The .rar format is used to reduce file size and provide error-checking (SFV) to ensure the data wasn't corrupted during download.
DARKSiDERS (a known "Scene" group specialized in cracking and releasing PC games). Game Title: Let's Sing 2019 Format: RAR Archive (Part 2 of a multi-part split volume). Context and Content Lets.Sing.2019-DARKSiDERS.part2.rar
This specific file cannot be opened or used in isolation. To extract the game, a user must have all accompanying parts (e.g., part1.rar , part3.rar ) in the same folder. Lets.Sing.2019-DARKSiDERS.part2.rar
These files typically circulate on BitTorrent sites and "warez" forums. Technical Analysis Lets.Sing.2019-DARKSiDERS.part2.rar