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CK2 Dev Diary #49: Mods and mod telemetry

Good evening, everyone. I’m Magne “Meneth” Skjæran, one of the programmers on CK2. In the past I’ve written dev diaries about modding, optimization, and quality of life improvements, and I'm writing this somewhat belated (due to technical issues) dev diary.

Today, I return to the topic of modding, and how we work to make life easier for modders. As a former modder, this is a topic I care quite a lot about.

If you’re anything like me, what you really want is statistics. How many people use mods, and which mods are the most popular. Luckily I come armed with exactly that.

As you might know, whenever you play CK2, the game collects some pieces of information about your setup. Things like what version of the game you’re playing, if you’re playing single player or multiplayer, what mods you’re using, and similar. This is all aggregated so that we can see overall trends and consider what areas might need some extra attention.

For mods, the main thing the telemetry provides is how many people use mods overall, and what mods these people use. My data will all be from users who played yesterday; anyone who during yesterday started the game with one or more mods is counted exactly once as a “mod user”, and counted once for each mod they used.

All told, 42% of everyone who played the game yesterday was using at least one mod. This could be anything from a small UI tweak, to a total conversion mod.
On average, anyone using a mod was using 4.24 mods. Once you start using mods, most people are not content with just one.
Further, here’s the 20 most popular mods, and how many percent of mod users (not overall users; multiply by 42% to get that number) that use them:
  1. A Game of Thrones - 45.4%
  2. Ruler Designer Unlocked - 30.2%
  3. Your Personal Castle - 24.9%
  4. Sketchy Cheat Menu - 18.1%
  5. CK2 Russian Localisation - 13.7%
  6. Historical Immersion Project - 11.3%
  7. A Sensible New Family - 10.7%
  8. CK2Plus - 10.6%
  9. Bigger Interface - 9.0%
  10. Purchase Claims - 8.8%
  11. Patrum Scuta - 8.6%
  12. Unique Buildings - 8.4%
  13. Novus Graphicus - 8.3%
  14. A Revolutionary Borders Mod - 8.0%
  15. Shattered World - 7.5%
  16. Korean SingleByte Patch - 7.2%
  17. CK2Plus - India - 7.1%
  18. Damascus Steel + Ancient Swords - 6.5%
  19. Better Looking Garbs - 6.3%
  20. Abdication - 6.2%
Combined, these 20 mods represent 60% of all mod usage. Since people who use mods on average use more than just one, it also adds up to more than 100% of mod users.

That AGoT comes first is unlikely to be a surprise to anyone; it has long been the most popular CK2 mod. Fun fact: AGoT is so popular, that its most popular start date is the 4th most popular overall startdate, after 769, 1066, and 867.

What is more interesting is that in the top 5 mods, two are “cheat” mods. Since they can’t be used in multiplayer unless everyone has them enabled, the idea of “cheating” doesn’t make all that much sense of course, and should instead be seen as achieving more of a sandbox experience than what the vanilla game provides.

Beyond that, there’s two localisation mods in the top 20; one for Russian language and one for Korean. The sheer amount of work that goes into translating an entire game is impressive, and it is great to see the modders’ work recognized to such an extent. Localisation modding is actually something we recently improved; in the 2.7 patch we moved custom localisation out of the “common” folder and into the “localisation” folder, meaning that it is now possible to use the custom localisation system without changing the checksum. This is especially important for languages with more complex grammar than English, such as the gender rules in French. The official French translation has for a while made use of custom localisation to change a number of words based on whether they’re referring to men or women, but doing similar in a mod would mean changing the checksum, making it impossible for the mod’s users to obtain achievements and play multiplayer with people not using the mod. This is something I know the Russian localisation mod has had problems with, and is a change I hope will lead to even better localisation mods.

