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Dev Diary 8 - Cities and Expansion

Hello everyone!

My name is Sam Minh Ly, a designer at Triumph in charge of the economy of Age of Wonders 4. In this dev diary I would like to talk about the economy and city development. Shoutouts to Glenn and Lennart who did a lot of work to design the systems of the economy in Age of Wonders 4.

Spoiler: There is a small teaser in the end of this Dev Diary, so make sure to read it till the very end!

Cities are at the core of your empire. They will use the surrounding land to provide you with the resources to raise armies, research Tomes of Magic and provide the mana to fuel your spells. They will also prove to be a good way to exert your control over the world. Cities lay claim to the surrounding area, making it difficult for enemies to come close without diplomatic penalties. And during war, cities are bastions that require a serious effort to breach.

City Income​

City Screen Crop.png

Let’s start off by explaining all the resources that cities produce.
Food is required to make a city grow in population.
Production is used to build city structures, which in turn provide resources or other benefits.
Draft is used to recruit units for your armies.
Gold is mainly used to build city structures and recruit units, but it can also be used in other manners, such as diplomacy.
Mana is used to cast spells and summon magical units.
Knowledge is used to research new skills from your tomes, which unlock new spells, units and more.
Imperium is used to further your empire as a whole. Its main use is for unlocking Empire Skills and acquiring new cities, but it can also be used to grow cities and in diplomacy.

Food, Production and Draft are all used in the same city that produced that resource, while Gold, Mana, Knowledge and Imperium are added to your global resource pool and can be used anywhere.

City Structures​

City Tree General Rersource Only.png

The primary way to gain more resources is by building city structures. There are four buildings for every resource and a well planned city can build all of these in a single city except for the Tier 4 structures, which are mutually exclusive. All structures have a gold and production cost, the latter of which determines how long it takes for your city to build that structure. You will see that all these structures have a boost requirement. We will cover that a little further in this dev diary.

City Tree Town Hall and Fortifications.png

In this diagram you can see a few different types of city structures. The Town Halls unlock new structures and special province improvements, which will also be covered later in this dev diary. A city always starts with the 1st Town Hall, providing a bit of a background income to get you started.

To the right of the town halls are the fortification structures. They provide Fortification Health, which determines how long it takes for enemies to siege the city before they can attack it. Many of them also provide an additional benefit during the actual battle, giving the defender an advantage in the fight.

On the left you can see the city stability structures. A city’s stability goes down as the town grows in size. You want to avoid your city to have a negative city stability.

City Tree Wizard Tower.png
Finally we have the Wizard Tower. Which is exclusively built in your capital, the Throne City. It provides empire wide benefits for your Godir. It is also the main way you can increase your Imperium income.

Building Queues
Queue Ration TT.png

Much like in previous Age of Wonder games, your cities can construct buildings which provide passive income each turn. Unlike previous games, the queue to build structures and units has been split in two, allowing you to construct structures and recruit units at the same time. This is paired with the new Draft resource, which is exclusively used for recruiting units. We made this decision so players could more easily bounce back after losing units in battle without destroying their city development progress.

When a queue is empty, it automatically starts to produce resources at a conversion % instead. Production is converted into Gold and Draft into Food.

City Domain​

City 4 Pop.png

Cities project a sphere of influence around the city called their domain. This domain extracts resources and ensures rival players can’t just enter it without consequences (more about diplomacy in a future dev diary!)

In Age of Wonders 3 and prior, this domain was a hexagon-shape that grew equally in all directions out from the city. This allowed it to exploit the natural resources of nearby resource nodes but gave the player no control. In Age of Wonders: Planetfall this was changed to a sector system, which resulted in player control over growth and more natural shapes that follow the environment. But these choice moments were few and far between and it was hard for many players to comprehend the impact of these choices.

Age of Wonders 4 uses a new province and expansion system. Provinces also follow the natural features of the world. They are smaller than sectors and unlike Planetfall you will gain a new province every time you gain a new population. Cities can easily get up to 15 population and 15 provinces, making your cities grow more organically in byte-sized chunks. This allows you to “steer” their expansion towards high value resources or to cut-off bottlenecks with your territory.

Province Improvements​

Annex Province.png

Whenever you annex a new province you can immediately choose what type of province improvement will be built here.
The choice of improvements depends on what features that province has.

