ascended, and then rise back from the Void, in order to become an Echo that helps other creatures ascend.
  • ??? going through all the trouble to ascend takes them to a dating simulator where they try to mate with any of the other five Downpour slugcats. It is very much Played for Laughs, and has multiple endings in and of itself.
• Never Trust a Trailer: The Gourmand's section of the Downpour Slugcat Showcase shows it looking between a Blue Fruit and a Spear, as if planning to craft them together. In the gameplay proper, the Gourmand cannot use Spears to craft.
• One-Hit Kill: There are two things that can kill virtually anything in the game:
  • The first is the Singularity Bomb, which when thrown will create a distortion radius that will one-shot anything within, including Guardians, Leviathans, and Rot creatures. It won't work on Five Pebbles, though, as he will fling both the Slugcat and the bomb out in a panic.
  • After gaining maximum Karma, the Saint can slowly ascend any creature, including Leviathans and Five Pebbles^note who is in a very decrepit state in a Saint playthrough compared to others. The only enemies that can survive a single use are Guardians, which take three for it to work, and the Void Worm, which leaves after one use.
• Organic Technology: Before they vanished, the Ancients made extensive use of "purposed organisms", creatures they designed to fulfill particular tasks, such as cleaning the insides of pipes. Looks to the Moon and Five Pebbles are two such organisms, built to be supercomputers, but don't be deceived by the humanoid "puppets" you interact with — their bodies are made up mostly of "microbe strata" that extend across their whole facilities (or used to, in Looks to the Moon's case). Looks to the Moon theorizes the Slugcats themselves are evolved/descended from purposed organisms, and it's likely most of the other creatures you encounter have similarly unnatural origins.
• Painting the Medium:
  • The rain is depicted as shears in the pixel art and screen shake, as if it's literally tearing the world apart.
  • As you approach the Void Sea, the pixel art begins to warp and distort, the outline of your character becoming more and more abstract. This is used to show just how alien the whole place is.
• Palmtree Panic: Much of Shoreline consists of small "seasides" of land next to a lake teeming with its own adapted life, resulting from the spillage of water from the collapse of Looks to the Moon next to Waterfront Facility.
• Permadeath: The Hunter can suffer this if you don't finish the game within 20 cycles. Upon reaching 0 cycles, the Hunter begins to have seizure-like spasms and moves at a reduced speed. Any deaths while under 0 cycles will result in the run being over.
• Perpetual Storm: Every day, a drought of up to 20 minutes occurs, during which the phases of gameplay take place. The player can keep track of how long until the storm restarts by checking the rain clock on the map screen. As the rain starts hitting the ground, the screen starts shaking and the lights grow dim. The water level rises by many screens, and in places exposed to the sky, the downpour will stun any player who tries to move through it. Should the player fail to reach a safe house before the main of the storm arrives, which takes about a minute, the player instantly dies, no matter where he is. It can be assumed that even if the player manages to find a place safe from the rain/water, the drop in temperature caused by the nearby flowing water will cause death by hypothermia.
• Planet Heck: Rubicon, internally initialized after "Hell Region", is Saint's counterpart of the Depths. It's an underworld region amalgamated from familiar geometry and full of powerful creatures and lethal, lava-like Void Fluid.
• Polluted Wasteland: The Garbage Wastes, with their sickly green water and buzzing flies fit this trope perfectly.
• Primal Fear: The game practically runs on this. To start, nearly every enemy is out to eat you, most likely alive, and many of them are essentially monstrous versions of known unpleasant animals such as bugs, spiders, squids, reptiles, leeches or vultures. There are multiple dark and claustrophobic areas. And you have to constantly scavenge for food lest you starve.
• Shout-Out: One of the generic pearls you can give to Five Pebbles would be about a simulation called The World Machine, which sounds awfully famillar to anyone who has played One Shot.
