1. Hearts of Iron IV
  2. News

Hearts of Iron IV News

Dev Corner | Hydrodynamics

[p]Last week's Dev Corner can be found here, but let's begin the next one!


[/p][h3]Briefing: Hydrodynamics[/h3][h3]Written by: Zwirbaum[/h3][p]
Hello everyone!

Another week is upon us which means it is the time for another dev corner. Last week Thomas talked about what we are cooking with the Factions, while I will be talking about naval and naval-related changes. Even the most beautiful placeholder art will be gone eventually like tears in the rain. So strap in, and prepare for the deluge of the information that will be coming your way. Also, keep in mind that everything discussed here is in a relatively early stage, and as such is subject to change.

It is no secret that one of the most common sentiments across the Hearts of Iron IV player base is that the Navy seems to be rather hard to understand. Some elements are almost instantaneous in the effect (Supremacy), others take a long time (building the Navy) and some elements remain relatively hidden until the actual shooting starts (Supremacy Value of the Ships, Screening in Taskforces etc.). On top of that we are also having a fairly complex system of Naval Missions - where they work best when using them together, synergistically. However missions could be explained a bit better, and sometimes what is best to achieve your goal could be somewhat counter intuitive. (Giant Strike Force of Doom, sitting idle in the port somewhat projecting supremacy across the entire oceans without ever sailing out as one example). So how are we planning to address it?

[/p][h3]Core Concept[/h3][p]Similarly to how last week we talked about high-level concepts for the Factions, I will try to do the same for the Naval Systems, but before that I will also list some of our goals that were the basis for what we are working on:
[/p]
  • [p] Updating and Reshaping Naval Gameplay, making it more strategic, giving you the opportunity for the counter-play if needed; a bit more predictable, and less ‘flip-floppy’
    [/p]
  • [p] Updating Naval Missions so that they become more intuitive, with a much clearer purpose and use case
    [/p]
  • [p] Encourage a more active use of fleets
    [/p]
  • [p] Update and Communicate better to the Player some of the intricacies of the Naval Systems
    [/p]
  • [p] Increasing the Importance of the Islands Control (in the Pacific) and Naval Logistics
    [/p]
  • [p] Updating Carriers and address the interactions between land-based aircraft and naval taskforces
    [/p]
[p]
[/p][h2]Update to Naval Gameplay[/h2][h3]Naval Dominance[/h3][p]First of all, and the most important of the changes is that we are introducing the concept of Naval Dominance. Naval Dominance is a sort of umbrella term for a couple of things. Similar to how ships had Supremacy Value, now they have Naval Dominance Value, which will be displayed on the Ship Card.

Mutsu has 509 Naval Dominance Value. We are also changing the old calculation, that was based mostly on Production Cost and Manpower, to have more things affecting the calculation, like Speed and Range, so for those who want to build Fast Battleships, increased dominance value may be the reward…

Next, we will want to talk about Naval Dominance - which is our way of indicating naval control of sea zones. Each Sea Zone, depending on the terrain type, has a certain threshold of dominance points you need to have before you can claim you ‘control’ it. And if you are at war, then similarly to the older system, you are also taking into account enemies' Dominance Value and the ratios between you and them. Also the ratio needed for ‘control’ now has been adjusted to require 66% instead of 50%+1.

Having control, or as we call it now, establishing Naval Dominance in a Sea Zone, provides you with certain advantages and bonuses. For instance, as you can see in the screenshot below - potentially reducing the amount of convoys needed for Trade and Supplies by up to 25% if you have secured the entire shipping route.
There are other benefits that I will not fully reveal yet, but amongst other things, there will be something to help you secure islands and potential naval invasion targets.

In this example we can see that in order to claim ‘control’ over the Deep Oceans sea zone, you would need to accumulate at least 1000 points worth of Dominance, assuming nobody would contest you.

[/p][h3]Dominance Gain[/h3][p]This tooltip shows the information about the current amount of dominance accumulated in this sea zone, how long it will take to establish its full value, things that impact it, like airbases located on the islands in the sea zone etc.

Dominance as opposed to the previous supremacy system now takes some time to establish, but it also doesn’t simply instantly disappear when ships engage in combat, or go to repair after a battle.

[/p][h3]Naval Mission Updates[/h3][p]We will also be making the following changes to Naval Missions. We will divide current missions into 2 groups; Core Missions and Auxiliary Missions.

Core Missions - (PATROL, CONVOY RAIDING, CONVOY ESCORT, STRIKE FORCE)

Those missions are your primary way to interact with naval dominance. Each mission type will interact a bit differently. As it is right now, Patrol will be serving for Building Up Dominance, Convoy Raiding reducing Enemy Dominance, Convoy Escorts will provide a ‘protected’ value, which means enemy raiding won’t be able to reduce your dominance below that value, and Strike Force serving as a ‘Synergy Tool’ - and amplifying other missions. Hopefully this will provide a clear and relatively intuitive system on how to use the Naval Missions.

