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HOI4 Dev Diary - Combat and Stats changes

Hi everyone and welcome back to another dev diary! Today is about various changes that affect combat and units. With the Barbarossa update we want to shake up the meta a bit and also change a few stats and other aspects to make using the tank designer more interesting and rewarding.

High Command bonus changes
For a long time now unit bonuses from high command have confused people. Most expect that they apply to battalions, when in fact they apply only if their target unit type was “the majority type”, which was basically a weighted type count. They also could overlap, so infantry, mountaineers and artillery would apply to the same units letting you stack stuff in ways that was never intended and quite unintuitive.

Screenshot_1.png


This system has now changed, and divisions get bonuses based on their composition, this is a straight up ratio based on the number of non-support battalions of each type, so a 2x artillery 3x infantry division will be 40% artillery 60% infantry.
Battalions are always classified as a single type for this (even though some are scripted with multiple types) based on this priority:
cavalry > armor > artillery > motorized > mechanized > infantry

The exceptions being rocket & special forces, which both act as an addition, so if the 3 infantry divisions in the example above were mountain units, then the division would also be 60% special forces and if the 2 artillery are nebelwerfers it'd also be 40% rocket

When counting the battalions of armies (ie when we have an actual unit and not only a division template), battalions that lack equipment will count as less, so a Light Tank battalion with only half it's tanks will count as 0.5 battalions (and not count at all if without tanks). The total sum of the compositions will still end up 100% (unless every battalion is without equipment).

Screenshot_3.png


To make it easier to see this we now have an indicator in the division windows showing the breakdown.

Combat Width
As a part of our efforts to shake up the 40/20 width meta, we have made changes to the combat width of province terrain. Province widths now range from 75 to 96. Plains have a new base combat width of 90, while Mountains have a new combat width of 75. Most of these widths will not divide into each other easily, hopefully moving the ideal width away from multiples of 10.

Urban provinces are now the “widest” with a width of 96. But this does not mean they will be the easiest provinces to overwhelm. Mountains, marshes, and urban provinces now have reinforcement widths of ⅓ of province width instead of ½. This should hopefully give these provinces a slight defensive buff, while allowing us to open up pushing power in the more open tiles.


Screenshot_2.png


In conjunction with these changes, we have also been looking at reducing the overstacking penalty. We hope that this will alleviate some of the need to have divisions that are the perfect width for a given province. But at the same time, smaller countries should now be able to specialize their division width to suit their home terrain more appropriately.

Breakdown (numbers not final etc etc)
  • Plains
    • Standard 90
    • Reinforce 45
  • Desert
    • Standard 90
    • Reinforce 45
  • Forest
    • Standard 84
    • Reinforce 42
  • Jungle
    • Standard 84
    • Reinforce 42
  • Hills
    • Standard 80
    • Reinforce 40
  • Marsh
    • Standard 78
    • Reinforce 26
  • Urban
    • Standard 96
    • Reinforce.32
  • Mountain
    • Standard 75
    • Reinforce 25
One of the major things that make larger divisions like 40 width armor hit disproportionally harder than smaller ones is also how targeting and damage works inside combat in relation to the enemies defense. Essentially the larger divisions make more efficient use of concentrated damage as it punches through defense. To solve this we are doing a few things. First of all we are weighting the targeting towards wider divisions being more likely targets and also when picking targets to try and match it to have wider divisions spread damage over smaller rather than always concentrating it. They will probably still hit harder, but combined with width changes and other downsides of larger divisions it should make it less clear cut.
However, this part isn’t quite done yet though so I’ll cover it again in more detail in one of the “bag of tricks” diaries in the future when i see how it pans out, but I figured it needed to be mentioned now ;) That said though, to wet your appetites here is a little tease from a debug mapmode in development...
1620214309589.png


Armor and Piercing
Currently the effects of having stronger armor than the enemy can pierce, or being able to pierce an enemies armor are binary and give fixed bonuses. This meant that there wasn't really any benefit to have more armor than you needed to stop the enemies piercing, and also that being a single point of piercing under enemy armor was just as bad as having no piercing. So things were quite binary. With the tank designer coming we wanted to make it feel like your investments in upgrades were always worth it, so we are changing armor and piercing to have more gradual effects.

