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HOI4 Dev Diary - 4th Anniversary

Hi everyone! This week is Hearts of Iron IVs 4th anniversary. I’ve got some cool data to share with you, new armor and radio packs as well as patch for you to celebrate! All of this releases tomorrow :)

A Look Back & Cool Numbers
It's crazy how Hearts of Iron keeps growing. I personally started with playing HOI2, and worked on HOI3 as a coder and game director on HOI4, and while people still call it a niche experience for WW2 buffs, it has also grown to be so much more (or us WW2 nerds are more numerous than we think :D). Around La Résistance release we clocked a new record on monthly players of 899k (the 1000 of you that didn't log in that month are responsible for my OCD flaring up!). HOI4 is quite unique in how stable the growth is. Most games that aren't multiplayer or the like usually has big dips between releases. I think the two big factors that keeps us so stable is the replayability as well as the amazing mods that keep updating giving people new stuff to play with continuously :) Here is what the curve has looked like over the years:
1591171103323.png


I also took a look at country popularity between the last year and the release year. These are the top 10 nations currently with comparison to 2016:
1591110039964.png

Most see relative reductions here because we have in general made a lot more nations playable with more focus trees and other improvements (in 2016 Poland had Hungary's spot while now its pushed below both Spain and Hungary). There are a couple of obvious increases who all seem to come from focus tree changes also :)



Allied Armor Pack
Tomorrow we also release the followup to last years Axis Armor Pack, this time for the allies. This includes 45 armored vehicles for USA, UK, France and Soviets. On top of this we also add in 32 tanks from the Colonel Edition for those nations also for a total of 77 :) This is one of the reasons that we stopped selling the Colonel Edition last month - it was making it messy to buy cosmetic packs and we didn't want to split stuff up further. To make sure previous colonel edition players don't feel like they get as much, and also because its been such a great year for HOI4, we will be giving the whole pack for free to all those who had the Field Marshal. or Colonel Editions Enjoy!
(the observant players may remember that there is some ships in the colonel edition also, people who have that will keep them but they are not included in this armor pack. We will sort those boat boys out in the future).

Below are some examples of vehicles included:
allied_armor.png


Allied Speeches
People seemed to like the radio addition last year, but this year we wanted to test something a bit different and more tied to gameplay. We have added 70 minutes of speeches from allied leaders and commanders, set them to music and trigger them based on ingame events. So for example when Japan declares war on USA you will be able to hear Roosevelt deliver his "a date which will live in infamy" speech.
Here is a sample using one of Churchill's more famous speeches to give you an feeling for how it will sound:

Its a great feeling when they kick in and adds some really nice historical flavor :) Note also that they are playable like any other tracks should you want to.

1.9.3 Patch
For this patch we wanted to focus on naval issues and improvements as we didn't touch that very much for La Résistance. To summarize the most important changes:

Naval tech rebalance
It's best to check the changelog for details here, but our goal has been to make tech investments into more efficient submarines more expensive and sub countering and investments into capital ships cheaper.

Convoys and stun-locking
A very annoying strategy in multiple and sometimes in SP has been being able to essentially stun lock an enemies transports of troops in place at sea by lots of small naval engagements with submarines. Even if well screened they still need to wait to retreat and then would get caught again and again, sometimes taking months to get across the atlantic. To deal with this we have increased the retreat speed bonuses from being well screened and also implemented a cooldown system. This system will give transports a cooldown after being caught where they can not be re-spotted again. The length of it depends on the length of their path as well as how well screened they are. For an unscreened vessel they will be caught pretty quickly in more interceptions while a properly screened one can continue on until the invasion beach if its not too far.

Carriers and other naval changes
Carriers in the pacific really struggle with the large air zones and the weather penalties. It didn't make sense to us to apply the area size penalties to a mobile base with so few planes, so now any mission targeting a specific location (port strike, CAS etc) for planes stationed on a carrier will not have this penalty.

On top of this it didn't make sense to have carriers planes suffer a 100% penalty from bad weather when land based ones had a much smaller one. While I doubt any planes could take off during a really bad storm, it makes little sense when we only really have one level of weather here to make it so brutal, so this penalty has been reduced to 80%. We also felt that if the weather is truly this bad guns really should be struggling more than they do as well as doubled that penalty to 20% to close the gap.