Auxiliary Missions - (NAVAL EXERCISE, MINELAYING, MINESWEEPING, NAVAL INVASION SUPPORT)

Those missions do not interact directly with naval dominance, however, they do benefit from it, like for example, being able to minelay or minesweep faster and more efficiently when operating within a region where you have established control and have naval dominance.

[/p][h3]Naval Home Bases, Range & Supply[/h3][p]This Dutch Fleet has set the port in Batavia to be their Home Base.

We are reintroducing the Home Base system for the Fleets. Each Fleet needs to have a Home Base. Any Naval Base that you have access to (Your own, Subject or Faction Members, or if you have secured Docking Rights) can be selected as a Home Base. So the question is; what does the Home Base do?

[/p][h3]Naval Range[/h3][p]One of the changes that we are doing is that the ship's range is now projected from the Home Base instead of all Naval Bases.

As you can see depending on where Home Base is located, the range, and access to do the Naval Missions is quite different. A fleet with Königsberg set as Home Base does not have the range to do the missions in Norwegian Sea or Western Approaches Sea Zone.

[/p][h3]Naval Supply[/h3][p]Previously, naval units would always draw the supplies from the Naval Bases closest to where the taskforces were operating, now - they will be drawing the supply from their selected Home Base.

This fleet has a Home Base set in Honolulu - and is operating in the Micronesian Gap. Despite the port in Johnston Atoll being closer it draws the supply from Hawaii Naval Base Supply.

[/p][h3]State Building Limit - Islands[/h3][p]In Götterdämmerung we introduced terrain-based limits for province-based buildings like Forts and Coastal Forts, so that you couldn’t build the Maginot Line everywhere. In a similar spirit, we will be introducing state-based building limits for the buildings. In this case we are now focusing on putting limits on the various Island categories, so that not every single tiniest of islands can have an airbase capable of storing and launching for missions 2000 planes every day. Right now those caps are based on the Island state categories (Tiny Island, Small Island, Large Island), and upon one concept we will talk about in the future.

Marcus Island can now have at most a level two airbase and level three naval base. Those limits as all the numbers, stats and values are of course subject to change. Also there is totally nothing hidden under that Hearts of Iron IV logo.

Short Comment
Initially when I started writing this section, I was going to write how I envision things mentioned so far will change the naval gameplay, and how X will impact Y, however I think I am more interested in hearing what you, my dear readers, are thinking and your opinion on what you have read today.

[/p][h3]Naval Invasions[/h3][p]We are doing some touch-ups to the naval invasions as well. In the current live version of the game, there is a global naval invasion capacity set by your technologies, doctrines and other modifiers, and then depending on how many divisions you assigned to the invasion, it would take a certain amount of time to plan that naval invasion. This system unfortunately had one issue, that in order to be ‘optimal’, it encouraged to spam 1-division naval invasions, as that technically allowed you to have a massive naval invasion planned just within a few days, at the small cost of carpal tunnel syndrome.

In the new system, there will be, depending on your technologies, doctrines etc. a certain amount of naval invasions you can plan at the same time, each being able to have a certain amount of divisions, and no matter what, always taking a specific amount of time to plan.

Also, for a country that hasn’t researched even the basic Transport technology, there will still be a possibility to launch a very limited naval invasion under the new system.

[/p][h3]Appeal to my Lizard Brain[/h3][p]And last but not least, I’m going to tell you about one more thing - and that is that we are adding visual representation of control over the seas, visible on default map mode, which during a conflict should represent a gradual shift of control over the zones, giving the feeling of ‘naval frontlines’. Also this can serve as a kind of warning, that when your coastline sea zones start displaying your potential enemy colours.

This is the current prototype of showing on the default map mode who has naval dominance. In this case Japan has the most dominance, and nobody is effectively contesting it, thus Japanese colors are displayed on the map.

[/p][h3]Wrapping Up[/h3][p]So, to wrap things up, this is just a number of things we are doing for the Naval. I have not touched upon anything Carrier related, new equipment or new tools yet, or any UX/UI updates. I will return in due time to provide you with more information on all the things that are not-dry, in the meantime - here is a teaser of a thing that we may talk about in the future, with this beautiful placeholder art done by myself.

Who will guess what this is?

This is my first dev corner, so I can only hope my writing is not too stiff. In time I hope it will get better.

Anyways, thanks for reading and until next time, farewell!

/Zwirbaum




Also, we have a survey for you to fill out when/if you have time regarding Naval Gameplay. Just keep in mind that this Steam thread is for your feedback about the Developer Corner. If you have feedback about this specific survey we welcome your thoughts in a separate forum post, or in the HOI Discord!

EDIT 25/06/25 - Thank you to all participants for the Player Survey, this survey is now closed!