Farms can be built on grasslands and provide 5 Food.
Quarries can be built on rocky terrain and cliffs and provide 5 Production.
Foresters can be built in forests and provide 2 Food and 3 Production.
Mines can be built on provinces with Iron Deposits or a Gold Vein and provide 5 gold.
Conduits and
Research Posts can be built on provinces with a Mana Node or Magic Material. The Conduit provides 5 mana and the Research Post 5 Knowledge.
Fisheries can be built on coastal provinces or in underground lakes and provide 5 Food.
Huts can be built when trying to settle in inhospitable regions, such as a frozen tundra or a scorching desert. They provide 3 Food and do not count as farms, which is important for other economic systems that we will cover further down. Choosing an adaptation allows you to build farms in those regions instead.

City Structure Boosts​

Library Requirement.png
Library Boost.png

For those that want to optimize their city development, we have the Boosting system which ties building city structures in your city to choosing new province improvements in your domain. Almost every structure has a boosting requirement in the form of specific province improvements. For example, the Library requires 1 Forester in a City’s domain to become boosted. If it is, the structure will require 30% less Gold and Production to build, making the boosts worthwhile to chase after and plan for when developing your cities and choosing province improvements. Of course higher tier structures require multiple Province improvements to be present.

Monolith Requirement.png

Building structures often unlocks more structures that are more expensive, but also provide more resources. Higher tier structures also require specific province improvements to be present in your domain. So you will need to make sure that the environment around your city can support a variety of province improvements and think about which improvements to build

Special Province Improvements​

As you progress through the game and unlock Tomes, you will acquire Special Province Improvements. These use the city construction queue, are often quite expensive and need to be built on top of any existing province improvement. But they provide more income than the basic province improvements, especially because they come with extra bonus income that is dependent on the type of adjacent province improvements, adding another dimension to planning your city.

Here are a few examples of what effects these Special Improvements can have:

The Mob Camp is an early game Special Province Improvement from the Tome of the Horde and fits with the Tome being about amassing an army of cheap units. It also allows you to set a province as a Unit deployment location, allowing your units to be recruited at the edge of your domain.

The Frostspire is acquired from the Tome of the Cold Dark. It benefits from the terraforming effects you get from the Tome and provides friendly visiting armies a buff for their next combat.

The Sanctuary specializes in another angle and instead provides defensive bonuses to your domain. Preventing enemies from pillaging and casting spells in the domain.

Capstone City Structures: Guilds​

Mages Guild.png

At the peak of your city's development are the Guilds, which are capstone buildings that provide a huge amount of income based on the number of province improvements of a certain type. For example the Mages Guild, the final mana structure that unlocks if you built all three mana structures before it. It provides 10 mana per Conduit in the domain! But only a single guild can be built per city. So you will have to choose what you want the city to specialize in. Of course this is dependent on the environment, so keep an eye out to the surroundings of your cities.

Faction Differentiation​

There are 6 cultures in Age of Wonders 4. Each with their own specializations in combat and in their economy. Each culture has multiple global bonuses that are unique to them which change how you play. For example, the Dark culture disables the negative effects from low City Stability, the High culture gains global bonuses based on whether you have a good, neutral or evil alignment. Aside from that, every culture gets unique units, Hero Skills, unique city structures and a unique Special province Improvement.

Let’s have a look at what the Industrious culture gets that other cultures don’t. Their unique structure after building a Tier 3 Town Hall is the Bastion’s Barricade. Which exemplifies Industrious’ aspect of fortification perfectly. It provides 20 Fortification Health other cultures can never get and the two Bastions are the strongest units the Industrious culture has, Tier 3 Shield units with immensely high physical defense.
Bastions Barricade.png

The Tier 1 and Tier 2 Food structures of the Industrious culture are replaced. Instead they gain the Workers Farmstead and the Grand Mill. Which provide less food than their normal counterparts but they also provide Production, which they normally don’t.
Workers Farmstead.png
Grand Mill.png

Their Special Province Improvement is the Builder’s Quarters. Which is a quarry that provides more production for each adjacent quarry. As you can see these bonuses can get really high if you get the right spot for them.
Builders Quarters.png

Now with all that extra production you can either continue to build high tier structures or you can use the Produce Merchandise option every city has. It normally converts 25% of a city's unused production into Gold. And while that is already good for the Industrious culture as their Production can become really high, they go even further. If you build their Tier 4 Town Hall, it not only provides the bonuses any Tier 4 Town Hall provides, but it also increases your Produce Merchandise conversion rate from 25% to 35%!

