With strong sales, positive reviews (ours is here), and thousands of player-made assets and mods, Cities: Skylines has quickly become one of 2015's hits. I spoke to Mariina Hallikainen, CEO of developer Colossal Order, over Skype on Wednesday, and asked her about the origins of Skylines, 2013's SimCity, mods and modders, and plans for the future.

PC Gamer: Considering that you set a Paradox sales record at launch, you've sold a half-million copies of Skylines, and that both the reviews and the reaction from players has been almost entirely positive, can I assume your offices now actually resemble the massive Colossal Order skyscraper that's in the game?

Mariina Hallikainen: [Laughs] We're still in the same office, we moved over here just last January so there's no need for anything too different from that. We're of course very happy. We're very pleased.

It's pretty common in discussions about Skylines to see 2013's SimCity being brought up. While it sold well, it's clear a lot of people were disappointed with some of the choices Maxis and EA made. When Skylines was being developed, was SimCity something that was discussed often at Colossal Order, and was there an effort to deliberately avoid some of the same choices they made?

Yeah, that's a tricky question, because of course, we always have thought of SimCity 4 as the benchmark. This is due to the fact that we actually did plan this game when we started the company back in 2009. We started to think about... Colossal Order wanted to make a city builder some time in the future. We knew we couldn't do it right from the start because we were five people. I started the company with no experience on the PC platform. The guys had been working on mobile before Colossal Order. It was really something that ideas kind of came from, really, the classic city builders.

But of course we were extremely afraid that people will just think of us as a cheap knock-off or something, that we have been just trying to copy what they did in SimCity. So it was a little bit of a daunting task for us. But of course there are things that are very similar and I guess it's kind of unavoidable in a sense that the city building genre, I think, it's based on the great SimCity. So it's something that we knew we would be compared.

Was Skylines already actively in development when the 2013 SimCity came out?

It was not actively in development at that time. When they announced [SimCity 2013] I was pretty sure there was no way we would ever be able to convince Paradox that we should make this game. [Laughs] But, yeah, they gave us the green light after they saw what happened with SimCity.

So that was actually... seeing SimCity 2013 kind of stumble, that's when Paradox said, hey, maybe we should go ahead with this since people aren't really happy with the last SimCity?

Yeah, I think it must have helped a lot.

Now, when I was playing Skylines pre-release, some people knew I was playing it, and one of the questions that most of them asked was, is there a multiplayer mode? Did you consider any kind of multiplayer for Skylines at any point?

No. Basically, we are of course with very limited resources and with the small budget we have, it was completely out of the question. Even if we think about... we have a certain philosophy behind the game, and it is definitely so that it is really a singleplayer game. It's you creating your own city, your own world. You don't want anybody to kind of come and mess that up. The experiences we've had previously, we decided that we will go singleplayer only, at least for now.

Yeah, I'm not even really sure how multiplayer would work. I think there's a collaborative potential, its fun to sit with someone at the same computer and build a city together, and our guy Tom was streaming the game a few times last week and he had fun with the people watching, taking suggestions and things, but I don't really know how a multiplayer city builder would work with two people messing with the same city at the same time.

Yeah, that's exactly the problem, I think, and especially because there's the simulation running, there's so many things that can go wrong, I think it's something that you really have to put a lot of effort and a lot of people to work on that, to make it really work and be right, and so we definitely didn't feel that it was important to do at this time. And, I don't see it as a high priority feature at any time in the future, because there's still so many things we want to add to the game. We have quite a lot of plans, those things we couldn't implement before the release, like tunnels and European buildings that we are working on now. I think there's a lot of things we want to add to the game before we can even discuss multiplayer.

So you do have plans for future updates, or is it a DLC type thing?

So, basically we have discussed it with Paradox and it's going to be a similar model to what they have for Crusader Kings 2 and Europa Universalis 4, so it's a bigger expansion with some smaller DLC and also free content. The tunnels and the European buildings we already discussed that these would be free updates, because I very strongly feel that the tunnels, for example, should have—I feel it's a part of the game. It's an integral part of the game and it needs to be there. So, we agreed that we, of course, having only 13 people working at Colossal couldn't make it in the original scope, we really just want to add that later on, and I think it belongs to all the players.

You compared the future expansions to what Paradox does with CK2 and EU4. Those are, a lot of times, different parts of the world or different time periods. Is that something that Skylines is going to have?

No, it's more to the scope. Basically, how we did it earlier with Cities in Motion, for example, we had smaller DLC and we were working on those, but here we want to kind of focus on one bigger feature. I can't say what those are exactly at this time, but we are planning on something that really brings something new, hours of gameplay to the game. So, massive expansion.