Click the Image above or this text here to fill out the survey

[/p]

War Effort | Patch 1.16.9

[p]Generals!

We return with new intel from Command, a new War Effort is now live with balance and gameplay tweaks, UI and performance changes and a bunch of bugfixes, make sure to read them all below;

[/p][h2]Balance[/h2][h3]Afghanistan[/h3][p]- The focus Socialist Coup can now be bypassed if they are already communist, and the coup can be performed peacefully if there is more than 60% communist support in the country
- Countries will be more likely to accept your Confederation with Pakistan if they are in the same faction as you
- The focus Reform the Quami now grants an additional 10% recruitable population factor
[/p][h3]General[/h3][p]- Removed hostile armor speed factor from German Blitzkrieg operational planning modifier; this modifier only half-worked by virtue of a bug that has now been fixed
[/p][h2]Gameplay[/h2][h3]Afghanistan[/h3][p]- Mohammed Daoud Khan now becomes a general if going down the Nufus branch
- Added a focus to the Quami branch that allows for the production of cheaper, but less efficient rifles
- The army branch now contains two focuses relating to utilizing Camels in the military, with one of the focuses requiring Battle for the Bosphorus
- Added a focus to the industrial branch to expand the Spinzar Cotton Factory, granting two more civilian factories
- Added a focus accessible to the non-aligned/democratic branches about constructing a national identity, gaining strong bonuses after some investment
- Added new focuses to the Nufus military branch, to gain a larger army, and potentially seek mutual guarantees with Turkey[/p][p]- Added a strong capstone focus to the Nufus branch that references the historical title of the Royal Afghan Army; Prussians of the Orient
- Added 4 new political advisors
- Added Traditionalist Paths to the Against Kabul Branch
- Added three new low-probability expansionist AI Strategy Plans
[/p][h3]France[/h3][p]- Improved the description of the focus "Fatherland"
[/p][h3]India[/h3][p]- Added a news event for the formation of the East India Company
- Added a news event for the Royal Indian navy Mutiny when India flips communist
- Added a news event for the Death Knell of the Raj
[/p][h3]General[/h3][p]- Overlords capitulating now always gives half progress to next autonomy level, disregarding of which autonomy level it currently is

[/p][h2]UI[/h2][p]- Fixed an issue where army composition summary in frontline tooltip would show incorrect information
- Added the option to disable map corner scrolling while keyboard navigation remains enabled
- Added hotkey for accepting diplomatic requests quickly by Shift + Left Clicking top bar alerts

[/p][h2]Performance[/h2][p]- Improved multiplayer save file transfer speed significantly, which should help resyncing to be much faster than before

[/p][h2]Modding[/h2][p]- Added "after" (as opposed to "immediate") effect scope for events

[/p][h2]Bugfix[/h2][h3]Afghanistan[/h3][p]- You will no longer lose your own core states when gaining Tajikistan or Turkmenistan as allies when declaring war on the Soviets after having completed the focus "Alliance with Turkic Peoples"
[/p][h3]India[/h3][p]- Pakistan and Bangladesh will no longer be counted as Princely States that break away from the Raj when declaring war as the Mughal Empire after having completed the focus "Revolt of the Princes"
- Fixed an instance where UK could swap India communist by completing decolonization while a dynamic india tag existed
[/p][h3]Iraq[/h3][p]- Muhammad Amin Zaki now correctly becomes available if you complete the Encourage Federalism focus
[/p][h3]Turkey[/h3][p]- The turkish focus "Taking over Defense of the Gulf" will no longer allow Britain to transfer states it does not own and control to Turkey
[/p][h3]United States of America[/h3][p]- Fixed an issue where America could not flip fascist because a decision was hidden
[/p][h3]General[/h3][p]- Fixed an issue where installing modules did not play sound effects when MTG was disabled
- Fixed issue where random character names would not apply to modifier tooltip
- Fixed tooltip showing wrong country in naval combat
- Fixed laws not applying to revolter in civil war
- Fixed an issue where alternate icon settings would inadvertently revert to default settings
- Fixed an issue where Diplomatic Pressure would be set to zero after reloading a game
- Fixed an issue where having the Diplomacy window open would highlight the International Market icon in the top bar
- Naval Aircraft MIO archetype now actually adds Naval Attack / Naval Targeting / Sub Detection and Surface Detection to their planes.
- Changed display of matching MIOs in production line creation from "available / total" to just "total" due to obsolete differentiation
- Fixed an issue where generals could be displayed as belonging to the wrong nationality in the Battle window
- Fixed an issue where the custom rule for Maximum Fort Level would not be applied correctly
- Fixed an issue where strait highlighting could get stuck when switching from the navy map mode
- Targeted decision cancel_effect will now execute if the target is invalidated but also happens to be a valid country with no provinces, this should resolve various issues with targeted decisions such as European Union invitations locking themselves into an invalid state
- The Suez Canal will no longer display an unlocalized string in its tooltip after being blown up
- Prevented dynamic state modifiers to speed from a) setting their value instead of adding, and b) applying twice. This resolves issues with certain mechanics such as Ethiopia's Decentralization system setting unit speed to 1km
- Sweden can no longer trade ball bearings with a country it has embargoed
- When the East India Company is formed while India is a subject of a nation other than the UK, Britain will no longer become the overlord of the Raj
- Fixed an issue where switching Trade Law to Closed Economy would not always cancel all active exports
- Fixed issue with ship weather penalty reduction also reducing positive modifiers (this will mostly affect destroyers - by quite a lot)
- Foreign countries (usually Japan) will no longer lose control of British Malayan territories if they transfer allegiance to Australia through the Australian focus tree
- You can now correctly load heavy cruisers from persistent equipment designs
- You can once again upgrade MIO on basic equipment if you chose not to upgrade it automatically
- Added 30 days of sanctuary from changes in autonomy level after recent change
- Made sure MIO selection window closes properly when switching between equipment designer types
- Observers can now always see the combat log of the observed country
- Fixed an issue where swapping production lines to licensed equipment would keep any MIO assigned
- Fixed an issue that would cause auto-design to apply MIO to licensed equipment
- Fixed an exploit that allowed licensed equipment being turned into owned tech
- Fixed a CTD in multiplayer when a client was building railways during a hotjoin




