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HoI4 Dev Diary - The Imperial Japanese Navy (AAR)

Hello, and welcome back to another Dev Diary from the frozen wasteland that is Sweden in January. Today, we will have another short AAR of a naval warfare scenario, similar to the one we did earlier about raiding and submarine warfare.


This was played as an MP game between me and Niall (@Ceebie), with me defending the Empire of Japan’s honor against Niall’s filthy American imperialists.


Starting as Japan, I immediately face a number of issues that should sound very familiar: I have very limited resources, particularly in terms of oil. This is now a much bigger issue as I can still happily build ships and airplanes and tanks, but I won’t be able to run them for free. However, if I want to upgrade my ships (and knowing Niall, I absolutely do), I will need naval experience, and China is unlikely to provide me with a lot of it. So I need to run training missions for my fleet, which gobbles up fuel at a rapid pace (I could only take out my main fleet units for a few brief weeks before the fuel situation became critical).


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At the same time, while I could trade for more oil, it will cost civilian factories which I desperately need to build up my own industry or to trade for steel to continue my military buildup. I decided to keep the trading for oil to a minimum in order to more quickly build up my industry and increase the size of my fleet.


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My first target is, of course, China, and we start the war with them in the middle of 1937. It quickly becomes apparent that I underestimate the Chinese. Fighting rages hard along the border for several weeks, and a number of naval landings that attempt to force the AI to draw troops away from the main front are quickly contained by local garrisons, but at least not pushed back into the sea. Part of the problem is that the fleets tasked with invasion support contain some of my battleships, which eat up absurd amounts of fuel, and my attempts to turn the tide through prolific use of air support eat into my fuel supplies even more.


By early 1938, we are slowly grinding forward and have managed to inflict serious casualties on the Chinese, but my fuel stockpile has shrunken to just 30 days of current use. I curtail air support to only support my main thrust and send the naval forces providing shore bombardment back to port. Progress slows, but eventually we link up with the landing forces, at least saving me from an embarrassing early defeat. The massive amounts of Land XP also allow me to run through the doctrine tree quite a bit faster than Niall could ever hope to. Sadly the war in the Pacific will not be fought on land.


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It would take until early 1941 for the Chinese to fall, even though the writing is on the wall by the middle of 1940. I blame the poor infrastructure and awful terrain in China - my leadership is, after all, beyond any reasonable doubt.


In the meantime, Niall has been quietly modernizing his fleet and has started his rearmament. While a good amount of his effort is spent on helping out the British in Europe, I have no doubt that he has something in store for me. While I was deeply engaged in managing the war in China, I received some out-of-game intelligence (Niall bragging in the kitchen that his destroyer swarms would annihilate me) that makes me realize that my fleet lacks some key capabilities. The starting Japanese light cruisers are fairly mediocre, most have been built during the 20ies and are not up to the task of winning a firefight against the likes of a Brooklyn Class cruiser with no less than 3 light cruiser battery modules. What I do have is a lot of torpedoes, and I invest a little into researching upgraded torpedoes and better launchers. The Japanese Long Lance national spirit gives me another perk, as it negates the enemy screening to an extend, which means that my torpedoes can hit his capitals even through 100% screening.


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So while I was slowly grinding my way across China, I also decided on my buildup strategy:


  • No new battleships, since they eat up a lot of fuel and I have enough to cover my carriers. However, I did later decide to build at least one Yamato-class as an insurance against Niall developing modern battleships.

  • A force of 4 light carriers. Japan starts with two (Ryujo and returning fan favourite Hosho), with two Zuhio class building. While these only carry 40 planes each, they will be used to provide cover for operations in and around the Dutch East Indies.

  • A force of 4 fleet carriers, with another force of 4 joining later. Akagi and Kaga will be joined by 2 more Soryu class carriers and form the main strike force in the Central Pacific.

  • A heavy emphasis on air defense and torpedoes. After researching dual purpose main armaments, I design a new destroyer class with improved AA and better torpedo armament. These are joined by a quartet of light torpedo cruisers from the Japanese focus.