I can't say more about the pricing but it's something similar to what they have done with CK2 and EU4. Simultaneously with this we add free features and free content to the players who already own the game. So, the players who don't want to put any money to extra content, they still get something out of the version. This is what we're planning, there's always like this bigger expansion that will bring a lot to the game, then the free updates as well probably [smaller] DLC. But it will be so that it comes with a full package that has all of this, the paid and the free update for the player. Which I think is really nice, because we get to focus on something more major and then also there will be the free update, because I think it is important that the players who have bought the game now and for some reason don't want to, for example, put any money to a certain expansion, they can kind of pick and choose what they want but still get something, something like updates to the game so you don't have to pay for absolutely everything. I think that's very cool.

Are there any plans for a terrain editor you can use while you're actually working on a city?

We have discussed that. There is no news about that yet. So, basically—terraforming has been actually discussed quite a lot. It is a little bit of a tricky feature so we need to think about it a lot to see if it would be possible or not. We have some ideas. We'll keep you guys updated on that

Given the successful sales of the game, do you think that's changed the scope of future expansions? Do you feel like you have a little bit more room to grow because the game has sold well?

Well, [Paradox] is very happy. [Laughs] It is something that we have discussed that now we have a chance to add more to the game both in the scope of the planned expansions and for the free content as well. One of the major differences now after these really massive sales—it's still a little bit overwhelming for us over here—is support for the modding. So, we're basically discussing that we really want to emphasize that, we want to bring more to it, so we definitely got more support, also from Paradox to work on that, which is absolutely fantastic.

I checked this morning, and there's over 13,000 player-made assets and mods in the Steam Workshop at the moment. Have as anyone at Colossal Order been trying them or playing with them or seeing what people have been up to?

Yeah, I mean, we've been checking what's happening there and it's really, really great to see, because last time I checked it was 12,000. [Laughs] So, the number keeps going up. It's absolutely fantastic. I think this is exactly what city builders are all about. It's about the creativity, getting the people to join the development of the game, and I think this is absolutely wonderful to see, so many people actually joining the modding community, and yeah, we've been checking. There's actually really, really cool stuff. We have been checking out the different kind of mods, too. Because there are so many things that we kind of planned to do later and the modders basically already did them. So, we have to say a little bit... are we needed anymore? [Laughs]

Right! Yeah, there seems to be a few things in there that you could possibly officially add in a future patch. People have been... one of the first things they did was unlock so you could build on all 25 tiles. And then a few other things that look like they could be possibly incorporated into an official patch at some point.

Yeah, absolutely, there's so many things to choose from, but I think most interesting ones are kind of those that... like the GTA V map, there's the Mars project. So much creativity, and you know, things that we couldn't kind of think when we entered this project, that people would come up with these kind of ideas and I think that's exactly the great part about this. Because we're only 13 people here, but there are so many ideas out there, so many capable people that can really contribute to this game.

I even saw there's a former Maxis artist who's making mods for the game, have you seen that yet?

Yeah, I saw the article on that, yeah. I think it was on PC Gamer, actually. Yeah, yeah, um. [Laughs] I mean, it's really, really great to see people starting to create content for the game and we of course welcome... [Laughs] welcome really capable environment artists to do that as well. So, it's really interesting to see.

We keep suckling on Cities: Skylines news teat, because a) it's good, b) it's doing well—having just broken the 500k sales mark—and c) it has mod support, and so has a community that's consistently pumping out great stuff.

For instance, right now on the Steam Workshop you can find a couple of buildings from Bryan Shannon—a former Maxis employee who worked on both SimCity and its expansion, Cities of Tomorrow.

Whatever you think of SimCity—and I know what you think, I have read the internet—it was a beautiful looking game. That's reflected in Shannon's buildings, which fit nicely into Skylines' aesthetic while experimenting with its look.

"Overall, this coal power plant is a deviation from the original style," writes Shannon of his coal power plant. "This asset introduces a nice dirty brown brick in to the game's overall neutral palette."

You can see Shannon's Skylines buildings here, and see the work he did for SimCity over at his blog.

Update: Shannon is now on Patreon, taking pledges to fund his work inside of Cities: Skylines.

Cities: Skylines is being pirated, but Paradox Interactive isn't panicking. Instead, the publisher will continue to support the game, thus making the Steam version more attractive than any unpatchable and unmoddable pirated version could ever be.

Taking to Twitter, Paradox's Sham Jorjani made a case for post-launch support being the best discouragement for pirates. Noting a steep 16 per cent increase in pirated copies of the game, Jorjani Tweeted that "our plan for pirates is to make a great game even better through free updates - making it more convenient to use Steam instead."

"It's all about offering the superior service," he added. "That's how we bring down piracy. By making the paid experience a superior one."