[/p]

WW2 strategy game Hearts of Iron 4 is giving factions a fundamental rework

Hearts of Iron 4 has just celebrated its ninth birthday, and the WW2 grand strategy game remains the most popular of its type on Steam, reaching highs of more than 50,000 active players on a near-daily basis. Yet developer Paradox clearly still has ideas for how to keep building on its core; 2024's Götterdämmerung expansion delivered big changes to central players in the conflict such as Germany, Austria, and Hungary. Now, in a new developer blog, the studio explains that it plans to overhaul the way HoI 4 factions work.


Read the rest of the story...


RELATED LINKS:

Before Europa Universalis 5, get Paradox's finest grand strategy games cheap

Hearts of Iron 4's next DLC is adding weird WW2 experiments sooner than expected

New Hearts of Iron 4 DLC finally expands Central and South Asia in the WW2 game

Dev Corner | Reinventing Faction Dynamics (Part 1)

[h3]Generals![/h3][p]Continuing from where we left off last week, we have another briefing from Command. Find a comfortable chair, settle in, and read on.[/p][h3]
[/h3][h3]Briefing: Reinventing Faction Dynamics (Part I)[/h3][h3]Written by: Wrongwraith[/h3][p][/p][p]Hey all,[/p][p]Dev corners are back. What are they and how do they differ from the Dev Diaries we normally do? The key difference is probably the scope. Dev corners are usually shorter. Here we discuss things that are sometimes very early in development, whereas Dev Diaries are usually about describing and explaining the new features that come with an expansion. So less details, and also a lot less pretty screenshots. And above all, a lot more Work in Progress - the things we talk about here might not even make it into the game in the end - at least not in the shape they are presented.[/p][p][/p][p]But enough of that, on to what I was supposed to talk about. Today’s subject is Reinventing Faction Dynamics…[/p][p][/p][p]Not much has happened to factions since release, so we figured it was time to take a look at them. The main difference is that there are more of them as more countries can, and do, create factions now. But in general they are all very similar, and you don’t feel any difference playing as the Axis as opposed to the Allies, the Comintern, or the Chinese United Front - for example. The goal here is to change that. To make factions feel more unique, and immersive at the same time. [/p][p][/p][p]Before we continue I should reiterate that this is very early stages - so not much in terms of final UI is implemented, sometimes you can’t do things except by commands, and in general things are constantly changing - so don’t expect pretty pictures![/p][p][/p][p]But look at it from the bright side - you get to see very early UX mock ups - and some beautiful “coder art” :) [/p][p][/p][h2]Core Concepts[/h2][p]Today I will try to run you through the core concepts of what we are doing with factions. Later on I will dive deeper into details, but for now, I’ll try to keep it relatively high level and give you the big picture of what we are working on for this feature.[/p][p][/p][h3]Faction Manifest[/h3][p][/p][p]Early mockup of Faction Window Header - showing the Manifest, the Faction Icon, and the Faction Power Projection[/p][p][/p][p]Each faction has a manifest. The manifest is about what the faction wants to do. Conquer new land, Stop the spread of fascism - or similar longer term purposes. 
[/p][p]Each manifest will have a percentage of fulfillment - that can go up or down during gameplay. If the fulfillment is high enough, some bonuses will unlock - depending on the type of manifest.[/p][p][/p][p][/p][p]In-game view of the Faction header with manifest for the Allies - this is as raw as a screenshot will get. Placeholder art, no tooltips, no graphics added, and no attention to placement or final elements. But it is there, and it is working, and as the Allies, we want to defend democracy[/p][p][/p][h3]Faction Goals[/h3][p]In addition to the Manifest each faction will have shorter or longer term strategic goals. These can be things like conquest of specific territory or control, or instigation, of resources..