Armor > Piercing
  • Unit takes half damage (as it currently works)
Armor < Piercing and Amor > 0.75 * Piercing
  • Take damage between half damage to normal damage by difference in value
Armor < 0.75 * Piercing
  • The unit takes normal damage
Lets break this down with an example:
  • A panzer division has an armor value of 52
  • Its being attacked by an infantry division with some anti-tank guns. Their piercing is 60
  • If this was the old system this armor would be worthless and not reduce damage at all
  • Now because its close enough (between 60 and 45), so you get roughly half of the normal effect around 25% reduction of damage.

Reliability
For the tank designer it was important that reliability was more impactful if it was to be a good tradeoff with other aspects of design, so we needed to change it up (lest @CraniumMuppets 0% reliability tank monsters would take over the world). Now it will not just affect rate of loss in attrition but various other aspects:
  • Reliability affects losses from attrition like before
  • Reliability now affects org regain when moving, and also makes any weather related org effects more impactful when low
  • Lower reliability scales up all impacts from weather so if facing extreme weather a unit with low reliability equipment will suffer more of those weather effects
  • At the end of combat units with better reliability will be able to get back a certain amount of tanks etc to simulate that simple more reliable constructions would work better for battlefield repair and be less fragile when taking damage. So it's a bit like capturing enemy equipment in combat - but in reverse :cool:

Screenshot_4.png


Our goal is that this creates interesting tradeoffs when designing equipment and will make you have to consider if its worth switching a strategy focused on speed and firepower towards reliability when operating in bad weather and tough areas like the Russian winter or in northern africa or jungles.

Oh, and I figured now might be a good time to point out that there will be a future diary on weather changes and other cool related stuff, so these changes aren't completely in isolation. But one step at a time :)

But before we go, a few words about the studio...

Studio Gold
Hello everyone, my name is Thomas, but perhaps better known as @Besuchov here :)

As you saw here we have recently reorganized ourselves a little, moving from a big centralized Stockholm studio to splitting ourselves into Red, Green and Gold. This is mainly an internal org shift to make sure we keep our growing organization firmly focused around making good games. You shouldn't notice too many differences in the short term, we are still PDS making GSG on the Clausewitz engine, but it does mean that we can align each studio to the particular games. Since you will hear the studio names every once in a while, I just wanted to say who I am and what the studio is responsible for.

My role is Studio Manager, which means I'm accountable for the long term success of Studio Gold and working with things like management, staffing, and long term plans. Studio Gold has as its main focus Hearts of Iron (but we may or may not have some secret other stuff as well). Directly making the games though, that's still the job of Podcat and the team, but I intend to do my best to create an environment where we have the best chances to make great games together.

For me this is coming full circle at Paradox. I started as a programmer in 2004 and one of my first tasks was to work on Hearts of Iron 2. Since then I've done various things including being lead programmer for Hearts of Iron 3 (and Victoria 2), Project Lead for EU4 and more recently Studio Manager for PDS. Next to EU, HOI is my favorite game and I'm delighted to be back in a place where I can focus on fewer games and where that game is Hearts of Iron. You will see more of me in the future even though I will mostly take a backseat to the team working on the game.

That’s all, see you all again next week for more dev diary goodness!
 
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@podcat , With the new work on reliability, will we see the ability to create variants of equipment we could not before like trucks and infantry equipment. Just the 4 attributes box that includes reliability as one of the 4?
I'm also curious about this. As well as if the maintenance company will provide further bonuses to the trickle back effect of higher reliability.
 
Something I want to comment on is that the division designer's handling of combat width has been one of the weakest and most glaring problems of HOI4, and I'm a bit worried in advance that this land-combat content update might turn out to be a missed opportunity on a lot of things. While the 40-width meta is indeed an issue, its not the only issue with the system

  • Too small a combat width is a big problem. If you've ever seen people spam 2-width divisions in-game, its an unbreakable wall against things that aren't 40-width artillery or tank spam so long as manpower reserves holdout. The problem is that just a single battalion of infantry has 60 org (much more with doctrines). What makes things worse is that units have org regardless of whether they have equipment or not. When you spam out tons of cheap units and have a high-reinforcement rate, you get an "Enemy at the Gates" scenario whereby hordes of cheap infantry with almost no weapons can literally hold off enemy offensives by blocking the roads with their piles of dead bodies. You have to meet a certain threshold of soft attack such that it can shatter each unit immediately and the need for such things also reinforces the high-width combat meta.

