Or compare it with the Just Cause 2 multiplayer mod, which requires you to own the game on Steam, and acts like a DLC. http://store.steampowered.com/app/259080

Or compare it with the Just Cause 2 multiplayer mod, which requires you to own the game on Steam, and acts like a DLC. http://store.steampowered.com/app/259080/ http://store.steampowered.com/app/259080/ Edit: Before they got on Steam, they required you to log in on their site and the mod with Steam's OpenID system, which they could use to check if you owned the game or not.