The first and easiest method is only available when you buy the game on Steam. There are two ways to install mods in Cities: Skylines. When combined with the official DLCs, the customization options become essentially limitless. With the right mods, Cities: Skylines can drastically change the rules vanilla players are used to and allow you the further realize the vision you have for your city. RELATED: Cities: Skylines: The Best DLCs You Can Get Today While the base game has a lot to offer, experienced players might want to elevate the level of detail in their cities or even add more content. Cities: Skylines is an incredibly detailed city-building simulator with an incredible modding community.