Rain World is a 2017 survival-platform video game developed by independent studio Videocult and published by Adult Swim Games and Akupara Games. It was released for PlayStation 4 and Windows in March 2017 and Nintendo Switch in December 2018. The player guides a "slugcat", an agile animal resembling a cat-slug hybrid, as it fights for survival in a derelict and hostile environment. The slugcat traverses the remnants of an industrialized ancient civilization in search of its lost family. It uses debris as weapons to ward off lethal predators, scavenges for food, and attempts to reach safe hibernation rooms before deadly torrential rain arrives. Rain World can be played alone or with multiple players; there is also a sandbox mode.
Development began in 2011 and included a successful Kickstarter campaign in 2014. The two-man team intended to simulate a unique, realistic ecosystem, in which creatures act independently from the player and perpetually roam the environment. Rain World uses real-time procedural animation and conveys much of its narrative through environmental storytelling, adopting an adaptive low-fi and electronic soundtrack. The player is given little explicit guidance so that they would feel like a rat that lives on subway tracks, learning to survive in an environment without comprehending its higher-level function.
Rain World received mixed reviews from critics, who praised its art design and fluid animation, but criticized its difficulty, checkpoint system, and controls; some of these concerns were addressed with later updates. The game was nominated for awardsincluding an honorable mention for the Seumas McNally Grand Prizeand garnered a cult following and a large modding community. A downloadable content pack titled Downpour, adapted from a popular community mod, was released for Windows in January 2023 and ported to consoles in July 2023. It added five slugcat characters with unique abilities and was positively received by critics. A second content pack, The Watcher, was released for Windows in March 2025 and ported to consoles in September.
Gameplay
Rain World is a two-dimensional (2D) survival-platform video game that takes place in a post-apocalyptic, industrial environment. The game follows the player-controlled "slugcat", an animal akin to a cat and a slug. The slugcat freely explores screens shown individually by squeezing through pipes or walking; some screens spawn creatures that wander the region, which the slugcat may defend against with spears and debris. It must jump, swim, and climb poles to avoid enemies while foraging for food which must be consumed to hibernate in scarce, designated safe rooms. Hibernation spots serve as checkpoints where it returns to after death; if the slugcat does not reach a shelter before the end of the cycle, rain will kill it in an ensuing flood.
Upon death, the slugcat loses one "karma" level, which is gained upon hibernating. The slugcat can prevent losing karma by eating a yellow "karma flower". The flower appears in set locations and is replanted wherever the slugcat dies after eating it. It must meet a specific karma level to pass through gates set at the borders of the game's 12 regions. Rain World offers little to guide the player apart from holograms by a worm-like creature that monitors the slugcat. The holograms point towards food and story-related events, though this assistance becomes rarer over time. The player may view an in-game map to review their exploration progress.
Predators range from camouflaged carnivorous plants to large gas-producing vultures and colored Komodo dragon-like lizards; some creatures are friendly but easily provoked, like the "scavengers", which are agile like the slugcat and equipped with explosive spears. Many enemies can kill the slugcat in one attack. Some have variations that possess unique characteristics. All creatures possess dynamic behavior and perpetually wander independently from the slugcat, occasionally battling and hunting each other; without a set path for predators to traverse, the slugcat's exploration is unpredictably hindered. The slugcat may carry two items with its hands. It uses its right hand first when throwing and may swap the items' places. Some foods grant status effects when consumed, like slowing down time.
Along with the default slugcat, the player may choose to play as the Monk and Hunter slugcats. As the Monk, creatures are less aggressive and the slugcat needs less food to hibernate. The Hunter, a carnivore with a bigger appetite, must fight and feed on larger creatures while also being capable of carrying extra spears. Other game modes include a multiplayer arena mode, where up to four players battle each other, and a sandbox mode, where the player freely spawns and interacts with objects and creatures.
Downloadable content
Rain World has two downloadable content packs (DLCs), the first being Downpour. Downpour triples the game's world size and adds five slugcats and ten regions, accessed separately from the original game's content. Each slugcat features a different set of abilities. The Artificer can jump twice midair and create explosives. The Spearmaster produces an infinite amount of spears, but piercing other creatures is the only way it receives food. The Rivulet, a semiaquatic slugcat, has increased agility, but must deal with more frequent rain. The Gourmand uses its weight to damage and stun enemies and can craft usable gear by merging items, though it requires a tremendous amount of food to stay alive. The Saint has a tongue that can grapple onto objects, granting it high mobility, but cannot throw spears and is prone to freezing to death.
Downpour also adds three game modes: Safari mode allows the player to spectate the ecosystem and control any living creature. Challenge mode provides 70 scored challenges with preset objectives. Expedition provides random missions that award experience points upon completion, which the player uses to purchase upgrades and activate difficulty modifiers. Downpour release was accompanied by full local cooperative multiplayer functionality and modding support so that players could add user-generated content.
