Rain World will get a new expansion called Rain World: The Watcher on March 28, 2025. The release will co me with a new slugcat to play as—the Watcher, AKA the Nightcat—and will be set in a wholly new-looking area of the Rain World with its own strange ecology that we get glimpses of in the released trailer.
That includes some drifting fluffy piles of what may well be snow, which is a big twist for a world with such intense downpours that they literally kill you if your poor little Slugcat if they don't have somewhere to hide. Though perhaps Nightcat doesn't care so much: It stands in a slight drizzle seemingly unconcerned in the trailer.
"The wilds that await will be unlike all that's come before," says the expansion's brief description. "Unknown creatures stalk and climb and dive and hunt. New breeds rip and pluck and burrow and hide. Predator and prey redefined. And through the middle of it all, a lonely lost slugcat trying their best to outlast the ravages of a warped world."
Rain World is a cult hit survival-exploration-metroidvania with one of the most intriguing landscapes in videogames. Its creatures follow their own rules, exist outside of your own character, and hunt to survive. They especially hunt your Slugcat, the adorable and clever little creature you play as.
"It’s a platformer and a survival game, but neither of those categories are a neat fit for Rain World’s peculiar brand of misery. There are traces of other games’ DNA, such as the original Dark Souls’ bonfire system and the roaming, improvisational foes of Alien: Isolation, but Rain World stands apart as one of the most alienating and difficult games in recent memory, previously mentioned company included," said PC Gamer reviewer Shaun Prescott back in 2017.
Rain world has, since, gained difficulty settings. They work quite well. There was also a giant expansion called Rain World: Downpour back in 2023. You can find Rain World and Rain World: The Watcher on Steam.