• Silliness Switch:
  • Playing as ??? makes an otherwise dark, atmospheric game completely silly and somehow even more ludicrously difficult, and ends with a dating sim that is played entirely for laughs.
  • Downpour DLC adds the Eggspedition secret (warning: linked video may contain spoilers), which requires you to bring each one of the 8 main playable slugcats over to specific points in the world to wait a few seconds. This unlocks an optional rainbow skin that makes your playable character light up dark areas with a rainbow of colours.
• Spiritual Antithesis: The Downpour DLC, while providing additional survival gameplay, is one to the base game. The narrative at Rain World's launch evokes fear of a dying world: to live is to suffer, and the Survivor's only way of reuniting with its family is to transcend the mortal plane. The More Slugcats campaigns, however, show what it means to love a dying world. Ascension becomes an underwhelming alternative, the Saint's only ending is to become an Echo out of the selfless desire to put the world to rest, and the Gourmand's philosophy steers the farthest from the Survivor's: the former supports its mortal colony and is called an indulger of the simple things in life.
• Story Breadcrumbs: Provided in the form of pearls, given to Looks to the Moon, dialogue after reaching an echo, and through the way the ecology has adapted to various locations.
• Tide Level: Downpour has versions of Drainage System and Shoreline's path to Subterranean where drainage machninery is still active enough to make the water levels repeatedly rise and fall. This was implemented to allow traversal by the Artificer, an explosion-attuned Slugcat whose lungs detonate if she stays underwater for more than five seconds.
• Timed Mission:
  • Almost every region is under threat by a storm at the end of each cycle. If the player doesn't make it to shelter in time, they will almost certainly die through either the flooding of interior areas or the sheer force of the rain outside. This is most prominent when playing as the Rivulet, as its cycles are significantly shorter than usual.
  • The Hunter has a terminal illness plaguing it. It starts the game with 19 cycles of being healthy and can have 5 more tacked on if you know where to look, but once those are up it begins to suffer seizures and penalties to its statistics, and if you're killed after the counter hits zero, your save file is rendered unplayable.
• Trial-and-Error Gameplay: Though less about figuring out the exact sequence of moves to make in any situation, like many examples, and more with figuring out the mechanics themselves, which are often obtuse. "Why did those masked monkeys kill me?" "Is this species of red-tinged plant going to eat me, be explosive, or give me a rich source of food?" "I hit that lizard in the head, why didn't it get hurt?" Well, the only way to find out is to try again. Or look it up on the wiki.
• Underground Level: Subterranean consists of dimly-lit caves, and the bottoms of Pipeyard and Shaded Citadel are water-filled lakes within the ground. These areas comprise the bowels of the game world.
• Unlockable Difficulty Levels: The Hunter, as well as Downpour's five slugcats, are unlocked by beating the game as previous slugcats.
• Urban Ruins: Metropolis is an abandoned city above Five Pebbles' can, its systems running autonomously even as it is being ransacked by Scavengers.
• The Very Definitely Final Dungeon: Rubicon, only accessible in Saint's campaign, takes what was once more or less just a brief victory lap to the ending and turns it into a sprawling, hellish Marathon Level comprised of nearly every other biome in the game .
• Video Game Cruelty Punishment: Eating one of Looks to the Moon's neurons will anger her Overseers, who will then cease guiding you. Curiously, if you work to bring some neuron flies back to her, Moon will eventually forgive you. She outright states once you have the Mark of Communication that it's hard to blame you because, to her, you're a speechless animal who doesn't know right from wrong.
• Warp Whistle: Surprisingly, you can use a Passage to warp to a previous shelter after hibernating. Less surprisingly, it's enabled by a limited-use item unlocked by completing achievements.
• Who Wants to Live Forever?: The central conflict of the setting. All of the ancients are gone, leaving behind massive supercomputers called iterators, all trying to find a way to end their immortality without using the Void Fluid. One of them, Sliver of Straw, found it, but for whatever reason, was unable to tell the rest. This sets the events of the game in motion.