This is a standard compressed archive format used to distribute these large updates across file-sharing mirrors like MegaUp or torrent trackers. Far Cry New Dawn eventually received a 60 FPS update
Players can now download the update from various sources, including torrent sites, as a CODEX.rar file. This update is compatible with the PC version of the game. Far.Cry.New.Dawn.Update.v1.0.5-CODEX.rar