After Dark is the first expansion to Cities:Skylines. While it introduces the much awaited Day and Night cycle, it also brings with it new city planning options and buildings. I really like how the game transitions to night. It's a very gradual process, with the first traffic lights coming on just as the sun goes down, then a few moments later the building lights come on. It's a simple thing but really adds to the atmosphere. One thing I found interesting is that there is an option to toggle off the night. This essentially allows you to use the new buildings and features without the game going to night.
First off you will notice there are special tourism and leisure buildings. Some are found under the decoration menu under the new tab tourism/leisure, while a couple are under the unique buildings tab. To be able to place the ones under the Unique buildings tab you must first meet the requirements. The Casino for example requires you have 5000 squares of leisure buildings built while the driving range requires the 5000 tourism buildings.
This is perhaps one of my favorite features of the expansion. To get the buildings required for the above example, you can now specialize your commerce like you could industry in the base game. If you place a commercial area in a district then set that district's specialization to tourism you will start seeing lots of hotels pop up. If you instead set it to leisure, you will see nightclubs and other late night venues take over. These options really help diversify the look of a city.
There are new city service and transport buildings as well. Prisons gives you a place to house criminals but people wont be happy living right next to one. The new bus station gives citizens a place to change bus lines. The international airport is huge. It needs a big flat area to be placed in, but it comes with a built in metro station so the trade off is worth it. The cargo hub was one of my favorite new buildings. It combines the cargo port with a cargo train station. A couple of new road options become avaliable as well. If you like using buses but they sometimes get in or cause traffic jams, you can try upgrading the problem areas to have dedicated bus lanes. If you'd rather give your citizens an alteritive to walking there is also bicycle lanes. Last and probally my fave of the new transport options is the taxi depo and stands. These don't require you to set up a line like other modes of travel. Instead you place a depot, place some stands and taxis will find fare when needed. It's great to have these anywhere you expect tourists such as by the airport.
At night, more than just the lights come on. Crime rates increase. While less noticeable in more bustling cities, traffic tends to slow down, making it a good time to do roadwork. Of course, leisure commercial buildings stay open all night unless you opt for the policy to have them close at night. Which you may want to do for the ones near residential areas. Once I had leisure commercial areas, my residents complained about noise. That is something I don't remember them complaining about in the base game, as it was easy to keep them away from major sources of noise pollution. Also it is worth noting that the solar plant wont produce energy after the sun has gone down. There are is also a new policy to encourage people to use dedicated bike lanes.
As mentioned before there are a few new playable buildings in the parks area. These are things like a beach volleyball court, fishing pier, or a pier restaurant. These are handy for residential areas along the shore, which you will want to be having now because another big change is that land value is now higher for shoreline properties. Right before I managed to get a screen cap for it, apparently someone had died in my skate park. I had seen two people carrying something and it was only as the hearse drove away I realized what was going on. The little details are really nice on the new buildings as such as seeing people fishing off the aforementioned pier.
Allin all I really enjoy After Dark. Its a simple expansion but brings with it several fun features and buildings, making an already great game even better.