There’s also a number of graphics and interface mods, plus several other mods that change the graphics or UI as a part of a larger package (E.G., the optional revamped interface in the Historical Immersion Project). People have done a lot of interesting things with the UI, but I know from experience it can often be somewhat tedious work. In the hopes of making it a bit less tedious, we’re making a console command that’s before only worked in the debug version of the game (which is not publicly available) available to everyone in a future patch (not 2.7.1). This console command is simply called “guibounds”, and what it does is that whenever you hover over a UI element, the area it covers is highlighted, and the name of the element, its size, and the file and line it is defined on is shown. This functionality is actually available in the release version of the game right now in a somewhat obscure fashion: if you try to open the console while on the main menu, it’ll be enabled. However, once you get into the campaign there’s no way to actually disable it since the console command isn’t available.
Below is an image showing what the guibounds functionality does:

There’s also a few large mods beyond AGoT in the top 20. CK2Plus even manages to take two spots on the list by including a mod that toggles the existence of India, while being pretty much tied with the Historical Immersion Project; some days HIP leads, other days CK2+ does.
The rest of the mods are smaller, adding small pieces of focused functionality.
Both types of mods we’re always trying to help by making the game more moddable. One changelog entry I think a lot of modders will find useful is this, which will be included in 2.8:
- Most effects and triggers that take a number can now take a variable name instead, and will grab the variable from the current scope. E.G., "wealth = test_variable"
This should allow mods to do far more interesting things with variables than is currently possible.

As a final note, modding is something we on the CK2 team take very seriously. Mods have the ability to add a lot of interesting alternative ways to play the game, and therefore helps keep the game fresh even for veteran users. In general, improvements to moddability also opens up new possibilities for our content designers, or can save them time by making their work simpler.
We’re therefore constantly considering how we can ensure new additions to the game are moddable, and we often go back and tweak existing functionality to open it further to modding.
We would love to hear your thoughts on what we could do better in this regard.
What, hows flogi's tech and buildings mod not in the list :O I meant compared to that your personal castle and unique buildings both made the list ;)

also is this new console command coming in 2.8 as well or even later considering you referred to the variable thing to be included in 2.8.
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Ruler designer unlocked in 2nd, maybe a sign the vanilla ruler designer point buy system might need to be less 'balanced' :p
Very interesting stats! Paradox is amazing when it comes to modding support and I am sure I can speak for most when I say we all look forward to how the mods and the base game can keep improving in the future! :D
I'm honestly surprised Ruler Designer Unlocked is that high (I didn't think anyone really used the ruler designer that much). I would have figured if anything HIP and CK2 would have had that percentage.

On a side note though, seeing how Patrum Scuta has a 9% following, I don't suppose that would convince Paradox to create some kind of high-res coat of arms DLC? I personally use the Maxson's HD Coat of Arms mod myself, which is basically the same idea.
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personally i love modding unit packs, its quite easy and provides much-needed variety
in the 2.7 patch we moved custom localisation out of the “common” folder and into the “localisation” folder, meaning that it is now possible to use the custom localisation system without changing the checksum.

This is a fantastic change! There are plenty of things in "common" for both CK2 and EU4 that really doesnt need to be in there, and I fully welcome the increased ironman modability, and hope EU4 gets a similar treatment for many of its cosmetic features *cough*cultural ruler titles*cough*dynamic province names*cough*
Great the dev diarys are back!
I just started to try modding the game few days ago, but I instant run in a hardcoded wall:
I made a test setup where I designate a particular Duke the regent as the HREmperor. But few day after the HRE needs a regent ( I gave the HRE the incapable trait) and the Dukes steps in as such, but shortly after another Duke or council member steps in as regent without warning or event showing for the former regent. What do I miss? There is no such event in the regency_events.txt where a random Duke or courtier/council member steps in as regent randomly without event message.

Note: I deactivated all DLCs and mods.
Is there any way to mod this away?
I really love when you provide us with statistics such as these ones or others related to our game practices (popular countries in EU, ethics in Stellaris...).

Have you considered making that information public and more systematic? I'm not talking about figures which could be used as a proxy to sales/users but in relative data in order to know more about our behaviour as a community.
Another fun fact that I didn't include in the dev diary:
Mod users is slowly climbing. Two weeks ago it was 38%, but yesterday it was 42%.

Part of the reason for this is likely that mods are still getting updated for 2.7. Another aspect is probably that some users go back to mods after having tried out the new vanilla changes for a while.
I just wanted to know whether the beta patch secret cults have been nerfed.
As shown in the statistic, Your Personal Castle and Unique Buildings are quite popular while not changing huge parts of the game. They are more about flavour than gamechanging mechanics.
Is there a possibility for your team to take this into consideration while planning out the next DLC?
I and many others would like to see something similiar included in the base game.