Jorjani went on to name Netflix as an example of convenience trumping piracy in the digital age. Meanwhile, Paradox's quick rollout of Magicka updates 14 in 13 days meant that users preferred to actually pay for the game and get auto-updates, rather than manually download the game each time the studio patched it. 

To put it simply: ongoing content rollouts and mod support is a better way to combat piracy than DRM.

"Or....we could build our own ecosystem," Jorjani joked. "Call it....P-play....or...Plorigins...or P-vapor or somesuch...yeah let's do that."

Cities: Skylines has already attracted a massive audience: modders have already added a first-person mode, while one dedicated player has recreated Los Santos.

Not even a week has gone by and the Steam Workshop for Cities: Skylines is already bursting at the seams with player-made content. Along with maps and buildings created using the game's editors, mods have begun to appear, most notably one that lets you unlock all 25 map tiles. The vanilla game lets you use nine, which is still pretty roomy, but why limit yourself?

The tile unlocking mod is hard to make a full column out of, however, so here's one you might also want to check out: the free camera mod.

It's described as a first-person camera mod, but it's really more of a noclip mode, allowing you to fly through the city unrestrained, drop down to street level, zip between buildings (or through them), and basically check out your creation from any spot you like.

Got a problem in your city? Don't be an aloof mayor, coldly sitting in your office in the sky. Go check it out in person. It's the least you can do when your citizens start complaining about traffic or taxes or garbage collection or, I dunno, that their houses are submerged in sixty feet of water. You know, the kinda stuff people just have to gripe about.

Once you subscribe to the mod, you'll need to activate it in Content Manager menu. In the game, you'll now see a button in the top right corner of your screen. Click it to bring up a settings window, which lets you set the speed you want to move at and how close to the ground you want to get. Move around with WASD. Tab returns you to normal mode, or you can configure it to another key.

Obviously, your city wasn't meant to be seen from quite so close up, so it's not exactly pretty, but it's still a neat tool and useful for getting a closer look at things. For instance, what's going on at that bus stop? Clearly, there's just too much novelty food truck traffic to let the bus through. Get on it, mayor!

I think the game's regular camera is fine for the most part, but it can occasionally be tricky seeing things up close since it bounces over buildings, trees, and hills, so the new camera is a nice addition. I even loaded up a save from the diary I did this week, to get a close look at one of the more disturbing events that took place.

You can find the mod here in the Steam Workshop.

PC gamers can't actually play Grand Theft Auto V yet, but thanks to the efforts of Steam user grockefeller, we can pay a visit to the friendly city of Los Santos, which he has recreated—along with Palomino and Sandy Shores—in Cities: Skylines.

Man, that was fast.

Cities: Skylines was not a game I expected to be a hit, but it came off quite well in our review, and even more importantly, people are buying it and doing some amazing things with it. This mod lets players take to the streets to appreciate the fruits of their urban planning labors from a first-person perspective, for instance, while this weirdo created an entire city in which only one, single home could be built, and then spent days spying on the family that moved in.

The Los Santos reconstruction is a project on a somewhat larger scale. The mod description says it's "the completely built region of South San Andreas including the cities of Los Santos, Palomino, and Sandy Shores." Note that in order to actually use it, you'll also need the separate 2x4 parking lots mod, and unlimited money to cover the city's debt, which is apparently significant. As grockefeller succinctly put it, "It was expensive."

I like to imagine that city building games are already first-person; just that the person in question is an invisible floating omnipotent sky-mayor. A mod for Cities: Skylines offers the more traditional first-person view—albeit one from what appears to be an improbably tall citizen.

The mod allows you to explore the streets of your city. It's a simple camera switch, but one that offers an interesting perspective on your city's simulated citizens. It would have certainly let Chris L get down-close-and-personal to the occupants of his single-house city.

Below you can see the mod in action. If you want to try it out, head over to the Steam Workshop.

City-building sim Cities: Skylines has become Paradox' most successful game launch, selling 250,000 copies in its first 24 hours. The number—tallied from day one sales and pre-orders—has made CEO Fredrik Wester quite happy.

We would like to offer our deepest and heartfelt thanks to the community for their passionate support and to let them know that we are committed to supporting this wonderful game for years to come, in much the same way that we have for our Crusader Kings and Europa Universalis communities," he sends in a statement.

"We knew that we had a great game on our hands and so to be able to continue to provide fans of the game with a multitude of new content for it going forward is fantastic.

The inclusion of mod support should certainly help Skylines' longevity. There are already more than 3,400 mods hosted on the Steam workshop page, including one that lets you wander around your city in first-person, and another that adds a convenient autosave function.

That's lovely to see, because Cities: Skylines is really good. Find out why in our review, and enjoy the strange cocktail of humour and sadness hidden away in Chris L's diary about his city with only one house.