To wrap up this example I will give you an idea of what kind of synergies you can use to optimize your economy. As you might have seen in the Builder’s Quarters screenshot, there is a +2 gold bonus coming from something called Great Builders. This is one of the Society Traits you can choose when creating your faction. It itself combo’s really well with the Empire Skill Specialist Districts. Now your Special Province Improvements cost less Production to build and provide gold. The Materium tomes have many Special Province Improvements, some of which count as quarries, which will maximize the benefits from all these synergies.
Great Builders.png
Specialized Districts.png

City Cap and Automation​

Growing your empire by acquiring new cities is vital to growing your economy, but you cannot spam new cities indefinitely. If you over extend, you reach your City Cap. If you do so, every city in your empire will suffer a hefty -25% income penalty. This cap is meant to pace city acquisition and to stop rampant expansion. This will force you to either increase this cap via the Empire Skill Tree, or invest in your established Empire.

Another way to reduce micromanagement is the City Automation system. It allows you to set a focus (if any) and let the city grow on its own without having to choose every single province you can acquire.

For those that do want to micromanage and control their Empire in every detail, you need not worry. You can invest your Imperium into extra City Cap indefinitely, but it will cost you more Imperium each time.

Vassalization System​

And for both players we also have another way to exert your control over the world, namely the vassalization system. There are many Free Cities in the world that you can vassalize. If you do so, they will provide a portion of their income to you, depending on how strong your bond with them is. Moreover, you can decide to vassalize any city you conquer. These vassals do not count towards your city cap but they do provide you with income and a safe place to return to and recover between your campaigns. You can also integrate them later if you decide you want a particular city. Or you can vassalize your own cities directly to free up a city cap slot. Via vassals you can spread your rule over the entire world without limit.


There are many layers to the development of your city, which unlock as you progress through the game. The core loop of growth and immediate province exploitation is direct and meaningful. You can choose to engage with this in a casual manner but also choose to highly optimize your economy which is a necessity in the higher difficulty levels.

While there are other factors that influence your economy, such as the Society Traits and the Empire Skill Tree, this will do it for this dev diary. So, what do you think you will do? Plan the development of your city meticulously, go with the flow, or automate? or will you simply take cities by force? It is up to you to decide what path to follow.

While the next diary will be dedicated to the Ancient Wonders, there is also a new stream coming up!
We will let the community pick the faction, form, and tomes for our Developers to start with, so keep an eye on the Forum as we will let you vote next Wednesday!

Stay tuned for a new dev diary next week and consider adding the game to the Wishlist!


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Good information to have.

The one thing that jumped out at me, and it's a little thing: if "Blacksmith" and "Smiths Guild" provide Draft, then you've established that draft flows from metalworking. It intuitively follows, then, than a Mine structure built on an Iron deposit should provide Draft, not Gold.

If you want all mines to purely provide gold, I'd remove iron deposits entirely. Replace with silver or something.
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This is all cool, but the "draft" and "production" icons look very similar, and are only distinguishable by color unless you look closely at the sword vs hammer.

A simple and easy solution would be to simply flip the icon horizontally! Then the sword and hammer slant different directions and are distinguishable that way as well.
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I very much like the option to do things on your own or leave the city managed by AI. The system of integrating or vassalating cities due to your current needs sounds fun too. Thanks for the DD. Sounds great again. :)
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Another great Dev Diary! Many buildings to build here and 7 possible guilds. Nice.

Some intruiging things as well, like the Teleport province improvement unlocked by the Townhall IV and the Teleportation Circle. I wonder how that exactly works...
Or the Tower-cells where you can execute or convert a hero. What could be possible advantage to execute a hero if it gives you 2 knowledge per turn, I wonder?
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Thats a lot of vassals on the diplomacy screen, we've been told vassals can send armies to attack enemies, i wonder how that will look? Wars between players can potentially be huge.
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This is what I was waiting for, one of the most interesting parts of AoW for me. It looks like economy is theoretically simpler than in Planetfall, but I believe that if you consider the special province improvements and the fact that at least T4 economy buildings provide additional benefits, like seen in one of the screenshots, this might prove much more fun than it looks at first glance.