Carriers now also help the fleet overall. The side with the carrier plane advantage in the battle will penalize positioning of the other side, similar a bit in spirit to the effects of air superiority on land. We also made light guns a bit worse and buffed targeting and power of bigger guns to try and strengthen mixed fleets. We have also increased the base detection abilities of carriers a bit to better model how important they were for spotting enemies at sea.

Another thing of note is that we have fixed an annoying interaction between air superiority and naval spotting. Because air superiority applies on average on the zones a task force was operating you could shield them with planes in a zone they were not even in, which might be somewhere your enemy couldn't even reach and contest. Now it will be looking at the specific area they are in instead.

Out Of Syncs
Telemetry was telling us that the vast majority of out of syncs were happening in the first half of 1936, and for weeks we simply could not reproduce this inhouse, but recently we had a breakthrough. We found some data related to technologies that was not properly reset when entering a new game and this is hopefully the core reason for this. We will be looking at telemetry data to hopefully see the OOS frequency take a nose dive, because this stuff is truly hard for us to test fully ourselves, but we are optimistic!

Expand here to see the full patch log:
################################################################
######## Hotfix 1.9.3 "Husky" ########
################################################################

##################################
# Balance
##################################
- decreased suppression value of SP-Art battalions
- decreased suppression value of SP-AA battalions
- decreased suppression value of SP-AT battalions
- decreased research cost on destroyer hulls
- decreased research cost on depth charge technologies
- increased research cost on 1940 and 1944 submarine hulls
- increased research cost on torpedo module upgrades
- decreased research cost of naval munitions upgrades for light and heavy guns
- decreased research cost of armor schemes
- increased the cost of initial radar tech, lowered cost on all other radar techs
- decreased IC cost of all ship heavy batteries
- increased damage of all heavy ship batteries
- increased piercing of all medium ship batteries
- increased damage of all medium ship batteries
- Carrier planes no longer take area coverage penalties on their targeted/ground missions
- Increased carrier hull surface detection base from 20 to 26
- Added a cooldown timer after naval transfers are engaged at sea and escape to avoid stun-locking issues with many small fleets. The cooldown depends on the screening efficiency of the defenders so a defended convoy will have a longer cooldown the better defended it is
- Added an extra speed boost to convoys retreat speed when screened
- Effective carrier plane advantage in naval combat now gives penalties to positioning for the other side
- Increased air-to-air damage factor in carrier battles from 5 to 6
- increase air attack targeting scoring for carriers to make them more likely targets for other carriers
- increased naval hit penalty from 10% to 20% in heavy rain
- reduced carrier traffic penalty from 100% to 80% in heavy rain
- Reduce heavy gun target signature from 90 to 80 and increased light gun target signature from 40 to 45 to make heavy guns a bit more versatile and light guns a bit slower at picking off screens
- Patrol convoy raiding and convoy escort missions now rely on local navy position for air superiority rather than average of air zones to stop high air superiority in a zone from saving the ships from spotting in another.


##################################
# Stability & Performance
##################################
- Fixed OOS related to asking an operative to resume their mission after the operation they are assigned to completes
- Fixed OOS linked to technologies not being properly reset between games
- Fixed OOS triggered by a country asking for manpower after a civil war
- Prevented crash when trying to respond to faction invite from a faction that no longer exists
- fixed a ctd that happens when a non-existing capitulated country checks for uncapitulation


##################################
# Modding
##################################
- Added play_song and scoped_play_song effects
- added on_war_relation_added on action (scope is attacker, from is defender)
- Made targeting weights for air-to-ship in naval combat moddable. See NAVAL_COMBAT_AIR_*_TARGET_SCORE defines.


##################################
# Bugfix
##################################
- Updated the forum link in main menu to match the new forum
- Bulgaria will no longer start with Flexible Navy focus completed in 1939

So what are we up to now?
We have been wanting to shorten the time between content update for a while and are going to take a serious stab at it now. That means that we are currently working on two things at once in parallel actually. In the pipe we have 1.10 ‘Collie as well as 1.11 Barbarossa. That's about as much information as I can give you right now. We are not yet ready to start dev diaries on ‘Collie’ but look forward to it some time after summer vacation. We have some massively awesome stuff planned and I think you are all gonna like it (if people wanna see the roadmap, it was last updated in this dev diary).