These goals, once completed, will give the faction members rewards that they can use to modify their faction in various ways - as well as more standard rewards like Army Experience. [/p][p][/p][p]Together with the Manifest, the Goals will give the faction a direction. A direction you need not follow if you don’t want to, but if you do you will be rewarded.[/p][p][/p][h3]Faction Types/Templates[/h3][p]All factions are based on a template. So when you create a faction you pick which type of faction it is from those available, and then you get a set of rules and goals etc to go with that. Factions created through a focus or event will have their type pre-defined. So setting up a faction shouldn’t require many more clicks than previously, but still give you a few options. And most importantly result in different experiences based on what you play as.[/p][p][/p][h2]Rules[/h2][p]Each faction comes with a set of rules. These generally relate to a specific action type. Like for example who can join the faction or who in the faction can declare war.[/p][p][/p][p]Some examples: [/p][p]A rule for joining can be based on the ideology of the joining country. For example, the rule might state that only non-fascist countries can join. (It won’t prevent a country from turning fascist later though). Another Joining rule can be based on Geography, saying that only countries from a specific region can join.  [/p][p][/p][p]Other types or rules relate to things such as: [/p]
  • [p]Peace Conferences - Giving you bonuses to certain types of actions[/p]
  • [p]War Declaration - Who can declare war and what are the requirements[/p]
  • [p]Call to war - Who can call to war, just the faction Leader, anyone, or Just Majors etc[/p]
  • [p]Dismissal - When can you kick someone from the faction[/p]
  • [p]Contribution - What are the minimum requirements for contribution to the faction[/p]
  • [p]Leadership Challenge - What are the requirements for taking over leadership  [/p]
[p][/p][p]There will probably be a few more, and some of these might not make it, but you get the general idea. [/p][p][/p][p]These rules can be changed during gameplay, if the Faction leader, or any other member country, has Faction Initiatives available to do so.[/p][p][/p][p][/p][p]UX mockup for changing your Rules (in this case the Join Faction Rules) [/p][p][/p][p]Speaking of Faction Initiatives - lets move on to:[/p][p][/p][h3]Faction Initiatives and Goals Rewards[/h3][p]Initiatives are what you use to change things in your faction. These Initiatives are gained from completing Goals. Most goals will give one Initiative to the faction leader when completed. Some might give to other members as well. And if you have an Initiative to spare, you can change a rule. Or you can remove one. Or add one - it is basically up to you to decide what to spend your Initiative on, and how to modify your faction. But choose carefully, for initiatives will be few. (Which also means you won’t be spammed with decisions to make - which is something we want to avoid.)[/p][h3][/h3][h3]Other ways to spend Initiatives[/h3][p]Apart from just changing the rule set for the faction, you can add specific upgrades to your faction to make it more unique. [/p][p][/p]
  • [p]Example of upgrades you will be able to do are: [/p]
  • [p]Adding or improving Research Sharing [/p]
  • [p]Adding or improving Military Doctrine Sharing [/p]
  • [p]Adding a Faction Supreme Commander[/p]
  • [p]Start up joint research sites[/p]
[p][/p][p]UX mockup of the research part of the Factions screen.[/p][p][/p][h3]Influence and Contribution[/h3][p]The last thing I want to talk about today is Influence and its close relative; Contribution. [/p][p][/p][p]Each member Country has an Influence rating in the faction. This is basically an internal power level - how important a member are you within the faction?[/p][p]Countries with high influence get more things from goal completions. Meaning they will also have a say in how the faction evolves - as some of these rewards can be Initiatives. [/p][p][/p][p]Additionally, in order to take over leadership of a faction you need to have a minimum level of influence. [/p][p][/p][p]You gain influence by War participation, Contributions, Industrial might, and from “Events”. Events can be various things depending on the faction and the content - but can include things such as executing daring Raids, or from focuses or decisions. [/p][p][/p][p]Of these, Contribution is probably the most interesting to talk about. Basically whenever a country delivers something to the faction, or to other faction members they gain “contribution score” - which is directly reflected in their influence rating. Whenever someone receives contributions, or “withdraws” from the faction pool, they lose contribution score - thus lowering their influence. [/p][p][/p][p]This means that Influence will build up and fluctuate over time. [/p][p][/p][p]Another use of influence is in peace conferences. When your faction is on the winning side, all member countries will pool some of their war score, and this will be given to the most influential countries in the faction. Similar to the game setting where the Faction Leader can get part of other members’ scores. But here it is not just the faction leader, so if you are an important part of your faction, you will get more say in the peace deal even if you are not the faction leader. [/p][p][/p][p]What are contributions then? [/p][p][/p][p]Generally they are things you can do to support your faction or your faction members - such as sending expeditionary forces, pooling manpower for use by the faction, producing industrial goods, Lend lease to faction members. Those kinds of things. Some of those we already have in the game, but the goal is to streamline them a bit. Others are new - but regardless of whether they are new or old, they will contribute to your contribution score - thus making you more (or less) important in the faction. [/p][p][/p][h3]Some Final Words[/h3][p]Another thing we want to add when working with factions, is the ability to tell your fellow allies where you want them to focus their efforts. Similar to how you can create pings to multiplayer allies, you should be able to tell your AI allies that I want you to focus on this region. It shouldn’t mean that they abandon everything else, but rather just increase their attention here.  [/p][p][/p][p]That was all for this time. I am looking forward to hearing your thoughts, and I’ll do my best to answer questions, but do bear with me, I won’t be able to answer everything - party from a time perspective, but also based on the fact that there are quite a few things that are as yet undecided, or at least relatively untested - so I might not know what the end result will be. If it doesn’t play out fine, or smooth - things will change. But I will do my best. [/p][p][/p][p]Additionally, I hope to be able to give you a few more details in a few weeks time - because as you can see I if you look at the draft schedule presented earlier, I do have yet another slot for this. [/p][p][/p][p]And as I said, what you have seen here will most certainly differ from what will eventually make it into the game. It takes many iterations, and a lot of feedback to get a feature completed. But I hope you enjoyed this little peek into what I/we are doing at the moment. [/p][p][/p][p]/Wrongwraith[/p]