  • Lots and lots of Naval Bombers to damage the enemy during the approach and pick off stragglers. Once the battle is fought, his damaged ships would likely try and find a close naval base for repairs, so having naval bombers ready to attack them in port would let me finish them off.

  • Once I identified the fleet’s weakness in defense against destroyers, I also designed a version of the Mogami Class heavy cruisers dedicated to light gun support. I built another 4 of these.

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The fleet’s main objective, however, is to provide support for landings to seize resource rich areas in the Dutch East Indies. To protect the sea lanes to and from these islands, I will need to secure the Philippines, and that is where things get a little dicey.


While I have little doubt that my forces can take over Sumatra, Java and Borneo, Malaya might be a tough nut to crack, and I know that Niall has already started to fortify the Philippines. I have researched amphibious armor well in advance and with China now pacified, I start to turn up production in an attempt to give my marines a bit more punch and hopefully allow me to seize a foothold even against heavy opposition.

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Thinking ahead, I also research improved naval bombers and the next generation of carrier planes. Once my main objectives are secured, I will use swarms of naval bombers to hold them down while I move my fleets to stage two and take on Australia.


To give myself some more time to buildup, I delay my attack on the US until early 1942. This allows me to form a second strike force of two fleet carriers (Shokaku and Zuikaku, both repeat Soryus as I was unable to scrape together enough XP to design an upgraded carrier).


The first battles are very encouraging. Whenever my patrols find one of his scouting units, my strike fleets sortie and make short work of them, Niall’s vaunted Destroyer swarms being no match for my upgraded cruisers and destroyers. I am somewhat confident that I can attrit his screening forces faster than he can replace them, which would eventually force his fleet to remain in port or eat absurd numbers of torpedoes.

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Things quickly turn a little chaotic as my strike fleets and patrols intercept a number of troop convoys. While I first thought that these were going to the Philippines, they instead turn out to be trying to seize islands in the Central Pacific. Things don’t go well for him, as he has decided to keep his battleships and carriers on strike duty instead of covering his invasion convoys. Several divisions are effectively destroyed at sea, and the remains fail to gain any footholds.


At the same time, my invasions in the DEI, supported by the old battleships Ise and Hyuga, have run into stiff opposition while attempting to land in Borneo. I shift some tactical bombers into the theater to help break the stalemate, and we are starting to make progress. The two-pronged assault succeeds in establishing a foothold, but it is a reminder that Niall has not been idle and is ready to fight for every inch of ground in this vital area.

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While my marines still struggle to make landfall in the Philippines, a bigger drama unfolds in the Bismarck Sea. Niall has finally unleashed his main strike force, after one of his patrols found my carrier fleet.


The Battle of the Bismarck Sea does not go particularly well for the Imperial Navy. With several battleships detached for minor repairs, the US Navy breaks through my screening units and manages to do an end run on my carriers, sinking all four for no capital ship loses on their side. The survivors straggle home, many ships badly damaged during the ferocious engagement as my battle line attempted to screen against the full might of the US battlefleet.

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However, Niall’s victory has come at a steep cost. Most of his battlefleet is badly damaged, and he has nothing to follow his success up with. More than that, I still have 6 carriers in reserve (2 fleet, 4 light), and several hundred naval bombers scouring the Bismarck Sea means that he has to risk his battleships again to sail them to safer harbours for repairs. Several of them take further damage as they retreat, many of them out of the battle for almost a year.

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While Niall has blunted my offensive power quite severely, he has nothing to interfere with in my operations in the DEI, which were the main objective. Trying to use the Philippines as an unsinkable aircraft carrier has become next to impossible as trying to supply it with fuel would cost him too many convoys and tank his war support. The Japanese conquest of the southern resource area won’t quite be the lightning strike it was in history, but it is as inevitable as the rising of the sun.

