: This indicates that the full download has been split into multiple parts, and this is the third volume in that set. You would typically need all parts (e.g., part1, part2, part3) in the same folder to successfully extract the contents.
The text you provided, , appears to be a specific archive filename typically associated with a segmented download of a video game. Single.Player.Horror-DARKSiDERS.part3.rar
: This describes the genre of the game included in the file. : This indicates that the full download has
: This is the name of a well-known "scene" group that releases cracked versions of games. Single.Player.Horror-DARKSiDERS.part3.rar