I haven't checked in on any of my Cities: Skylines creations lately, but last time I looked they were suffering from a number of problems, like traffic, lack of educated workers, a slight overabundance of blimps, and the fact that some idiot built a creamatorium and a garbage dump right next to a playground. Pollution, of course, is an ongoing issue in any Skylines city, but some solutions are on the way.
The next Cities: Skylines expansion will address pollution problems by letting you go green. Green Cities "adds 350 new assets to the core game, adding a massive selection of new visual options, complete with eco-friendly buildings, organic shops, electric vehicles, and new services designed to make pollution a quaint notion of the past."
We don't have a release date—the expansion only promises to arrive on the wind "later this year." We don't have a price yet either, but even if you decide not to buy it there will be the usual smattering of freebies, in this case "electric cars, road modding, changes to noise pollution, and more beautification options in the form of parks and trees, among other things." Find out more here.