Cities: Skylines, as you can probably guess from the name alone, is a semi-serious city building and management sim. It unfortunately doesn't offer much in terms of challenge for 'tryhards' like myself, but if your only wish is to design the most perfect city in all of existence then Cities: Skylines is almost unmatched.
And after two incredibly successful years the developers have decided to bring a splash of color into Cities: Skylines with a free bit of DLC. The upcoming mini-expansion titled "Pearls from the East" will bring with it three buildings to mess around with: a Panda Zoo, a Chinese Temple, and the Shangai Pearl Tower. Why exactly are all of the buildings connected to China, that I don't know, but I do like the idea of filling my city with a whole bunch of pandas!
For those among you looking for something a bit more concrete, you might want to take a look at the upcoming Mass Transit DLC. This one will be a paid piece of DLC, but it will bring with it new scenarios and landmarks, roads and bridges, as well as a whole bunch of new vehicles such as: blimps, ferries, cable cars, and so forth. If you're interested in learning more here's the recently posted announcement trailer: