A Master Class in City Building

I’ve always enjoyed city builder games. There’s something monumentally satisfying about watching a city grow from a few small buildings to a sprawling metropolis. Unfortunately, I hadn’t found a good city builder for a very long time – not since Simcity 4, which I played obsessively when it came out. And then, a few years ago along came Cities: Skylines. It was the true spiritual successor that the modern Simcity had thoroughly failed to be. And looking at it more closely, I have begun to appreciate even more what makes the game great.

Teaching

In my previous post, I praised Game Dev Tycoon for not explicitly teaching anything, but rather letting the player learn. Cities is significantly more complex than Game Dev Tycoon, and so it gives us an opportunity to look at how explicit teaching can be handled well.

The first kind of teaching you’re given is something seen in many games: tips on loading screens. While these may seem artless, they’re actually quite clever. They take a moment of forced downtime, and use it for the player’s benefit. It’s a simple technique, but effective.

Once the game starts properly, you’re given an explicit task – to build a road and zone the land alongside that road. There are a number of icons along the bottom of the screen representing your toolbar, but cleverly most of these are blacked out – you only have access to the few you can actually use at this point in the game.

Further, every icon has information when you click on it: the zoning tool clearly shows which zones are residential, commercial and industrial; the road tool marks exactly what kind of road you will be laying down. By keeping the number of options small at the start, the game encourages experimentation, while still giving you nudges in the right direction.

These nudges are well executed – they keep you on track without holding your hand. For example, as more and more options are unlocked, you will get a reminder to use a building that you haven’t used yet. But importantly, you’re not told exactly where or how to use it. Rather than feeling like a tutorial, it feels like an encouragement to constantly experiment. As the game gets increasingly complex, this does mean you’ll make mistakes. But since mistakes can be fixed, the game isn’t too scared to let you make these mistakes and recover from them.

I feel that the teaching is handled very delicately. Complex games often either fall into the habit of over tutorialising, or leaving the player drowning. Cities: Skylines perfectly walks the line, keeping players moving in the right direction without actually telling them what direction that is.

Starting complexity

When starting a new game, you first have to choose a map to build in. This immediately presents you with a lot of information. You get data on the resources available, how much water there is and how much usable land. It could be overwhelming, but a simple aesthetic choice helps here. Rather than using numbers, most of these quantities are shown as green bars, and even if you don’t understand what a resource means, you’ll be drawn to the maps where the green bars are big. Clever visual design helps to manage this very early complexity.

Once the game proper begins, you have a few things you can do, and a single goal: build a road and zone the land next to the road. With a little experimentation, you learn that the road building tool is very simple, as is the zoning tool. You will however soon learn that you also need to provide electricity and water, and pump away sewerage. So you really have five tasks here – roads, zoning, power, water and sewerage. Fortunately, you get occasional pop ups helping you with these early game tasks – letting you know about powerplants, water pumps and sewerage stations.

All of these things cost money, but you do start with a generous starting amount – plenty to get your fledgling city off the ground. Once you have your city basically stable, you will be given the ability to see your city’s economy in a different window. This shows you your income and expenses. When you unlock it, you are likely to see a dismaying fact – your expenses are likely higher than your income! That generous starting amount no longer looks quite as generous. This is concerning in the short term, but will come right as more people move to your town to spend money.

Once you’ve got your first few roads and zones set up and working, you’ll likely keep experimenting, adding more roads and zones. You also get the satisfaction of watching new buildings go up – a house here, a factory there, traffic moving back and forth between them. It’s very pleasant, but you may begin wondering: what are all these little blacked out icons? Well, you don’t have to wait long to find out.

Increasing complexity

As your population increases, you will hit various milestones over time. With each population milestone, new buildings and options become available, each of these slowly unlocking more complexity. I’m not going to go over the options from every milestone – there are a lot, and I haven’t even seen all of them yet – but I’ll go over enough of them to give a good idea of the increase in complexity.