Hearts of Iron IV Anniversary week & Developer Corners!

Generals!

Not only is our nine year anniversary happening today, but we've got a lot of content for you all to read through so make sure to continue reading. We've got Developer Corners starting up again, HOI4 Anniversary Giveaways every day and the Multiplayer Mayhem happening in the 2025 Community Cup!

But first, a word from our Commander in Chief Arheo.

Greetings all,

As the oft-quoted Eisenhower stated, "In preparing for battle, I have always found that plans are useless, but planning is indispensable”. In the spirit of this, we thought it would be time to take a look at the long-term roadmap for Hearts of Iron. It has been around three years since our last formal Hearts of Iron Roadmap, and while plan have changed and evolved, this statement of intent has been largely what has guided our development process up until the release of Götterdämmerung.

Our mainline intended innovations, when this was written just after No Step Back, included the following:

  • Improvements to Frontline Stability (Progress in NSB, more to come)
  • Strategic and Tactical AI improvements
  • Battle Planner Improvements


Götterdämmerung included a lot of improvements to the AI including Force Concentration: a feature designed to simulate tactical pushes and armor concentration. This has been an interesting one: when released, we saw a lot of players taken by surprise by the AI using this approach, and a lot more discussion over players being defeated or losing to the new AI behaviour. However, most of the community seems to have adapted fairly quickly to this change. To me this is a positive thing: while having a broad playerbase with varying levels of skill means we need to be gradual about how and if we increase overall difficulty when playing against AI, the existence of community “meta” and learning materials gives most players tools to catch up. In short, there’s no reason not to continue iterating on AI features that may increase average difficulty or required skill levels.

On a related note, we’ve fixed a bunch of issues with frontline stability, but battle planning remains a tool that has a stark divide between how new and veteran players utilize it. We’ve done some quite deep user research into this particular area, but this resulted in few actionable results beyond handling edge cases better and improving frontline integrity.

[h3]Long Term Goals and Strategies to Guide AI (Progress in NSB)[/h3]
Most of this is “under the hood”, but we’ve made a lot of progress adding tooling to interpret and direct how the AI performs long-term planning. This area of the game is notoriously opaque and it’s taken a fair while to get to the point where we have enough analytical insight into the mechanical decision-making process of the AI, but, we’re more or less there now. This has meant improved tooling such as AI strategies, imgui debug tools that modders also have access to, and better integration with existing mechanics that previously existed “on top” of the game without interacting much with the AI. This is of course a goal that has no defined end-point, but compared to where we were three years ago, much has improved.

[h3]Improving Peace Conferences[/h3]
By Blood Alone saw a contribution-based peace conference system added, with numerous narrative demand options. On reflection the design approach here was not super stable, and while the feature hit most of the key notes (contesting demands, earning defined contribution, rewarding better play), it fell into a similar trap to the old system when it came to AI antagonism. It took longer than it should have done for that behaviour to stabilize with tweaks and changes, but we’re in a better (if not perfect) situation now.

[h3]Update Core National Focus Trees with Alt-History paths alongside more Options[/h3]
We’ve had a couple of methods of doing this. First are the maintenance updates included in some War Effort patches. These tend to be quite minor, but we’ve added a fair few things to various focus trees over time.

