As of April 7th of 2025, Rain World’s The Watcher has been out for a couple of weeks, and so far multiple of the endings have been discovered. With the campaign comes a new slugcat named the Watcher, a bunch of canonized regions that originally were custom regions, and many new creatures.

Rain World: The Watcher plays much differently to the base game and Rain World Downpour, however, requiring echoes and wormholes all around the world to traverse. The Watcher campaign focuses more on stealth than killing, and starting in a new subregion called Hydroponics that is attached to Industrial Complex, it can be extremely confusing.

With all currently found lore, either the Watcher can see in the eyes of a young Ancient, playing with toys and messing around with them after being dragged by a rot-infested Void Worm. They also, however, can spread the Rot from region to region using their ability to warp into different regions which takes away the effect karma flowers supply them. Once every region has become rot infested, they will witness an iterator-like being that was the one slowly killing the world, resulting in millions of karma flowers forming. 

In total, the Rain World’s Watcher campaign has added a lot of new mechanics and features that will get updated and fixed in time. There has been complaints such as how odd and slow the progression feels, how the AI for the new creatures is buggy, and how large some sub-regions are. Overall though, Rain World’s Watcher campaign is highly acclaimed and recommended, being only $13.99 USD in the Steam Workshop. Unfortunately though, as of right now it is only on the computer version of Rain World through Steam.