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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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This is looking more amazing with every reveal.

Note to the "release date when" crowd; you're getting more news than those of us who play Star Wars Armada. Been about a year since expansion info was announced and nothing but a leak or "leak" since. I'm looking forward to overthinking ship/fleet designs in HOI4 like I do in Armada.
 
"filthy American imperialists" - Plays as EMPIRE of japan lol
 
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.

As someone who played Japan relatively recently, the new Japanese focus tree grants you no naval experience (and only 10 army experience), you will basically be entirely dependent on training and the early war with China for your exp.

One of the things about the new version is that the new naval designer is not like the old variant system, where dumping naval exp into it just made it flat out better. It is going to work more similar to the army designer, so, designing the 'perfect' Shokaku will probably be a lot cheaper, but on the flip side, you will be required to spend some naval exp on anything you planned on fielding.

I suspect one of the major decisions facing a Japan player will be wither to stick by the Washington Naval Treaty, or abandon it. You can probably game the system by spending exactly the maximum cap on ships, and then when the war starts and the limits are removed, refit to a much stronger ship.

Of course, one of my old longstanding questions is:
Is the Carrier penalty still in the game?

If so, than old CV1s become a liability and thus it might actually be useful to convert them back to battleships/cruisers.

Will you be able to license nation specific technologies, like the panzershiff or cruiser submarine

More than likely you can, you just will not be able to design them yourself.
 
"filthy American imperialists" - Plays as EMPIRE of japan lol
No no no, when we do it, it's liberating people of in this case Asia, but when they do it they are warmongering imperialist scum. :)

also I'm pretty sure that having emperor or king doesn't make you automatically imperialistic. (e.g. modern Japan, they aren't imperialistic, are they?) it only makes you imperialist when you want to conquer random nations just because you're bored.
 
It's really disappointing to see how many people have only been asking about the release date, or whining about the nature of the dev diary. I found this update to be helpful, personally, and it was definitely nicer than having no update at all.
 
Looking at the one naval battle you showed us. it looks like the following:

1. Planes are used after DDs find the enemy.
2. DDs and CLs are scouting. You call it screening but its really scouting.
3. Battleships delivered the killing blow on the carriers.

I want to be able to do the following:

1. Build naval carrier and land based planes scout, find, and kill the enemy. Planes should be able to sink carriers without surface fleet assistance.
2. I want to build a modern navy in the game without battleships and be successful. I should be able to do this.Battleships became obsolete for naval combat during WWII. They were not that effective in the battle of Leyte. Had Taffy 3 been under the command of a naval air admiral and not MacArthur, some of the aircraft would have been armed for ship combat and some armed to support the landings. Taffy 3 would have been even more successful against the IJN battleships and cruisers. That is why in modern navies, there aren't any battleships.
3. Build Cruisers, Light cruisers and destroyers that screen carriers and/or protect SLOCs.
3a. CLs and DDs protect SLOCs.
3b. CAs, CLs and DDs screen carriers in the rear not the front of the battle.

If your DLC does these three things above, then you have succeeded in building an excellent, comprehensive, grand strategy WWII game and will have made my day. I am hoping that what I saw in the AAR is a McArthur trying to be an Admiral and what I want to see is Nimitz planning and leading the Naval battle. I am hoping that a good respectable Admiral playing the game can mimic Nimitz and that the mechanics of the game, that we cannot mod, allow it.
 
As someone who played Japan relatively recently, the new Japanese focus tree grants you no naval experience (and only 10 army experience), you will basically be entirely dependent on training and the early war with China for your exp.

One of the things about the new version is that the new naval designer is not like the old variant system, where dumping naval exp into it just made it flat out better. It is going to work more similar to the army designer, so, designing the 'perfect' Shokaku will probably be a lot cheaper, but on the flip side, you will be required to spend some naval exp on anything you planned on fielding.

I suspect one of the major decisions facing a Japan player will be wither to stick by the Washington Naval Treaty, or abandon it. You can probably game the system by spending exactly the maximum cap on ships, and then when the war starts and the limits are removed, refit to a much stronger ship.

Of course, one of my old longstanding questions is:
Is the Carrier penalty still in the game?

If so, than old CV1s become a liability and thus it might actually be useful to convert them back to battleships/cruisers.



More than likely you can, you just will not be able to design them yourself.

I do believe that they should get naval xp from some of their naval focuses in MtG then. It will now be quite difficult to gain xp compared to the US who has 3/4ths of the oil in the game and who could train their fleets everyday in peacetime. Japan will really get screwed here if the only way to get naval xp is from their small skirmishes with China, and very few training sessions allowed because of lack of oil.