Secondly, revisiting focus trees such as Germany and Hungary represents a greater investment into this. Overall, I’m happy with the dual-pronged approach to this; reworking focus trees comprehensively is a full expansion-cycle affair, and doing it outside of a paid release is not something we will ever be able to do. I feel the majority of the community understand this, and our roll-in approach to DoD, TfV and WtT has been for the most part welcomed.

[h3]Great Power Diplomacy[/h3]
I’ve spoken at length on this in a few other places. Fundamentally, design ideas for this one always ended up conflicting with focus trees. HoI4 is a war simulation with a superimposed latch-driven state-machine that drives the global narrative. It is unlikely we’ll change that approach. However, the process of working through design ideas for this has given us some avenues for further exploration.

[h3]Multiplayer & Social layer Improvements & Support[/h3]
The Career Profile and associated features hit the social layer note pretty well. Traditionally, these features are designed to increase player engagement: something which HoI doesn’t really have an issue with. However, the feature has proven to be unexpectedly popular amongst specific groups within the community, both for completionists and as a learning aid. While I don’t think we’ll be making any fundamental additions to this, it won’t be going away and we’ll keep adding content such as new medals and ribbons.

[h3]Economic Decision Making[/h3]
We haven’t made any great strides here. We still have medium to long term plans to expand the industrial economy elements of HoI, while taking care to avoid simulating too many pure economic elements.

[h3]Special Projects[/h3]
Götterdämmerung represents the culmination of this project. I’m pretty happy with how this turned out, though now that we’ve had some time to monitor the wider effects of special projects, it is about time to revisit balance and take a pass on the huge array of tech that was added in the Götterdämmerung update.

[h3]More Difference between sub-Ideologies & Government forms, Advisors and Internal Politics Improvements[/h3]
We didn’t really get here! This is quite a difficult topic to broach in a strategy game, and other things ended up taking precedence. We’ve had some minor changes to advisors, but nothing to write home about in the grand scheme of things.

[h3]More National Focus Trees[/h3]
Fairly Self-explanatory.

[h3]Make Defensive Warfare more Fun[/h3]
This is still a goal of mine, but we haven’t managed to tackle it yet. I think some of the fundamentals of HoI4 (ie, stuff we simply can’t/won’t change) stand in the way of doing this justice, though it also plays hand-in-hand with changes to doctrine and division design which are definitely in the works.

[h3]Adding Mechanics to limit the size of your Standing Army, especially post-war etc[/h3]
Definitely still planned, though not a major priority on its own - will have some words on this later. I don’t feel like this is something that has been glaringly missing for a game with a narrative of “crescendo to war”, though as we start to experiment around the fringes of that pillar (smaller regionally-focused conflicts and expansions), it will become more necessary.

[h3]Have Doctrines more strongly affect Division Designing[/h3]
We’ve had some success here with the changes to support companies and equipment streamlining. I wouldn’t go so far as to say this is “done”, though. We have short-medium term plans regarding doctrines though, and having them affect division design more strongly is one of the key pillars for this effort.

[h3]Immersion and Roleplay Elements, Optional tools for making your mark in a Game[/h3]
We’ve added a lot of things that touch on this: division medals, plan naming, deeper recruitment design, MIOs and industrial specialization being chief among them, feature-wise. I think these features do what they set out to do: letting you leave your own mark on the battlefield and the campaign narrative. As you may have noticed from recent war effort patches, we’ve also identified that we need to be better with streamlining how players interact with these types of features.

[h2]War Effort Updates[/h2]
I talked at length in the 2022 roadmap about the introduction of maintenance updates - something we ended up doing, and calling “War Effort” patches. On their own merit, these have been extremely useful for us, and have allowed us to iterate and introduce quite a lot of system updates and quality of life changes such as:

  • Persistent equipment designs
  • System Rebalances to designer modules and units
  • MIO streamlining
  • Some quite significant performance improvements
  • Over 1000 bugfixes
  • Mod support
  • Focus tree updates
  • Balance standardization of some systems (quite important for game health!)


One of the things we were uncertain of before we started War Effort patches was whether this would reduce the maintenance included in major updates, resulting in effectively just moving things around. With the exception of our approach to country packs (ie; not including maintenance updates at country pack release), it has not directly affected the size and impact of major releases.

The old Roadmap championed these as a method of updating older focus tree content. It’s fair to mention that this ended up not being a major focus of war effort updates. It became quickly apparent that developing focus trees is the majority of the work our Content Designers do; that’s not realistically something we can do in iterative updates.

So while there is success here, there’s also room for improvement. We will keep producing War Effort updates, but I want to try and find some form of structure to them, and a way of steering them in a way that more quickly addresses high impact community issues. Particularly, I would like to find a way to increase the visibility of our approach to handling community issues, though I will caution that this will require some time to achieve.

[h2]Next Steps[/h2]
Aaand that’s our retrospective.