  • There is also a historical aspect of how divisions were organized. Generally triangular divisions were used because they had a system of placing two brigades at the frontline and rotating 1 brigade in reserve. In addition to providing rest, this reserve element could respond to threats or opportunities as the situation required. Generally most armies followed this blueprint with varying levels of fire support attached. The pentomic divisions that everyone builds currently are really only seen as the cold war heated up. The idea behind Pentomic divisions and integrated combat units was to reduce the time required to initiate an attack to the bare minimum. This was achieved by minimizing the communications overhead to coordinate with various inner-army branches. By being to able to launch a full force assault as quickly as possible, the window of time that the enemy had to respond with a nuclear strike would be minimized. Right now the game doesn't encourage the player to follow historical trends in any way shape or form.

  • Smaller units punching a lot less also has big issues. Mainly in that when fighting at a disadvantage, one cannot implement a strategy of defeat in detail with smaller more flexible units. A big trend among a lot of militaries was to have their elite and mobile units be put into independent brigades or smaller divisions. In vanilla HOI4, doing this would be absolute madness as you want your most expensive assets to take the least amount of casualties due to how damage & soft attack stacking vs defensiveness works. As a very simplified example, imagine that a ton of infantry divisions on the frontlines are dueling in 1v1 matches. The idea behind a small elite rapid reaction force is to be able to move quickly from combat zone to combat zone to give a numerical advantage quickly in many simultaneously combats back-to-back. Then leveraging Lanchester's Law which says that combat strength of a force is the square of its numbers, you can turn each 1v1 duel into a decisive victory in many places as this elite unit moves from 1 place to the other. With independent brigades, you can do this in multiple places at once constantly. But its very undesirable in HOI4 because wars tends to always end up as western-front WW1 style conflicts of attrition and high-width units with very expensive stuff must take as few casualties as possible. One of the first things everyone does upon loading the game is deleting those 8 width motorized divisions, 8 width cavalry units, or 8-width tanks units--much to my dismay.

  • There is also a lot to grumble about with artillery having 3-combat width and all. Personally, I think its a huge culprit in letting people fill up the combat width too easily. The easier it is to max out combat width, the easier it is to get WW1-style western front stalemates. (note, the western front had several factors, not just a "lack of tanks" that resulted in it being such a static meatgrinder. Many other places during WW1 were certainly not static despite the level of technology and equipment available then). I could write pages and pages ranting about artillery being unrealistic in so many ways as its portrayed in HOI4 currently, but that's probably its own post. But as a quick summary, the biggest thing about it that dismays me is that very simplistic implementation of artillery in HOI4 robs a lot of the nuance of the quality and capability of certain armies. There was a huge gap between the heavy-weapons capability of the Polish and the Chinese army for example, but they both just have "basic vanilla" infantry units currently. You can't overcome certain fortifications without some pretty big dakka (210-320mm stuff), you can't effectively win fire-superiority overtime against another well-equipped enemy without some very long range howitzers, you need lots of cheaper medium howitzers if you want lay down huge volumes of pre-assault barrages, and you need lighter artillery guns to deal with smaller emplacements that require direct-fire precision on the frontlines to eliminate, just to name several examples.
    4aRl8IX.png
<LINK> A thing to point out, was that just simply motorizing some of the bigger pieces shown above was a huge technical challenge in and of itself that not all interwar armies had the capability of doing. <LINK>

---------------

My 2-cents is that land combat in HOI4 needs more than just a few small tweaks. I'm worried we're going to be stuck with the same-old, same-old meta (just slightly less acute in being more powerful) and the same old problems in historical representation and balance (just slightly less problematic). I'd urge you folks to be much more experimental if anything to try and learn lessons for building a foundation for Hoi5 that will inevitably happen someday.
Amazing post. While i disagree on needing to have different pieces of artillery because it just would bloat the already clunky UI, I definitely agree about the Pentomic Division structure HoI4 suffers from (and it does make me miss the simplicity of HoI3 with the Brigade system. Most divisions just had 4-5 Brigades) and how Elite Units in HoI4 are discouraged because the smaller the division is, the more damage they take, and the thing you least want is taking casualties with Elite divisions.