As part of the anniversary we are also doing a really cool new take on the 3-day war stream with influencers vs devs and... democracy?
1591131033902.png
Check out details here!


aaaand thats it from me! Hope you will like the updates and everything else tomorrow!
 
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Lets hope this awesome speech was picked for the Soviets.

Just wanna give you some trivia if you are (or anyone else is) in the mood for it.


This guy is the "Voice of the USSR". If you're listening to Soviet radio or propaganda, chances are you're listening to him. Stalin himself was a Georgian national, and that means his accent was fairly distinctive. When you hear him talking about the "Russian nation", it sounds a bit... like if you had the US president speak with a distinctive French or Spanish accent on air.

/Edit: I'm not sure so feel free to doublecheck this, but there's some rumor/trivia going around in Russia that the Germans were so keen on capturing him to deprive the Soviet people of a well-recognized voice, that there were some cat-and-mouse games (relocating Levitan, false broadcasts at diff locations, etc) during the siege of Leningrad / or when Germans were advancing to Leningrad. But like, that's totally far-fetched and I'm just trying to recollect the tales I heard when growing up there.
 
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So it costs more to research a 1940/44 sub than a carrier??? But then it costs the same to research a carrier and a destroyer...

All-in-all, a good Hotfix.
 
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or even a news report regarding the crashing of Hindenburg as another way to take this all just a faint reading of the current news headlines would be really interesting and immersive for me.

Sale tomorrow to celebrate. may be missing a DLC <.<

*Edit I just learned that @Mescaline has already made a link to the same thing I quoted, so the idea is his. I wholeheartedly agree.

I really like the idea of news reports from the radio. The Soviet Union had this man:

"Handpicked by Joseph Stalin, Yuri Levitan is still revered as the voice of World War II. It is 99 years this month since the so-called “Voice of the War,” Yuri Levitan, was born. Blessed with a naturally powerful and commanding voice, he unified the huge Soviet Union in the face of the Nazi threat."

I am sure the British had a similar voice, and there are probably other voices for the other countries. It would add to the atmosphere of the game to have the option to hear such newscasts, or something similar that works for the game.
 
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I really like the idea of news reports from the radio. The Soviet Union had this man:

"Handpicked by Joseph Stalin, Yuri Levitan is still revered as the voice of World War II. It is 99 years this month since the so-called “Voice of the War,” Yuri Levitan, was born. Blessed with a naturally powerful and commanding voice, he unified the huge Soviet Union in the face of the Nazi threat."

I am sure the British had a similar voice, and there are probably other voices for the other countries. It would add to the atmosphere of the game to have the option to hear such newscasts, or something similar that works for the game.

Yup, I've linked his wiki above btw. I think there's some room to employ diff voice packs, though it might be a bit tough to deal with copyright in some cases.
 
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My issue with that approach is that it has proven very tricky to balance in an interesting and historical way both in single and multiplayer in mods.

If this "purge debuff" is connected to a NF ( which is the most common way to do it in mods at least ) then you can bet that every Soviet player that has basic knowledge of how this works is going to Purge Jan 1936 or as damn soon as it's possible to do so if that can shave a year or two of the debuff ( which is massive ), and in case of a Historical AI 1941 invasion you might even fight it without debuff or with a very low one.

At the same time this also greatly switches your German player strategy to be to attack Soviet as soon as possible, possibly even before France, if attacking Soviet in 1939 means the Soviets will have a penalty much larger and longer duration vs a historical date of attack. Even more so if the Soviet AI is punished by being scripted to do a more historical 1937-38 Purge while a much earlier one is possible to do.


I think a shorter unavoidable penalty upon war with a major power is a much better way to model the historical issues with the disorganized and "shocked" Soviet Army. This penalty could then be scaled dynamically to go away after either a set time or after Soviet losses / Axis progress have reached certain levels where it can be deemed the Soviet Army has had their "baptism by fire" and can start to fight back ( historically this would be mostly or fully gone around the battle of Moscow ).

Some parts of it could still be connected to the NF tree so that you feel what your doing as Soviet is reorganizing the army but I think indirect/long term things like speeded up doctrine research ( vs a very low peacetime penalty baseline ) or bringing back / unlocking key Generals or Ministers that can assist the Army/Airforce preparations would be much better suited for NFs. Because the alternative is to have the main path of a massive disorganization combat penalty from Purges -> Full recovery in NFs that can, will and must be rushed forcing a single and obvious NF path to be repeated for any Soviet player in a historical factions game.



