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Hello and welcome back to another EU4 dev diary! Today, as promised, we’re going to be talking about our design process.


Originally, Johan was the sole designer on EU4, taking design input from team members but ultimately making the design decisions himself. Those of you who have been paying attention during the last year may have noticed both that EU4 has gotten more popular, and that the design process has changed somewhat since the start of Res Publica, being more of a divided responsibility between Johan and Martin (Wiz).

Johan has had a funny role in the project as he is technically not part of the team, but has been working as lead designer, writing a majority of the design for the expansions, and have also programmed a fair bit on the project. So far, 17,5 years of EU development, and he won’t let it go just yet.

While Johan still makes the big decisions, Martin handles the day-to-day design decisions such as feature implementation, numbers tweaking and handling the input from the team. The rest of the team currently includes 3 experienced programmers and 1 scripter, and a QA team of 4 QA that give great input on the design. We also get a great deal of design input from our beta testers, several of which have experience going back all the way to EU3 and earlier. We also have an internal email group where we get feedback from the various people at the office that play the game religiously.

Though we accept a great deal of input from the team, from beta testers and from the community, EU4 design is not by committee. There is a clear hierarchy, with Johan at the top having final say. Nonetheless, there is a great deal of trust and flexibility in the team, with Johan trusting that Martin will follow the spirit of his design vision, and Martin in turn trusting developers to do the same. More often than not, if a developer raises concerns with a design while they are working on it, that design will then change, as it is impossible to consider all problems and angles when you’re writing a design document. A number of features have radically changed during development because a developer said ‘This won’t work’ or QA said ‘This isn’t fun’, and entire features have simply been cut when they didn’t work out quite as planned.

Design is mostly written in two-man meetings between Martin & Johan, where we tend to throw all sorts of ideas around to see what sticks. Of the two, Johan tends to be the visionary who comes up with the sweeping ideas, while Martin does the majority of the work refining said ideas into the final design that ends up in the game. These meetings tend to spawn a lot of ideas for future expansions, and we also use them as a means of solving balance problems in the game (‘let’s sit down for 10 minutes and figure out how to fix the economy’). Even when we don’t achieve everything we want during the meeting, it usually sets the gears in motion, and if we notice we’re not getting anywhere we’ll just stop the meeting… and usually, 15 minutes later, one of us runs over to the other with the solution to the problem.

We try to set a concept or setting for each expansion a long time in advance, and then design features from that concept. Common Sense, for example, was nicknamed the “religion & government” expansion, while Art of War obviously was a “war expansion”. At present, we have such outlines for a further 5 expansions, and no shortage of ideas even beyond that.

We keep a document of how the features for an update (expansion+free patch) should work, and we keep this up to date during the development, as we focus on having short and clear design documents. These documents are sometimes made years in advance, as we add ideas and features we come up with in our creative meetings.

Finally, and this is where we think a lot of game designers go wrong, we actually play our own game. Both Johan and Martin play EU4 in their free time, with thousands of hours of playtime between them, and QA plays even more, with Jake (DDRJake) and Carsten (ForzaA) currently having a bit of a race to 100% achievement completion (which ForzaA is currently winning).

As to where we get our ideas, there is no single answer, so to top this dev diary off, here’s a few examples of features in the game and how they evolved. Hopefully it will give you an idea of how we get from idea to implementation.

Fortresses and Zone of Control - This started as a post in the beta forum, with the usual complaints about carpet sieging, and how forts should be more important. At the same time there was a thread in the public forum about how good the March of the Eagles combat with forts were, which basically had forts. From there, Johan wrote the design. Though a lot of details had to be tweaked (garrison sizes, ZoC functionality, etc) the design originally envisioned was pretty much the same as what eventually got released in 1.12.

Government Ranks - This idea originally came out of an EU3 mod, and is something Martin has been wanting in the game for a long time. When Common Sense was being designed, we needed a few more features (we have a ‘value’ breakdown for each expansion to ensure that the number of features in the expansion match the price point), and Martin threw together a quick pitch that was added to the design.

Development - This was something we debated on quite a lot, as Johan came up with it as a way to let players build tall, but Martin had problems with combining the development system with the old buildings system (as you’d then have two competing ways to develop with monarch points) , and suggested a completely different development design whereby you’d develop building slots instead of bt/production/manpower. After a lot of discussions, Johan combined the two into a final design that tied building slots to development, ending up with a design that (in our view) was better than either of the original proposals alone.

Nation Designer - This is an idea that a number of people have proposed since the release of the CK2 character designer, but the actual outline for the design was spawned late one tuesday night at a Gyros place, when Martin and Henrik (Groogy) from CK2 were getting some post Tuesday beers food before going home. Martin suddenly had the idea of a nation designer where you created your borders by clicking on the map. From there, he bounced a number of ideas off Henrik, and sat down the next morning to write a design that was later accepted by Johan. The actual implementation then fell to Rickard (r_lazer), the senior programmer on the team, who spent more than a month on it in continuous discussion with both Martin and Johan.

