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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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The Torpedo Cruiser focus unlocks a special hulltype that has more slots available for torpedoes.

BTW, I wonder if there are various techs unlocking historical ship models after a hull is unlocked. For example, if the "Cruiser Hull 1940" is researched, are there sub-techs for unlocking CL(Cleveland), CA(Baltimore) or AA(Atlanta) variants, or I need to design them myself?
 
Does state/land AA now reduce damage that can be done against ships in portstrikes?
yea, they are now subject to disruption etc. We also did some balance stuff with cooldowns and "combat width" as port strikes are generally now more powerful with navies spending more time in ports
 
To suggest that the Empire would have to resort to such desperate tactics displays a lack of commitment to the war effort and lack of faith in our inevitable victory. Shameful.
Sure the Japs will win... and my name is Robert E. Lee. Anyway decent DD and I now know that the achievement DD is still far away which means the release is still a ways away and that’s alright (I’ve been waiting to play the United States of America for a long time now and still waiting because I want to make sure that I actually want to play the USA when MTG comes out but I am now a man of great patience so I am being quite patient right now considering that coming around to a year now).
 
BTW, I wonder if there are various techs unlocking historical ship models after a hull is unlocked. For example, if the "Cruiser Hull 1940" is researched, are there sub-techs for unlocking CL(Cleveland), CA(Baltimore) or AA(Atlanta) variants, or I need to design them myself?

You'll have to design them yourself. It does allow you to make ships like a heavily armored AA cruiser, though, so I think it adds a lot of depth.
 
i remember the first time i realized planes need supplies
my germans in konigsberg had very bad supply status
and i started to think that maybe those 2k planes there may affect supply a bit

also if you don t have any idea for dd, i think it would be cool to see the notable changes to oob (new ships added at the start?) and the focus trees. earlier you mentioned obvious changes to naval stuff in the focus trees, such as special hulls (cruiser subs in today's stream) yet i am also interested in the changes in other naval focuses, or whether were there special hulls other than panzerschiffe, coastal bb, torpcruiser and cruiser sub? or changes to ships in production?
 
Please go back to the old style of dev diaries. I want news about the development of the next patch (and DLC). If I wanted to read AARs I'd go to that sub-forum.
 
@Archangel85 Also I would just like to know for sure if you guys will be going over the further changes you’ve made to the USA focus tree, the borders, States, and etc?
 
Saving 90 days on research is nice, but there's no way that's worth forgoing engine 5 on your light tanks or armor 5 on mediums.

Indeed. You can already easily finish your land doctrine tree in 1940 with 24/7 research on it. Maybe even in 1939 if you have 30 days of research saved each time you start researching a doctrine tech. Definitely not worth using XP on if you're producing equipment that also uses XP.

What they should have done IMO was severely nerf doctrine research. Giving years to the techs like in previous HoIs would be a major improvement, especially when the later techs are supposed to represent late-war developments in doctrine, yet good players will have them in 1940. Then spending XP on them might become a sensible choice.
 
i forgot to ask at today twitch, any news about the Paradox event in Berlin this year?

Ive to plan it as early as possible cause its in "REAL LIFE"! (i hope you can understand)

Q: Whom from hoi4 team will be in Berlin,too? Can we play hoi4 at event? Does wed need to bring our own computers?
[pls excuse for posting here but iam in a little hurry so hadnt time to find the rightplace]
 
Indeed. You can already easily finish your land doctrine tree in 1940 with 24/7 research on it. Maybe even in 1939 if you have 30 days of research saved each time you start researching a doctrine tech. Definitely not worth using XP on if you're producing equipment that also uses XP.

What they should have done IMO was severely nerf doctrine research. Giving years to the techs like in previous HoIs would be a major improvement, especially when the later techs are supposed to represent late-war developments in doctrine, yet good players will have them in 1940. Then spending XP on them might become a sensible choice.

Well they did say they increased the base time for doctrine research now (with the option of xp to drop it again). They specifically didn't want it to be normal to finish the doctrine tree in 1940 for everybody
 
Are there any plans to increase the information concerning the navy in the nation view? Currently I do not know if UKs 150-200 ships are all battleships or simply a massive pile of submarines. Eventhough one would not know exact numbers the nations during WW1 and WW2 had a somewhat good idea of especially large ships the enemy was fielding/constructing. This, especially in the prelude of WW1, caused a naval arms race. Would be a super interesting element of the naval game, especially with the changes in Man the Guns.

In the example you just posted, how do you know you met the US main fleet (except experiance playing them?) All you know is that the US has for example a total of 120-150 ships, you met 9-15+?. He might have 20 more battleships waiting for all you know. If you knew the US only had between 10-20 Battleships and you met 10 of them, you could make an informed decision after the battle, knowing you damaged at least half their battleshipfeet, probably more.
 
...I think one of the things this community has not put much thought into is just how much this DLC is going to disrupt the multiplayer meta. Right now the MP meta focuses a lot on spamming fuel-heavy units. Tank spam, plane spam, run heavy TDs in line infantry divisions to turn them into space marines.

This DLC is going to kill all of that.

Even countries that have more oil than they know what to do with, the refining mechanism prevents them from magically utilizing all that oil, so even oil-heavy countries like the Soviet Union and United States will run out of fuel if they try to spend it all at once.

Basically, now there is an incentive to actually use non-fuel consuming units in your OOB.
 
run heavy TDs in line infantry divisions to turn them into space marines.

No-one's done that in serious games since 2016 because it's so trash it's countered by a single support battalion of AT. Huge waste of IC.
 
With the loss of 4/6 of your fleet carriers, it seems a forgone conclusion that, while you might be able to take out Dutch Indonesia, there will shortly be a point where American production overpowers you and your 2 fleet and 4 light carriers will face around 8-10 US Fleet Carriers, which will destroy any other offensive naval power you have.

That was a complete defeat, comparable to Midway. Also, as Japan, 100% of all of my naval xp before war with the Allies gets saved and then used for the Shokaku class carriers in 1940. I understand things are different now that you have to use naval xp now to design all of your ships. I don't know, I think this puts you in an even more precarious situation, but to win the war means to win at sea, and that means carrier power. Nothing else even comes close to it. I would have started designing those cruisers and destroyers with the war xp, not the xp leading up to it. You also used to get chunks of xp from focuses. I am not sure how much that has changed with WtT though.

Anyhow, my last paragraph is all moot because this was basically a DD describing what you can do now with MtG, and I fully get that. I'm just pointing out my strategy to win with the Japanese navy. Putting 120+ aircraft on my Shokaku fleet carriers is, or was my main strategy when it comes to Japanese fleet designs.
 
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