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With hindsight, my performance in the naval war thus far comes down to:

  • Lack of radar allowing Niall to get the drop on me in a critical moment

  • Lack of training due to fuel concerns

  • Insufficient coverage of the seazones with naval bombers failing to disrupt the enemy on the approach

  • Not enough screening vessels to protect my carriers against his battle fleet. Although Yamato sunk several ships and survived to fight another day, spending the same amount of 3 heavy cruisers would likely have yielded better results

  • Good performance of my light forces when engaged on equal terms

That is all for today. Tune in at 1600 CET for another stream with an indepth look at fuel.
 
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My humble opinion on "Pearl Harbor":

Pearl Harbor should be a Decision that Japan can take, with ships stationed being temporarily damaged. If Japan players choose Historical Focus option, damage is limited to just any warships stationed there. Priority being heavy warships. There's also a random (tiny) chance that a "3rd attack wave" could have been taken, with more damage on fuel depots and dockyards in Hawaii, and possibly a temporary decrease on decryption (to simulate an attack on the US Pacific Fleet Headquarters itself and the naval code readers)

Unlockable only when taking the "Secure the Philippines" Focus. Naturally, this comes at a cost of increased War Support for the Americans (historically). Much more when the 3rd Attack Wave happens.

To those wondering why I suggest this, I am simply in favor of giving more perks for the IJN despite the main focus on the USA and UK. This IS a naval-themed DLC, after all. Without the "Pearl Harbor Gambit" Focus, I honestly think Japan is already toast to begin with. At the very least, the unlocked decision should give Japan an early-game historical advantage. They can be pushed back, however, as Japanese ship losses become too much, while American industrial production and decryption techniques improve massively. (Historically)

I could argue a similar approach for the Asiatic Fleet in Manila, the British Far Eastern Fleet in Singapore, or even the Soviet Pacific Fleet in Vladivostok. After all, the Japanese have a precedent for surprise attacks. *cough* Port Arthur *cough*

I dunno, just my 2 cents. :)


DDs and streams said that port strikes are now possible war winning missions, which is why several mechanics have been adjusted.

In any Case, I guess the 100% mission efficiency for port strikes and the other boni for the IJN unlocked by the "Tora tora tora" decision would allow for a Pearl harbour like attack wherever the USN is located and thus relying on the player's skill to locate and destroy the enemy.
 
Can you describe in more detail how to use player skill to locate an enemy navy in port before going to war?
With the spotting mechanics unclear to this moment, I can only speculate:

A) using long range patrols to check on likely target harbours, akin to land armies getting intelligence on what's across the border
B) thinking very hard where the enemy would place his ships to be able to engage with, but also protect his assets. Something with AA, high Port Level, good infrastructure, an airfield and far enough away from enemy airpower, while as much forward as possible.
In a historic scenario, either Pearl harbour, or very maybe the phillipines.
C) have patrols detect the enemy and pursuit a beaten enemy fleet to its port.

To be clear: this is not a way to gather perfect intelligence - but a close to historical one, the japanese intelligence did not know the american Carriers where out of port either.
 
Pearl Harbor should just be a news event triggered by a port strike at Hawaii. Other implementations do not make sense for the current gameplay we've seen of 1.6.
 
In the stream today @Archangel85 and @Ceebie mentioned that the pearl harbor focus on the us tree went the way of the dodo. they also said a US player would be really pissed if the player lost 9 battleships at the completion of a Japanese focus. Of course that same focus would give the American 100 percent stability and 100 percent war support. So PDX, what is wrong with a little bit of IRL?

I have never noticed my BB in Pearl Harbor being auto-sunk just by selecting a focus. It ramps up tension, and ensures Japan declaring war.

Is it a Japanese focus that lets them auto-sink USA capital ships?

Edit: okay, yes, Japanese focus.

I have been unknowingly gaming the system by removing the ships after getting the gambit focus... though I've had cases of NOT removing them, and still no auto-sink.
 
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DDs and streams said that port strikes are now possible war winning missions, which is why several mechanics have been adjusted.