1.8 Map Expansion - The massive map expansion for the 1.8 patch accompanying Art of War came about when Johan came out from his office and said ‘I want 1000 new provinces in the rest of the world’. This was partly due to the experience of playing competitive multiplayer as Ming, and finding the experience there more dull when it came to actually fighting wars compared to the maneuvers in Europe. From there, it was a massive project involving Johan, Martin, Henrik (Trin Tragula) and at least a dozen betas. Martin was originally a bit skeptic to the idea of adding so many provinces, but Johan did the optimization work needed to make it work, and Henrik (who was hired mid development) played a crucial role directing the work of the betas, who did most of the heavy lifting on the actual map.

So! That was a lot of words about making EU4 design. I hope it’s been enlightening as to how we work, and if you have further questions, don’t hesitate to ask in the dev diary forums thread.

(If anyone is wondering about the third person perspective, it's because me and Johan co-wrote the post)
 
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It's great to get insight into Paradox. Other than the fact that they make games, they do just feel like a passionate,well motivated SME trying to be distinct in a comepetitive sector. They consistently punch far above their weight.

Thanks for sharing Wiz.
 
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Will one of the 5 expansions tackle trade and trade flow? Everything moves to europe, even if I manage to build an empire in India and crush the puny europeans. With the introduction of development you can now make any part of the world full of rich provinces, but the trade direction is still locked.
 
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Why refer to yourself in the third person Wiz? :p

Serious question tho: Are there any ideas/features that were going to be added, or thought about, but ultimately scrapped for whatever reason?

Preferably ones that we dont know about (tho, i dont know of any!)
 
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Any chance of a further development of combat mechanics?

That being ways to improve generals by combat experience; possibly even traits (combat ability vs. Heathens, Rebels, Muslims etc).
 
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Will the Low Countries be reworked and boosted eventually?

Also maybe someway to give personality to generals and admirals. Maybe a lot of won battles and campaigns lets you build a monument to them.

Maybe a sort of end game museum thing where you see all yor accomplishments, important people, and memories.
 
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Neat.
 
Will the Low Countries be reworked and boosted eventually?

Also maybe someway to give personality to generals and admirals. Maybe a lot of won battles and campaigns lets you build a monument to them.

Maybe a sort of end game museum thing where you see all yor accomplishments, important people, and memories.

Maybe if each General gained Army Tradition and Admirals Navy Tradition, we could simulate experience.
 
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17.5 years? Damn, I was part of EU1 beta, when I was young... 17.5 years old? Are you sure? Looking at mirror, seeing grey on temple... Damned again 17.5 years...
But hey, I'm a software program manager in my office, and I started working on this productin 1996 during my internship, and Im still managing that, with other products now

So that's 19 years. Beat you!
 
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I was just thinking, an expanded Army/Naval tradition mechanic would be great.

Over time, one should unlock modifiers for their army and navy. We can retain the current army/naval tradition by making it into a modifier for these army/navy 'traits'.

So for example, if you pick a trait +10% Infantry Combat ability, at 10 army tradition it will only return a meaningless 1% infantry combat ability. However, if you keep your tradition high, you'll get closer to your full bonus.

Generals and leaders shouldn't just be a lottery for 6/6/6/6. They should have the ability to improve their stats by winning battles or sieges. The average time for this happening should be very low for 4/5 star generals but you should be able to train by 1 or 2 pips some 0/1/0/1 general through winning battles or sieges.
 
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I was just thinking, an expanded Army/Naval tradition mechanic would be great.

Over time, one should unlock modifiers for their army and navy. We can retain the current army/naval tradition by making it into a modifier for these army/navy 'traits'.

So for example, if you pick a trait +10% Infantry Combat ability, at 10 army tradition it will only return a meaningless 1% infantry combat ability. However, if you keep your tradition high, you'll get closer to your full bonus.

Generals and leaders shouldn't just be a lottery for 6/6/6/6. They should have the ability to improve their stats by winning battles or sieges. The average time for this happening should be very low for 4/5 star generals but you should be able to train by 1 or 2 pips some 0/1/0/1 general through winning battles or sieges.

Would be a good way to add personality to your military to show if you want to dedicate more to land or sea.
 
when Johan came out from his office and said ‘I want 1000 new provinces in the rest of the world’.
Haha, i love how such a game changing feature was added because Johan got bored while playing as Ming.
 
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So i have some things that i would like to ask, but I'll not because of various reasons. I will however ask one question

So the current fort mechanics require you to siege down a fort before you can move past it. in most circumstances, this is alright. there are a few things that can happen that make the system look bad, but it is passable imo. Now to my idea. So forts under siege do not have enough influence to retake your own land while they are under siege. but they somehow have enough influence to stop 50k army from coming by with a 2k garrison that is trapped in/near their fort. That seems odd to me. i would propose that if a fort is adequately under siege with the proper number of troops, an army can pass by without having to worry about it's ZoC. Now the besieging army may not pass through, just to clarify. Only another army(s). This would make forts better in depth, and allow attackers a way, albeit costly depending on the amount of layers, to get to the provinces/armies in the rear.

Thoughts?
 
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