Would love to see Elite units not just be these individual huge width divisions and instead be more like a mobile unit being moved around the front to contain a breach or make that extra thrust to breakthrough the line
 
Will you scale the High Command bonuses after depending on type? Most divisions won't have much line artillery, so a bonus to just one or two BNs won't matter much compared to a bonus for infantry.

And how about support artillery? Will they benefit from an artillery bonus?
support doesnt add to it, but would technically benefit if there is line infantry. As for balancing a lot of these didnt kick in at all before so we'll likely need to do some balancing on a few of them

I love these changes, but I disagree with some of the width choices, I feel like jungles should have a smaller width since they are so dense and very difficult to maneuver through. I would almost argue that they should be smaller than mountains, but I also feel mountains should be broken up into forested and rocky mountains since that has a huge impact on what sort of maneuver corridors are available to a military force. I like the idea behind smaller reinforcement rates for these areas as well.
Dont forget that there are other factors like combat modifiers also at play. where jungles are super horrible to operate in as is (especially with the new supply flow.)
 
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You can buy generals with PP. For some countries it is explicit simulation for lowering available PP.
AI currently fights mostly with 20w, new target goal looks will be around 20w - 30w
True but there's like, ~3 generated generals per country before it's just repeating the same portrait but with a different name.
 
Presumably it is 0:00 1.1.1936.
0:00 where?
It could be that it's already dawn in Finland but still night in Sweden.
Also, what I meant is that temperature is not always "normal" for example, as we speak, it's currently dusk in Kiev and it's 19C, its still noon in Rome and it's only 18C.

So looking at the temperature now would give the impression that Rome is colder than Kiev (and technically it is at the moment), but as far as averages are concerned, Kiev is quite colder.

I can post temperature data as well.
No need friend, i know Finland has slightly overall lower winter averages than Sweden, my point was that the map you posted doesn't quite prove your point, but you are still correct in your claim nevertheless.
 
The High Command bonus changes are good.

The armor and piercing changes are good.

The reliability changes are fine I guess. Reliability was already a top-tier stat for SP land equipment.

However, I'm not a huge fan of the combat width changes. It's fine to change the 20/40w meta, but having different widths for every terrain type is a level of micromanagement that's unhealthy for the game. It doesn't sound like fun to have to shuffle units when fighting in plains, then shuffle in different widths when fighting in forest, then shuffle in different units *again* when fighting in hills. You say you're looking at reducing the overstacking penalty; perhaps the best way is to make it so that excess width never reduces overall combat stats, it just stops adding more, e.g. having 81w in a battle that was 80w would give you the effects of essentially having 80w, and the 1w that couldn't fit just wouldn't be used. I'm not sure what math you'd have to do to make that work, but it'd be the best solution. That said, if you go that way then we'll almost certainly get to another division comp meta that has a few widths that are better than others, with maybe some exception units for mountains.

Also, for the changes to division targeting in battles, it'd be nice if you could make the new process (whatever it ends up being) more readable in the UI. It has a huge impact on division setup but is completely invisible at the moment. It'd be nice if we could actually see what was going on and not just have a vague dev diary in the future tell us "We've made some changes to targeting, and we think they make larger divisions equivalent to smaller divisions now. Trust us!" before Bitmode digs into what's actually happening and we find out that its all sorts of jank.
 
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No No no please, I barely understood the vanilla troop systems, spamming 14/4s no please
I mean for what it's worth, it seems this is more geared towards making it so there is no dominant meta. Meaning that you are free from the shackles of 14/4s and are now allowed to experiment with other ways of designing your troops! (That said, I too will likely get my ass kicked now lol)
 
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Breakdown (numbers not final etc etc)
  • Plains
    • Standard 90
    • Reinforce 45
  • Desert
    • Standard 90
    • Reinforce 45
  • Forest
    • Standard 84
    • Reinforce 42
  • Jungle
    • Standard 84
    • Reinforce 42
  • Hills
    • Standard 80
    • Reinforce 40
  • Marsh
    • Standard 78
    • Reinforce 26
  • Urban
    • Standard 96
    • Reinforce.32
  • Mountain
    • Standard 75
    • Reinforce 25

Please update this when the patch goes live, or show it on changelog or something, so we could keep track of it D:

New tank meta is likely 42w tanks, and have 18w infantry as frontline. Mountaineer divisions will be 25w. You'll be avoiding fighting on marshes, anyways

Now I wonder, if things are to be even more fluid, will there be a new type of system to represent Kampfgruppens? They were basically a doctrine to mix up multiple divisions into one, temporarily, to better deal with urgent threats.
 