That ended up quite a lot longer than I’d expected, but that’s ok - the future plans are at least a little more concise! I want to give you an updated roadmap for our next few years, though with the usual caveats. As you can see above, these plans are not super specific, they aren’t promises, and they don’t always work out. Nonetheless, the act of planning is extremely important, and communicating those plans perhaps even more so.

So what does the future look like for HoI4?

It will come as little surprise that South/East Asia is next, with content primarily focused on Japan and China, and mechanics to support this narrative, as well as reinvigorating the Pacific war. I don’t want to go into too many specifics here (tune in next time for more!), but the war in and around Asia as well as the Pacific has been left behind by our recent developments directed at the European elements of the conflict. To give some broad strokes here, we’re looking at developing the narratives that faction membership will give you, improving and streamlining elements of naval control, with a particular focus on the types of naval warfare that carried the Pacific conflict, and adding much greater strategic narrative (and a less opaque simulation) to the flow of naval conflict. This is not an exclusive list, and it’ll probably leave you guessing - but you won’t have to wait long.

In the longer term, we have some other areas that we’re keen to take a pass on:

[h3]Military Doctrines and Division Design[/h3]
These systems are quite old and don’t offer much ability to shape your gameplay. I would like to link these better, in order to have doctrines shape both how you compose and how you use your military.

[h3]Manufacturing and Inustrial/Economic Gameplay[/h3]
Watch this space.

[h3]Breaking the Snowball![/h3]
HoI’s “crescendo to war” that I mentioned earlier is extremely important to the main narrative of the war. However, as time goes on we have released more content focusing on the smaller players in this conflict. There are elements of the game that don’t mesh particularly well here, and I want to take a look at the way wars and war escalation are structured to make this more engaging and less disruptive when minor conflicts erupt.

[h3]Improving the Diplomatic Landscape[/h3]
“But you said you couldn’t do this!”, I hear you cry. And mostly you would be right. However, with the introduction of late game technologies in Götterdämmerung, there is even more reason to continue playing after the end of the war. I would like to keep developing how the world “falls out” after the conflict, producing more realistic geopolitical results as well as the potential for new and more systems-driven “what if” conflicts after the end of the war. Of course, any such changes would be multiplied in effect if they could also touch upon the pre-war landscape too…

[h3]Alt-History[/h3]
Well, that’s a broad category. This is one we’ve been looking at in quite a lot of detail. We see an increasingly stark divide within different groups of the community on how we (or even if we should) approach alt-history. For those that enjoy it, don’t worry, we’re not going to stop making alt-history content, however, I have asked the team to look, in the long-term, into ways of producing more structured, plausible alt-history content with clearer historically-adjacent narrative hooks. In addition, we have started to evaluate if it’s possible to create more deterministic global alt-history situations and produce some “semi-alt-history” ways of playing HoI - something that I think would capture the fun parts of the non-historical content we provide while also retaining the benefits of the determinism that the historical scenario imparts.

I have one, final note on the practical elements of what we release. We intend to continue releasing what we’ve previously termed “Country packs” and “Unit packs”, but we need to both be clearer about what is or isn’t included, and adjust the scope. We’re devoting some more resources to our Country pack development moving forwards, and we’ll be including mechanics and systemic changes in those the same way as expansions - albeit still focusing on “minor players” in the war.

Alright, I started writing this three hours ago and apparently I’m still going, so here I will force myself to stop. I’m here to answer questions.

/Arheo

Of course, these dates may be subject to change so keep that in mind!

[h3]Hearts of Iron IV's 9th Anniversary![/h3]
As apart of HOI IV's Ninth anniversary, we've decided to do another giveaway with a different prize each day including some fan favourites and some keys for the new Song pack for those of you who missed out on some of those banger tunes. To participate and enter for a chance to win some of these codes, make sure to reply in the announcement post on each day you want to take part in the giveaway.

Because of time zones, we've decided that each giveaway "day" will start at 14:00 CEST, so for example, if you want to take part in the Bonus Songs Pack giveaway on Tuesday, then you need to reply between 14:00 CEST on Tuesday and 13:59 CEST on Wednesday. If you reply on Wednesday 14:00 CEST, then you're taking part in the Wednesday giveaway, etc.

You can reply as many times as you want, on as many days as you want, but if we're looking through replies and have to choose between two replies, we will probably choose the reply that has some substance (vs "Just replying to take part") so be creative, engage, comment on the announcement or on others' replies.



[h3]Community Cup 2025[/h3]
We are back for yet another round of the Community Cup, hosted by Dankus. This year, the Teams are participating for a chance to win 5000 Euros! With Casters such as Dankus themselves, Mo and one of our own Community Ambassadors Fraser, the finals will be played June 7th at 17:00 CEST.

Make sure to catch all of the action over on Dankus's Channel, or the HOI Youtube Channel!