In any Case, I guess the 100% mission efficiency for port strikes and the other boni for the IJN unlocked by the "Tora tora tora" decision would allow for a Pearl harbour like attack wherever the USN is located and thus relying on the player's skill to locate and destroy the enemy.

Oh, I missed that part. So I guess the Pearl Harbor strike can now be replicated in-game as long as players know where the enemy fleets are based.

With the spotting mechanics unclear to this moment, I can only speculate:

A) using long range patrols to check on likely target harbours, akin to land armies getting intelligence on what's across the border
B) thinking very hard where the enemy would place his ships to be able to engage with, but also protect his assets. Something with AA, high Port Level, good infrastructure, an airfield and far enough away from enemy airpower, while as much forward as possible.
In a historic scenario, either Pearl harbour, or very maybe the phillipines.
C) have patrols detect the enemy and pursuit a beaten enemy fleet to its port.

To be clear: this is not a way to gather perfect intelligence - but a close to historical one, the japanese intelligence did not know the american Carriers where out of port either.

Good ideas. By "long range patrols", you mean land-based naval bombers or just about any warplane type within range?

It would be nice for Paradox to add more mechanics to further enhance the Pacific War in-game :)

Also: I can't help but re-read the DD while listening to Japanese themes of Pearl Harbor (2001) and Battlestations: Pacific as background music. :D
 
In the stream today @Archangel85 and @Ceebie mentioned that the pearl harbor focus on the us tree went the way of the dodo. they also said a US player would be really pissed if the player lost 9 battleships at the completion of a Japanese focus. Of course that same focus would give the American 100 percent stability and 100 percent war support. So PDX, what is wrong with a little bit of IRL?
IRL?
"The Japs just decided we we lost nine capital ships. No, there was no battle, they just decided the ships be sunk, and so they just spontaneously combusted".

Nope, I don't consider that good gameplay. Sounds more like how DH (I think) would always auto-resolve the winter war with the historical outcome, regardless of how well the player did.
 
Edit: this is response to @Vanadium23's post, a few posts above mine.

Very undecided on Pearl Harbour. The senate idea I actually like, but I dislike the idea of giving the Japanese player "free kills" in the form of a decision.

Also consider this isn't a railroaded game, and Pearl Harbour takes place nearly six years after game start. Trying to make specific historical battles happen this late in the game is always going to be tricky. Instead, you're going to have memorable battles and events that didn't take place historically, but which shape your particular campaign.

Now, if either the devs or modders made a Day of infamy bookmark where the US started with crippled ships at Pearl and a Japanese task force close by, that would be a different story, of course.

If the Japanese player has an advantage carrier wise at the beginning of a conflict with the US, given fuel and other resource bottlenecks it behooves them to make an effort to knock out the US fleet at one go. Even if it's not finished off, the damaged US surface combatants would have to be repaired at the cost of dockyards... which means new ships not coming online. And with the increase in duration of new capital ship construction, this makes the odds of a Pearl Harbor type attack more likely. And if the US fleet lives on the West Coast, invade Hawaii!
 
A) using long range patrols to check on likely target harbours, akin to land armies getting intelligence on what's across the border
In the current version of the game enemy fleets in port are invisible, and I don't think they have revealed anything suggesting that will change as far as I am aware at least. I also hope there will be some way to spot enemy fleets in port though other than through trial and error with bombers, but if we are talking peacetime I don't think skill would be involved no matter how that would be done, just a question if you prepare or not.

B) thinking very hard where the enemy would place his ship...
So guessing then? I don't think logic applies when your looking for where the AI has their fleet though, but guessing might work in player vs player.

C) have patrols detect the enemy and pursuit a beaten enemy fleet to its port.
That doesn't sound like something that could lead to a Pearl Harbor style surprise attack, which is what the question was about.
 
Every week i come here filled with hopes and dreams about the release date and then my dreams are crashed. And as i'm beaten down, i find the courage to stand up, take a deep breath and whisper to myself: "One more week"...
 