I guess what I am trying to get at is that historically it's only 6 months from DoW in 1941 ( where the penalty should be very severe ) until gates of Moscow ( where the penalty should be almost gone so Soviet can make a historical successful winter counterattack ). If that is controlled by what NF order Soviet picks back in 1937 it could very easily be overly punishing towards a new player that Purges say 6 months late or easily avoidable by a knowledgeable one that Purges ASAP. And how can it possibly handle a 12 or 24 month early Barbarossa in 1939/40?

Good job pointing out some of the disadvantages of a single, or overpowering pre-war debuff and how it might force players down a predictable path to undo the debuff before the war starts. This is not optimal, as the decisions before the war is where a lot of fun is had. Making the path predetermined, turns 1936 to 1940 a simple fast forward exercise.

Instead of relying on such a debuff, maybe the Russian military could have an equipment disadvantage in its combat battalions that lasts until a specific time the developers see as appropriate to simulate those first months of fighting.

Why equipment? Well equipment is not just the tank or artillery piece. It is an abstraction of the tank, its spare parts, ammunition, and other costs to the nation to keep that one tank in the fight. In this abstraction, the Russian's national cost to keep that tank or artillery piece in the fight is much higher due to the Purge creating inefficiencies into the system. Many of these inefficiencies do not become self-evident until the war begins.

So before the war begins, making equipment needs for Russian battalions much higher than other major powers could reflect this national problem. Instead of an infantry battalion requiring 1000 infantry kits, it might require 1500, or whatever the developers discover is appropriate to reflect the unique national cost Russia had at the time. It could be realistic as the Russians had so much equipment in the beginning, only to loss much of it in the very first months with little effect on the enemy.

As the Russian military fights, its discovers the inefficiencies in its system and can use army xp to start reducing it through decisions. It could be a gradual increase in efficiency that could eventually make Russian battalions require the same number of equipment as other major powers. As the inefficiency is reduced the now excess equipment in the existing divisions would return to the stockpile to be more efficiently used as replacements or new divisions.
 
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Good job pointing out some of the disadvantages of a single, or overpowering pre-war debuff and how it might force players down a predictable path to undo the debuff before the war starts. This is not optimal, as the decisions before the war is where a lot of fun is had. Making the path predetermined, turns 1936 to 1940 a simple fast forward exercise.

Instead of relying on such a debuff, maybe the Russian military could have an equipment disadvantage in its combat battalions that lasts until a specific time the developers see as appropriate to simulate those first months of fighting.

Why equipment? Well equipment is not just the tank or artillery piece. It is an abstraction of the tank, its spare parts, ammunition, and other costs to the nation to keep that one tank in the fight. In this abstraction, the Russian's national cost to keep that tank or artillery piece in the fight is much higher due to the Purge creating inefficiencies into the system. Many of these inefficiencies do not become self-evident until the war begins.

So before the war begins, making equipment needs for Russian battalions much higher than other major powers could reflect this national problem. Instead of an infantry battalion requiring 1000 infantry kits, it might require 1500, or whatever the developers discover is appropriate to reflect the unique national cost Russia had at the time. It could be realistic as the Russians had so much equipment in the beginning, only to loss much of it in the very first months with little effect on the enemy.

As the Russian military fights, its discovers the inefficiencies in its system and can use army xp to start reducing it through decisions. It could be a gradual increase in efficiency that could eventually make Russian battalions require the same number of equipment as other major powers. As the inefficiency is reduced the now excess equipment in the existing divisions would return to the stockpile to be more efficiently used as replacements or new divisions.

I agree with you in general, but wanna point out your last paragraphs in particular.

I think a gradual or scaling system like the one we can see in the Sino-Japanese war on both sides could be beneficial here. Same as the Japanese have to deal with "war commitment" debuffs or China has to root out its corruption, the Soviets should be able to gradually refill its CO ranks. What I want to see though and what I want to ask (or even beg for) in advance is make it an interactive system that is based on how you perform. If the SOV player manages to deal a certain amount of casualties, or hold the certain points by a certain time, or meet some other prerequisites, they should be able to get corresponding buffs to their generals or something of the like.