I also just remembered:
Weren't allied tanks much easier to repair than german tanks? Is a modifier like that also considered in the new reliability system?
Wouldn't that be entirely up to how you design them yourself in the designer rather than inherent to each nation? If you make them too over complicated like adding interleaved wheels like Germany did historically like shown in the tank designer dev diary you'll end up for example with reliability penalties.

Edit: forgot to add, the only Allied tank that to my knowledge was noted to be exceptionally reliable and easy to maintain is the Sherman and its derivatives since it was designed with overseas freight, fighting and maintenance in mind from the start.
To my knowledge Brittish and French tanks were about average as far as reliability goes, same for Italy and Japan. Or at least far less reports of Italian or Japanese tanks suffering heavily from breakdowns before even reaching the battlefield in the way the Panther was infamous for.
 
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No, then you'd have the Sahara and Arabic peninsula would be on one extreme of the spectrum, instead the Amazons and the Congo are on side and Siberia is on the other one.

I don't get it.
Deserts (e.g. Arabia and the Sahara) are much hotter during the day than during the night. The rainforests have less day-night variation IIRC. So I think the map shows temperatures during the Northern Hemisphere winter at Middle-Eastern night-time: probably 1 January 1936, midnight CET.

But I still don't understand what this has to do with combat widths.
 
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I'll agree with a lot of the previous posters:
The dev diary explicitly calls out the "59 piercing vs 60 armor, piercing does nothing" scenario as undesirable, yet the new system has the exact same problem?

No, because the issue there is the binary cutoff nature of the issue. The issue isn't that there is a point at which piercing does nothing, it's that there is a point where it suddenly flips from no effect to full effect. Now there will instead be a fairly broad transition zone. Whether the numbers happen to be equal at one end of that zone, the other end, or the centre, literally doesn't matter.
 
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stop spreading misinformation please, this isn't true at all. It's the meta for a reason you didn't find a secret special thing.
the meta is to build 20w infantry/special forces with arty rocket arty support companies on superior firepower because you can get way more soft attack/combat width that way. the reason why you do 40w tanks is that tanks have higher damage/cw than inf and can usually crit anyways. their defense and hp is also way lower so its very important to get high defense per division.
 
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One of the major things that make larger divisions like 40 width armor hit disproportionally harder than smaller ones is also how targeting and damage works inside combat in relation to the enemies defense. Essentially the larger divisions make more efficient use of concentrated damage as it punches through defense. To solve this we are doing a few things. First of all we are weighting the targeting towards wider divisions being more likely targets and also when picking targets to try and match it to have wider divisions spread damage over smaller rather than always concentrating it. They will probably still hit harder, but combined with width changes and other downsides of larger divisions it should make it less clear cut.
If a division targets 1 division, larger divisions end up being better despite their org pool disadvantage. But on the other end of spectrum, if the damage is spread "perfectly", then smaller divisions have no downsides at all, only upsides (the org pool AND support company advantage). Tiny divisions would end up being the ultimate meta winners, and stacking penalty will (for the first time in HoI4 history) start to matter. I predict such division meta would be somewhere between 2w - 4w o_O

So clearly the spreading must be (significantly) limited. I'm curious how you managed to solve this. :)
 
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Has that OOB button on the Tukhachevsky screenshot always been there? The one next to the 'select all' button
 
0:00 where?

In-game, which I think is based on GMT(+0), so midnight in London, or midday actually as it may be (I don't remember with certainty, but I think @cotne22 may be right with regards to the game starting at noon).

PDX seems to often take screenshots of this nature without unpausing. Even their combat screenshots and whatnot are usually from very early 1936, so if the game starts at noon, then maybe the Libyan temperature is a fluke/oversight or the screenshot just is from nighttime on another date.

No need friend, i now Finland has overall lower averages than Sweden, my point was that the map you posted doesn't quite prove your point, but you are still correct nevertheless.

Good, good.