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Fair enough.

As I mentioned, little Data to support any prediction, but a "Pearl harbour" in every game makes little sense.
Without any mechanic for spotting fleets in port, it would be Impossible, either.

Problem is vs Humans, a Pearl harbour would be anticipated anyway. Vs AI, well, you don't have to rely on it.
Tricky to solve, but Intel + Tora tora tora spirit works best imho.
 
Oh, I missed that part. So I guess the Pearl Harbor strike can now be replicated in-game as long as players know where the enemy fleets are based.



Good ideas. By "long range patrols", you mean land-based naval bombers or just about any warplane type within range?

It would be nice for Paradox to add more mechanics to further enhance the Pacific War in-game :)

Also: I can't help but re-read the DD while listening to Japanese themes of Pearl Harbor (2001) and Battlestations: Pacific as background music. :D


Long range patrols would be subs or maybe CLs. If the enemy puts his battle fleet in range of NAV, well, damn his luck!
 
This could be the perfect jump in for the next DLC, dealing with espionage and reconnaisance methods:cool:
 
The thing about Pearl Harbor in the game is that nowadays the game cannot represent it's historical importance for the US Navy.

1) The first reasons for the Americans to station it's Pacific Fleet in Pearl Harbor is a matter of supply. The Naval Base had important fuel, munitions and food depots that could be delivered to the fleet in a very short time, while under other conditions that supply would have to be brought from California.

2) If you're expecting to engage an enemy fleet in the Pacific then it would be stupid to base your main strike force in California/Washington. It suppose to much travel, so unless the battle rages for a week their ships would not arrive in time.

Because of both reasons the US had to station its main Pacific Fleet in Pearl Harbor while smaller task forces had bases in islands such as Midway. And if the game could get the naval supply and battle timing right any American player would have to base its fleet in Pearl Harbor risking a Japanese port strike, even whithout the focus.
 
Why not have fuel in months instead of decimalized in years? The former is easier to calculate how long it will last. The latter as is currently requires to do the math every now and then.
 
Nothing more disappointing than reading and amazing in-depth dev diary to then seen all the comments are childish "release date when?" comments and the order i which they placed.

I disagree with you in calling all of those who ask for a release date as childish. They are completely justified for their complaints as we are currently in the longest wait time between expansions. Here are the statistics:

Previous wait times:
Together for Victory
15 Dec 2016 to Death or Dishonor 14 Jun 2017 = 181 days
Death or Dishonor 14 Jun 2017 to Waking the Tiger 08 Mar 2018 = 267 days

It is currently January 31st of 2019 which means that the time between the previous DLC and now is over 319 days. So far, this is the longest gap between DLC and we don't even have a release date yet. It has almost been a YEAR since the last large expansion. When you compare HOI4 with the development of Stellaris, this disparity in release dates becomes increasingly apparent.

Stellaris wait times:
Synthetic Dawn
(Story Pack) 21 Sep 2017 to Apocalypse (Major Expansion) 22 Feb 2018 = 154 days
Apocalypse (Major Expansion) 22 Feb 2018 to Distant Stars (Story Pack) 22 May 2018 = 89 days
Distant Stars (Story Pack) 22 May 2018 to MegaCorp (Major Expansion) 06 Dec 2018 = 198 days

The reason for even bringing up Stellaris in the first place is due to the fact that they are both Paradox games. Granted the market and dev teams/engine differ, it's still interesting to see how both HOI4 and Stellaris compare in relation to expansion dates. One can argue that one game is quite consistent with its updates and the other is not. Now defend as you want but you cannot deny the fact that inconsistency and upward waiting curves don't necessarily work to keep the consumer on-board. I love to see these Dev Diaries but considering I've already put money into this DLC months ago, I'd like to get a date at-least or even just a reason for the delay (bug fixes aren't the best explanation). Hope this clarified the reasoning behind many people who are simply upset with the current state of HOI4 updates.