Rain World

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.

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 children—including 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.

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".

The game received mixed reviews upon release, according to review aggregator website Metacritic, with 43% of critics recommending it according to OpenCritic. Video game journalists praised the game's art design, but characterized its gameplay as harsh, calling its deaths unavoidable, controls sloppy, and hibernation requirements time-consuming.

However, Rain World's active fanbase earned the game cult status and a large modding community. Downpour was received positively by critics, and—as a DLC made of community-created content—significantly contributed to Rain World's status as a cult hit according to journalist Simon Carless; Downpour sold 182,000 units on the video game distribution service Steam in the months surrounding its release and 280,000 units from March 2022 to February 2023.