File: Cos_ro2_dlc.rar ... -

Knowing the internal file extensions (like .pkg, .txt, or .data) would help me give you more exact steps.

: Drag the extracted files into the main game folder. If prompted to "Overwrite existing files," select Yes (this is usually required for mods/DLC to work). File: COS_RO2_DLC.rar ...

Since .rar is a compressed archive, you will need software to open it. : Use 7-Zip (free and open source) or WinRAR . Knowing the internal file extensions (like

: Find where your game is installed (e.g., C:\Games\RO2\ ). File: COS_RO2_DLC.rar ...