One thing however caught my eye: you can't improve draft through basic province improvements, only through city structures, special province improvements and, I suspect, ancient wonders. It feels to me a little like draft got the short end of the stick.
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An unrelated to this dev diary question: I've noticed that the game is being released on tons of platforms (which is great!) but I've yet to hear definitively if we'll be able to play cross-platform. Will that be an option?
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I'm wondering if there is an option to replace provincial buildings if I get upgraded version from the Tome or (like in one of the screenshot) I want to grow faster so I built farm on gold node and after a while I want to change it into the mine?
It was mentioned that special improvements have to replace existing ones but can you also replace the basic ones?
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So does food production eventually cap out then? I hope there is something to allow more druidic themed empires to use their food for something else if they have a max sized city.
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So does food production eventually cap out then? I hope there is something to allow more druidic themed empires to use their food for something else if they have a max sized city.
I've been wondering something similar, such as "Why would I ever pick a worker's guild now that unit production is separate?" it seems that production and food both can hit a maximum and then the question becomes what happens to that infrastructure? Can we sell the now excess food for more draft or gold or something?
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Thank you for this meaty diary! I keep thinking, ‘I can’t wait to play this!’ (Fingers crossed that I can handle the UI!)

I don’t remember if this has been answered previously: can we play as the vassal of another player? (I might be able to entice a particular family member to join in if I offer to play as a vassal).

This is even more niche: will I be able to use the hotseat feature to play several different factions on the same map? I’m a rotational-household Simmer, and I even enjoy rotating between dynasties in CK3. I’m already dreaming of several different factions I’d love to play in rotation! :po_O:D

Edited to add my thanks—I was so focused on my questions I forgot my manners! :oops:
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Can you replace the exclusive Tier 4 buildings if you later want to re-specialise your cities? What about province improvements?
Also, does the Worker's Farmstead only have one worker, or is that a typo?
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Everything about this I love! It's a clear evolution and upgrade from AoW3 and PF, I love how much more there's to the city building and adding the "sectors" ontop is great! All the changes to them, making them smaller and less significant is great, it was always the case of certain sectors and each one at the start being a major decision. I'm excited for all the special improvements and little min-maxy stuff with placing certain things in certain positions and the boosted system. It's a great system to get someone like me who usually isn't all that into city building in a 4x get excited.

That alongside the basic structures not requiring building queue and building being separate (as we've known for a while) really make it feel more dynamic. It's that traditional 4x or turn based thing that's there, and people, even I, argued there's a reason for it such as making a decision, but ultimately I think it just gatekeeps the genre, particularly in MP.

Opening it up makes it easier for people to get into it, it's simpler, there's already enough significant decisions to be made in a 4x that I don't think this matters and I hope way more such games adopts it. It feels more akin to an RTS, where building and queuing stuff in said buildings are separate things. It'll make the game feel less sluggish and put less emphasis on production, which tends to be the king of resources for this limited reason. It still will be king, but it may even the scales more.

Other than that, big fan of the vassal and city cap system. It adds to the more empire building side which AoW haven't been that known for, but I think AoW4, whilst still heavily combat focused, does tickle that side a lot more and the management and limitations, adding a layer to the rest of the game than just commanding armies and conquering.

I will say though, as a major advocate for the free form traits, that I think you should add an option to remove city cap. Personally I want city cap to stay as the vision for the game and future titles as I love the strategy the mechanic introduces, but it's a new change, and just as I think we should be free to play with whatever form we like but leave the option to limit oneself if they want, the people who want to play the game like the previous titles, expanding rapidly and microing a ton of cities, the option should be there for them as a toggleable setting.

I think it's a fair middle ground as I've already seen some people worried about this new system. It remains to be seen how limiting and hard it'll be to push the cap or going over the cap, but I've always been of the opinion that any game can never have too many sliders and checkboxes to allow people to tailor their game to how they wanna play it, especially a 4x game.
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Glad to see that you took the sector system and even improve it. Love it on plantefall. I liked to make choices while thinking on how to build my cities considering the terrain i got :D

Limitless, at a cost, city cap is good to have but makes me wonder how much useful it can be and how people will play with it. Perhaps some people will vassal cities while waiting to increase their city cap. While others leave it low only vassal cities and improve what they got with that imperium :)

Gotta wait to play the game when it's out to see that myself :D
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