This is something easily changed by adding up what they used to have which was about 125 naval xp from the old focus tree. That or I guess I could just get one of the naval advisors, but then so can anyone else.

Please bring back the naval xp for Japan through their focuses - Paradox!!
 
index.php


in Dev Diary about Fuel and Motorized Arty this screen had A & P for oil need "Active need and potential need are now represented with “A” and “P,”" See Below:
index.php



Now it has C: and M: for oil need in the same screen for Japan see first picture....why?
 
in Dev Diary about Fuel and Motorized Arty this screen had A & P for oil need "Active need and potential need are now represented with “A” and “P,”" See Below:

Now it has C: and M: for oil need in the same screen for Japan see first picture....why?


C for current consumption and M for maximum consumption is less ambiguous I guess.
 
...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.

You are also missing how much more micro these decisions are going to take. Bye bye 5 speed.

Change, adapt, or die. A meta is only good until the next DLC or patch.

Can you tell your fleet to retreat if the situation looks bad?

99.9% certain I saw that mentioned previously. And you can sort of do it now, depending upon the differences in speed. But the new naval mechanics should have this mechanism. Assuming you are fast enough to get away, and haven't suffered damage slowing you.

Wonder if there is a "Ships Scatter and Proceed Independently" order, ala PQ 17?

Will you be able to license nation specific technologies, like the panzershiff or cruiser submarine

Don't see why not? You can't get nation specific bonuses, but building plans have always been fair game iirc.
 
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Will the AI be able to manage the oil stockpiles and fleet squadrons? The AI currently cannot tell the difference between a mountain fortress and an open field, and will routinely suicide a million soldiers into a line of fortifications. After the debacle that is the Stellaris AI in the current patch, I'm not terribly keen on purchasing any more DLC with terrible AI.
 
The AI currently cannot tell the difference between a mountain fortress and an open field, and will routinely suicide a million soldiers into a line of fortifications.

This is not correct. I played France yesterday with heavy fortifications and the AI did not bang its head on my forts.
 
It only took a full year to implement what unpaid modders have already done and what was alreasy in the previous game. YAY WE LOVE YOU PDX ONLY $19.99

I suspect you are a half glass empty person.

Or perhaps you don't realise that modders modify while game designers design. There is a huge difference between changing a group of basic game designs and modding an existing structure.

You seem to have a lot of Pdx games - don't you think it better to support one of the few companies that produces computer games that require thought rather than reflexes? To me $19.99 is a small price to pay for the many hundreds of hours of enjoyment I get from Pdx games. That is far less than the price of a meal, just over the cost of a movie ticket.

I am not some fanatic supporter of Pdx and have been quite critical of HOI4 - I have hardly played vanilla and I pre-bought the whole package. The game is finally looking as though I can play it through. But I am not unhappy at Pdx. In a world where Fortnite and its clones rule, I am grateful for what I get. I am also grateful for unpaid modders - I have played BI since it first put out its HOI3 mod.

Having said all that, my impatience for that which must not be named is at bursting point. Give me release!
 
This is another good diary. These game recaps give us a lot of detail that doesn't always come across in traditional entries.

I hope you guys are reading comments like Farquarsen's here...

I want to be able to do the following:

1. Build naval carrier and land based planes scout, find, and kill the enemy. Planes should be able to sink carriers without surface fleet assistance.
2. I want to build a modern navy in the game without battleships and be successful. I should be able to do this.Battleships became obsolete for naval combat during WWII. They were not that effective in the battle of Leyte. Had Taffy 3 been under the command of a naval air admiral and not MacArthur, some of the aircraft would have been armed for ship combat and some armed to support the landings. Taffy 3 would have been even more successful against the IJN battleships and cruisers. That is why in modern navies, there aren't any battleships.
3. Build Cruisers, Light cruisers and destroyers that screen carriers and/or protect SLOCs.
3a. CLs and DDs protect SLOCs.
3b. CAs, CLs and DDs screen carriers in the rear not the front of the battle.

...and others like it that have come up in previous threads. The naval updates, ship builder, and fuel system look really promising, but carriers should be able to run from surface ships with greater ease. The instances of carriers being sunk by surface vessels were flukes, with aircraft and the submarine being the true counter to the carrier.

With the amount of thought and effort being put into this DLC it not only bodes well for Man the Guns, but also is really promising for the Soviet update and land combat rework when you eventually tackle For the Motherland 2.0.
 
It's really disappointing to see how many people have only been asking about the release date, or whining about the nature of the dev diary. I found this update to be helpful, personally, and it was definitely nicer than having no update at all.
They specifically asked in the tweet accompanying the dev diary "let us know how you feel about this style of Dev Diary". And why would the alternative be to have no update at all?