Please, invest into the events that make the Soviet Union feel like one. I can't say I have an exact idea as to which mechanic to "tie" it to precisely, but the general idea is that the game should go with what you're doing, not with RNG. And I'd for one love to create, drill and improve my generals (as I would love for that rework to be the very foundation of a new system for advancing your generals through ranks and skills and so on).

Because grinding FM in Spain/Ethiopia/etc is just dull.
 
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Very excited about the carrier buffs. The positioning buff sounds kind of like the old "combined arms" bonus from HOI3.
1) Would it be possible to grant a small "combined arms" buff to carrier planes if all three types are present in the battle? This would further incentivize the use of historical CAGs with fighters, dive bombers, and torpedo bombers.
2) Would it be possible to lower the screen requirement for heavy cruisers? Historically there was little difference in the use of heavy/light cruisers except as flagships for task forces and fleets.
 
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I am sure the British had a similar voice, and there are probably other voices for the other countries.
For the US it was definitely Roosevelt himself, with his "Fireside Chats" broadcasting directly to the people.

I am also still hoping for De Gaulle speeches...
 
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I agree with you in general, but wanna point out your last paragraphs in particular.

I think a gradual or scaling system like the one we can see in the Sino-Japanese war on both sides could be beneficial here. Same as the Japanese have to deal with "war commitment" debuffs or China has to root out its corruption, the Soviets should be able to gradually refill its CO ranks. What I want to see though and what I want to ask (or even beg for) in advance is make it an interactive system that is based on how you perform. If the SOV player manages to deal a certain amount of casualties, or hold the certain points by a certain time, or meet some other prerequisites, they should be able to get corresponding buffs to their generals or something of the like.

Please, invest into the events that make the Soviet Union feel like one. I can't say I have an exact idea as to which mechanic to "tie" it to precisely, but the general idea is that the game should go with what you're doing, not with RNG. And I'd for one love to create, drill and improve my generals (as I would love for that rework to be the very foundation of a new system for advancing your generals through ranks and skills and so on).

Because grinding FM in Spain/Ethiopia/etc is just dull.

I do like the idea of having player actions inside the game remove the Soviet debuff instead of using almost mandatory Focus or Decisions to remove it.
 
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*Edit I just learned that @Mescaline has already made a link to the same thing I quoted, so the idea is his. I wholeheartedly agree.

I really like the idea of news reports from the radio. The Soviet Union had this man:

"Handpicked by Joseph Stalin, Yuri Levitan is still revered as the voice of World War II. It is 99 years this month since the so-called “Voice of the War,” Yuri Levitan, was born. Blessed with a naturally powerful and commanding voice, he unified the huge Soviet Union in the face of the Nazi threat."

I am sure the British had a similar voice, and there are probably other voices for the other countries. It would add to the atmosphere of the game to have the option to hear such newscasts, or something similar that works for the game.

They kind of do similar with Stellaris advisor voices so (Well i feel the technical aspect must be similar since its just a prerecorded clip playing with a trigger...). Would be great to hear a patriotic accented voice in a newsreel style in the background for each nation. Might be difficult to get every nation but would be great future flavour for DLCs to with a focus tree get a voice that reads some of the news articles.
 
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Hooray for speeches.
 
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With the Colonel Edition you got new Tank and Ships models.
The Colonel Edition isn't sold anymore, and the Tanks got transfered in the Allied Tank Pack, but the Ships aren't transfered into anything. So right now you can buy those Shipmodels/2D Art anymore which shall be changed in the future.
I bought the Allied Tank Pack but I didn't receive the tank models from the Colonel Edition, just the new models!
 
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For this patch we wanted to focus on naval issues and improvements as we didn't touch that very much for La Résistance. To summarize the most important changes:

Naval tech rebalance
...

Convoys and stun-locking
...

Carriers and other naval changes


Maybe you don't consider it one of the most important changes, but I sure do, so, uh. Are we finally going to be able to drap and drop squadrons and fleets to reorder them in the UI? And likewise for spies, while we're at it? I don't understand for the life of me why, after solving this problem so neatly with armies, you reintroduced it for two other theaters of war.

Also, imo the music over the speeches is a bit too loud, I would rebalance it a little. It's actually hard to hear the words in some parts, for me.
 
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