The second DLC is The Watcher, which adds regions, creatures, and the Watcher slugcat.
Plot The narrative is conveyed through the environment, dreams during hibernation, and the worm-creature's holograms. The game begins when a family of slugcats is struck by the rain. They are separated from two of their childrenincluding the player's slugcat, which is flushed into the long-abandoned remnants of an industrialized ancient civilization.
Eventually, the slugcat stumbles upon Five Pebbles, a massive, infected, superintelligent, and semi-biotic artificial intelligence called an "iterator". After climbing above the clouds and traversing through his megastructure, the slugcat meets his avatar. Pebbles explains that, like all living things, the slugcat is trapped in a cycle of death and rebirth. The ancient species who built him and the surrounding structures have disappeared, and they constructed the iterators as beings tasked to find a way to end the cycle. He infers that the slugcat seeks its end, and directs it to where it can free itself. Following his guidance, the slugcat travels underground and enters the ethereal "Void Sea", a body of "Void Fluid", where it can "ascend".
More information about the setting is obtained by bringing pearls to a damaged iterator named Looks to the Moon, whose structure collapsed and partially submerged into the shoreline. The pearls document various religious, cultural, and historical details about the ancient civilization and the aftermath of their disappearance.
The Hunter's story acts as a prequel; it begins with a pearl, a green "neuron fly", and a 20-cycle limit before the Hunter can permanently die of sickness. The slugcat travels to find a comatose Looks to the Moon and revives her with the neuron fly. When read by Moon, the pearl reveals the Hunter was sent by an iterator named No Significant Harassment.
Downpour Downpour individual narratives, though presented nonlinearly in-game, are shown below chronologically.
In a plan to self-destruct, Five Pebbles overexploits his water source shared with Looks to the Moon; Moon interrupts Pebbles, botching the experiment and infecting his structure, leading to him cutting communications with the local iterator group. The iterator Seven Red Suns sends the Spearmaster to deliver Pebbles a pearl ordering him to end his overuse of water. The message is refused and the slugcat is expelled. Given the pearl, Moon overwrites it and orders the Spearmaster to bring it to a communications array. Moon's message announces her imminent collapse. The Artificer witnesses the death of its children to primate-like scavengers. Stumbling upon Five Pebbles, Pebbles sees use in the slugcat, sending it to exterminate the scavenger population that has overrun the city atop his structure. The Artificer massacres the scavengers and defeats their chieftain. The Gourmand's story takes place after the Hunter's. Stumbling upon Five Pebbles, Pebbles infers the slugcat wishes not to ascend. He unlocks the gate to a slugcat colony and asks the Gourmand to prevent further slugcats from meeting him. The Rivulet's story takes place after the original game's story. The Rivulet, a semiaquatic slugcat, must survive through short rain cycles. Eventually, the slugcat enters Five Pebbles' infected, barely functioning complex, and takes the "rarefaction cell" which provides power. Without the cell, Pebbles accepts his eventual death, and requests it be given to Moon. By traversing her submerged superstructure, the slugcat activates the cell, restoring Moon's functions. She initiates a broadcast to the iterator group, signaling her revival. Far into the future after Pebbles collapsed and the rain has given way to fluctuating blizzards, the Saint emerges from the Void Sea and awakens on the surface. The slugcat explores to visit "Echoes", spirits from the ancient civilization who entered the Void Sea but failed to ascend. Eventually, the Saint gains the ability to ascend creatures. It attempts to enter the Void Sea but is transported to the hell-like "Rubicon". The slugcat roams and finds the Void Sea; wings sprout from the Saint resembling an Echo's and it awakens on the surface again.
Development Rain World was developed by Videocult, an indie group made up of Joar Jakobsson and James Therrien (also known as James Primate). Jakobsson served as the artist, designer, and programmer, while Primate wrote the soundtrack, handled the studio's business, and designed levels; this became Primate's first experience developing gameplay. Before creating Rain World, Jakobsson was a graphic designer in Sweden and novice video game developer who taught himself to animate sprites. He had little industry experience when development began in 2011.
A friend encouraged Jakobsson to pursue the concept of procedural animation, a method that generates real-time, unique animations. He then designed an animal and posted development updates on his YouTube channel, with one commenter dubbing the creature a "slugcat". Jakobsson was interested in abandoned environments and what they reveal about the people who occupied them. Inspired by feelings of foreignness while living as an exchange student in Seoul, South Korea, a core idea was to recreate the life of "the rat in Manhattan". This rat understands how to find food, hide, and survive in a subway, but does not comprehend the subway's structural purpose or why it was built. In 2012, Primate found Rain World on an Internet forum for indie games. Intrigued by the art style, he successfully pitched 12 tracks to Jakobsson after experiencing a nightmare where the game "was filled with garbage music".