The first milestone unlocks loans, the Medical Clinic, Landfill and Elementary School. Loans allow you to get a big influx of cash at the cost of increased weekly costs to pay back the loan. These are incredibly useful, as a number of buildings get expensive. Clinics and schools start introducing the concept of healthcare and education. An interesting thing to notice is that both the clinic and school have a range. At the moment you will likely only need one of each, but it’s clear that as your city grows you will need to think a little more about where you place these.

With the second milestone come a number of new possibilities. The first of these is the ability to buy a new area to develop in. You realise at this point that you will not be limited to the small square of land you start in, but will be able to expand. However, the most important thing that increases the complexity is policies: these allow you to set certain laws for your city that give both risk and reward – for example, giving out free smoke detectors costs you a few cents for every building, but reduces the likelihood of fires. Speaking of which, you now have the ability to build a fire house, along with a police station. This adds two new services to consider, once again with limited ranges.

With the third milestone, you gain a few new policies, the high school and public library as new educational options, and most importantly, parks. Parks allow you to increase the property values of an area, while also providing entertainment for the people who live and work nearby. Once again, we have been given another variable to keep track of.

The fourth milestone introduces a number of elements, but only one of them truly new – the bus depot. With a bus depot set up, you can begin creating bus lines for public transport. This is fairly complicated to set up – you have to lay out stops individually, and make sure that the route makes a complete loop, but setting up a public transport route makes citizens very happy.

From this point on, the increasing complexity is more focused on adding new options to already existing concepts. Roads with trees are introduced, which reduce noise pollution but increase risk of fire; high density residential and commercial zones, along with the office zone; hospitals and fire headquarters for improved service; Metro station as a new public transit option; universities for improved education.

Some of the complexity is also an emergent property. For example, traffic is never introduced to the game – technically traffic is a concern from the moment you build your first road. However, traffic isn’t really an issue until the population starts increasing, and by this time you already have some of the tools to improve things – wider roads, traffic circles and public transport.

All of this complexity – and it really is very complex – never feels as overwhelming as it might, because it is introduced very cleverly. By being drip fed increasing complexity, we are mostly comfortable with the current level of complexity before anything new is introduced. This also keeps players from getting complacent – it is difficult to fall into a boring loop, because the moment a loop becomes boring you are likely to get something new.

However, I don’t want to give the impression that it’s impossible to become overwhelmed – in fact, while taking notes for this analysis I did have a rage quit when everything was going wrong. But that was on me, not the game. Since I’d played before I tried to be cleverer than I needed to be. I was building facilities for a city far bigger than I had, and ended up with no money and demands that I couldn’t fulfil.

I had tried to run ahead of where the game had wanted me to be. This can be done, but you have to be better at these games than I am. For the average players like me, the designers perfectly paced the complexity so that you should never feel completely overwhelmed, and also never feel completely safe.

Pace of Progression

The pace of this progression is driven entirely by the population of your city – milestones that lead to more options come as your city reaches certain populations. This is a clever system – population makes for a good proxy of player success. Increasing population means that the city is running relatively well, and that there is enough space for people to occupy.

A big advantage of this progression system is that it is player driven, not time driven. If you’re struggling, or want to take time for your money to build up, you can do it, and the progression will keep pace with that. On the other hand, if you’re an expert and know exactly what to do to encourage optimal city growth, you can reach those milestones fast.

Gameplay Loop

It’s really quite difficult for me to identify a gameplay loop to this game, because it never felt like anything I did was the same as what I’d just done – it never felt like a loop. I’ll do my best though, because understanding the loop is important. For the first long section of the game, the loop looks something like this:

Lay Roads -> Zone Land -> Place Services -> Down Time

Once public transport is introduced, it increases a little:

Lay Roads -> Zone Land -> Place Services -> Lay Transit Routes -> Down Time

If you compare this to the gameplay loop from my previous analysis, you should notice two major differences. First, I haven’t marked any of these tasks as optional. In practical terms, they’re not. You may not need any medical services, but will instead need education; you may not need police, but will need fire. The range of the various services means that you’re always thinking of where you need these buildings.

