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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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Will the soviets be getting speeches too or was language an issue? And will the speeches have their own radio station so they're easy to toggle? And honestly if you want to add to the South African and American communist trees to speak bit more to topical issues, that would be awesome.
 
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Will the soviets be getting speeches too or was language an issue? And will the speeches have their own radio station so they're easy to toggle? And honestly if you want to add to the South African and American communist trees to speak bit more to topical issues, that would be awesome.

@Podcast did say that the Soviets will be included, since they are considered part of the Allies.
 
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a country has a window of vulnerability that its enemies can exploit and which the player has to survive. The Soviet Purge is a good example of this, where it could be balanced around the idea that Germany needs to attack before the purge debuff wears off if it wants to have any kind of chance.

Clever! ... and kudos to the team for including such a feature to spice up the game.

I had not appreciated that game mechanic.

Just goes to show, one learns something new every day.
 
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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.



##################################
# 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.

Cool news, maybe this will shift doctrine meta away slightly from Trade Interdiction but maybe I'm hoping too much given how strong low surface detection is.

I'm curious if you have considered reducing the cost of cruiser conversion carriers, especially if given minimal equipment in order to try to mimic the escort carriers utilized heavily during the war for commerce protection by bringing ASW planes into convoy escort forces?

Any chance medium batteries could receive a small cost reduction too to incentivise building heavy cruisers more as currently they are rather pricy when you could built a relatively cheap battlecruiser at only a few thousand more IC?

When you say "- increased research cost on torpedo module upgrades" does this include torpedo tube modules for surface ships or purely the passive upgrades to all torpedoes?

I assume the changes by how much costs will change aren't set in stone yet as no values have been given so I'll leave that for now.

Are there any plans to have a look at the preexisting ship templates and technologies at the start of the game and adress some inconsistencies there? We've had a fairly extensive thread in suggestions discussing odd choices in these templates and how they could be corrected so rather curious if there is any work planned on that?

Either way, cool to see some changes, looking forward to more details.
 
It will also be interesting to see which countries are updated with the Soviets, you can argue Poland, Finland, Estonia, Latvia, Lithuania, Mongolia and Turkey
Finland is a given I‘d say. It claims to be a scandinavian / nordic country but in the HoI period it was tied into the Soviet war

but you missed the most important country.
HoIs Ulm. Tannu Tuva. They went and changed their leader portraifrom generic to originsl.
 
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Allied Armor Pack
While cool and all, having, say, SPAA as a dominant battalion is pretty rare. I know that it is possible to swap displayed model manually, but maybe you'll come up with something that would show most of those models in game without manual adjustments made by the player? Feels kind of a waste otherwise.

Speaking of: why not make more air models? At least, those are bound to be seen.
 
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I did it in HOI3, but it never felt right to give such strong bonuses out of nowhere which is why we avoided them for HOI4. I like the idea of comeback mechanics but I prefer them to tie into something real. As an example: rather than boosting the soviet counter attack you can penalize attackers through weather or the like in a non-linear manner

The mods "Hearts of Oak" and "Total War" have awesome campaign decisions. Germany gets temporary summer campaign bonuses and the Soviets winter offensives.

It works extremely well with the a.i., provides a historical immersion and is a pivotal strategic decision. It keeps you from constant attacks and rather awards careful planning for the perfect moment to launch the great offensive.

As Germany you constantly have this fear to go one bridge too far. It can be devastating to be on the attack when the Soviets launch their winter offensive.

So it's a key decision when to stop and dig in for the winter.

You guys should definitely look at the major mods. Lots of great ideas there.
 
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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:

You need to tone down the music, you can barely understand Sir Winston.
 
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The mods "Hearts of Oak" and "Total War" have awesome campaign decisions. Germany gets temporary summer campaign bonuses and the Soviets winter offensives.

The HOI4 teams approach is that you need to work for your bonuses. Like with decryption - you can get very powerful bonuses, but you have to invest and do the work to unlock the bonuses. I believe the team would rather develop the logistics system to allow us to build stockpiles of supplies and equipment prior to major offensives, and then we can get a bonus. More immersive than a decision button.
 
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I absolutely loved hearing the speech and where you are going with the atmosphere, but you know, I felt like sometimes in those 6 minutes the music could have been a bit quieter because it simply drowns out the speech vs accentuating it, and it's not like it was particularly set to the rhythm of the Great Orator's speech either.

^Just a bit of a picky comment in an otherwise fantastic effort, but still wanted to share my 2 cents :) it's not a deal breaker
 
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I'd be really interested in some Alt-History speeches... I'd like to hear some newly instated Kaiser thanking his loyal followers 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 <.<
 
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I'm very excited for what's next for hoi4, it's by far my favorite pdx game and one of my favorite ww2 games.

Glad that the next expansion is almost surely the soviets (hopefully with poland and Finland too), the eastern front by far needs the most work now, and hopefully after you guys rework all the majors, you can move on to smaller theaters and features. I'm also glad you guys want to shorten the lengths of time between content drops too.

I hope Barbarossa majorly rebalances land warfare; Germany is nigh unstoppable and land war in general is almost entirely death stacks that result in ww1 style combat, when it should be fast and mechanized.

Either way thanks for all the hard work!
 
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Imagine the forum drama if we started every other dev diary with "Oh by the way, the thing we told you about last week that all of you got very hyped about?
Imagine if the dev diaries wouldn't actively fuel the hype:
We have some massively awesome stuff planned and I think you are all gonna like it
1.11 Barbarossa
Well, well, well, what do we have here?

and instead describe things that were happening during development regardless of whether they end up in the game or some payed DLC.

Yeah we're not doing that anymore.
If you provide a (valid) reason why it got scrapped, I don't expect a lot of people causing drama.
 
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Would it be possible to give medium batteries a lower target signature than battleship guns? It still feels like cruiser heavy guns are only useful for getting the hull classed as a CA and maybe threatening convoys.
 
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I think an opposite approach can work, where a country has a window of vulnerability that its enemies can exploit and which the player has to survive. The Soviet Purge is a good example of this, where it could be balanced around the idea that Germany needs to attack before the purge debuff wears off if it wants to have any kind of chance.

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?
 
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I'll be honest with you. Hearing the example track you gave in the post made me want to definitely not buy this pack. The speeches seem to be more distracting and frankly annoying to listen to. Mainly because of the quality. Now, I understand that the original soundfiles of these speeches are low quality, but maybe they could be re-recorded by some sound-alikes?
 
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Would it be possible to give medium batteries a lower target signature than battleship guns? It still feels like cruiser heavy guns are only useful for getting the hull classed as a CA and maybe threatening convoys.
Absolutely agree, I think making heavy cruisers count as capital ships in the first place was a mistake. At best they served as flagships for smaller squadrons or navies when no true capital ships were available. However in reality their duties and roles were more or less identical to that of a light cruiser, just with marginally more firepower (until later new light cruisers like the Brooklyns, pre-refit Mogamis etc. had similar or superior firepower.)
 
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