While this file format is common in file-sharing communities, please be aware of the following:
The filename you provided, Rainbow.Dreams-DARKSiDERS.rar , indicates a "scene release" by the group , a well-known warez group that typically releases cracked versions of PC games. Game Overview Developer: Neko Game Genre: Indie, Casual, Adventure Platform: PC (Windows) Release Date: August 2021 Safety & Legality Rainbow.Dreams-DARKSiDERS.rar
You can typically find the official version of this game on platforms like Steam if you wish to support the developers directly. While this file format is common in file-sharing
Archive files from "scene" groups can sometimes contain malware or PUPs (Potentially Unwanted Programs). It is highly recommended to scan any such file with up-to-date antivirus software like Malwarebytes before opening. Rainbow.Dreams-DARKSiDERS.rar