The other major difference is that I’ve included down time in the loop. Down time is important to games, and it’s something this game does exceptionally well. Once a new district is set up and stable, you have some time to sit back and watch it. You may need to tweak a road or relocate a building, but you have these few minutes to watch your new district slowly grow and be filled, with low demands on you. This is a good contrast to the often frantic pace of building at other times.

Feedback

There is a lot of feedback in this game, and once again, it would be overwhelming if you got too much thrown at you at once. However, the feedback naturally keep pace with the complexity, since each piece of feedback roughly aligns with a feature you unlock. You get indicators of your weekly change in money and population. This is both numerical, and also in colour – green is an increase, red a decrease. There are also three bars indicating your citizens’ demand for residential, commercial and industrial zones. This is a good visual way to guide the player on what to focus on next.

You will also see small bubbles above buildings that have problems – lack of power or water, not enough customers for businesses, sick residents and many others. These can get overwhelming when things are going poorly – seeing a sudden wave of power outages when your power plant can no longer keep up with your growing population is a horrible feeling – but they serve as very good feedback.

Every time you reach a population milestone, you get a pop up telling you about the new milestone, the new services and buildings you’ve unlocked and – in a clever bit of visual flair – fireworks. It seems simple, but the fireworks function as effective feedback. This isn’t just another moment in the game, but a point of celebration. It is an achievement.

There is one more really important piece of feedback – visual feedback. A city that works well looks nicer. Seeing traffic backed up, with nobody moving, looks horrible; seeing the back up clear after you replace an intersection with a traffic circle looks much nicer. Higher property values make more attractive houses; huge areas of abandoned buildings from poor services drain the colour from the area. The visual feedback provides a nice way to get a handle on how things are going, although not nearly as clear as those mentioned above.

Positive Feedback Loop

The most direct positive feedback in this game comes from your income. When the city is running well, you will be collecting significantly more in taxes than you spend on upkeep for services, even when you have plenty of facilities. This means that a well-run city gives you the funds you need to keep the city running well – a textbook example of positive feedback.

The positive feedback loop goes the other way too – when you don’t have enough money for upkeep, you may find something of a domino effect – unable to maintain services for the current population, any new people moving in will strain that even further. At this point, you have to hope for negative feedback to save you.

Negative Feedback Loop

There is a very clever kind of negative feedback in Cities: Skylines. When things are going well and your city is thriving, more people will want to move there. This increases the demand for various zones, and as the city spreads, also increases the demand for various service buildings – new residents are still going to need police stations and schools.

Equally, when things are going badly, very few people will arrive and people will even begin to leave the city. While this does feel like failure, it does mean that the difficulty eases up at the worst times. Often it doesn’t feel like enough, but the game does need to keep some challenge. Using population change as a difficulty balance is a very clever way to handle negative feedback.

Goals

Cities: Skylines gives you constant goals to work towards. I have already spoken at some length about the population milestones, and the clever way that they help structure the complexity. These milestones also serve as your primary goal, and whenever you achieve one you can also see how far away the next goal is. This helps drive you, by keeping the next goal within sight.

There is another kind of goal, that I haven’t yet spoken about. There are a number of unique buildings, each of which has specific requirements. They’re often interesting buildings – a rocket launch pad, or the Eiffel Tower. These buildings are not at all required, but give the player extra things to work towards. The requirements range from having a certain number of universities to having a hundred thousand people live a full lifetime in your city.

The combination of these two types of goals makes sure the player always has something interesting to focus on.

Final Thoughts

Playing through this game again, looking at it more critically, has given me an immense appreciation of how well it is designed. The slow increase in complexity feels carefully thought out, the amount of downtime before demands rise feels expertly tuned and the constant small goals work incredibly well.

Anybody making a city builder, or a management game of any sort, could do well to look at this game and learn from it. We don’t need to copy them – nobody wins that – but look at the decisions they made and understand why they were made, and how they were implemented.

I’d love to hear from readers. If you’ve played Cities: Skylines, do you agree with my analysis? Are there any important parts of the analysis you would like to see me include in future? Speaking of which, next time I plan on going way back in time to an old favourite: Theme Hospital. See you then!