"P2P" groups don't have the same reputation standards as established "Scene" groups (like Razor1911 or SKIDROW). The .exe could easily contain a trojan or a crypto-miner.

Since this is a P2P release, you should be extremely cautious. These files are common vectors for:

A punishingly difficult survival platformer where you play as a "slugcat."

Version 1.9 was the major update that accompanied the Downpour expansion, adding new slugcats (The Gourmand, The Artificer, etc.), hundreds of new rooms, and the Safari mode.

Rain World is a masterpiece developed by a small indie team (Videocult). Because the game relies heavily on its (found on RainDB or the Steam Workshop), the official version provides a significantly better experience.