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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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Thank you for this DD and report on the current state. It*s nice to hear that fuel now has a proper impact on strategic choices. Hopefully, this will make the game more immersive and less about spam. I'm still concerned about naval bombers and whether the ai will still dogpile its air forces, deploy them across the globe with no repercussions. I would really hate the launch of the primary naval DLC for this game to be ruined by naval bomber spam and an AI that dumos the entire allied airforce in Belgium. It would be nice to see a limited manpower pool for the air forces as well just to be sure.
 
@RommelTheDesertFox This is an international audience. All folks here have relations that died in WWII mostly in defence of their respective motherlands. Have respect for them as well. Having served in Japan, I can assure you WWII was painful for them in ways you cannot understand. Also please leave Vietnam out of this, its totally irrelevant to the forum and this thread.
 
@RommelTheDesertFox This is an international audience. All folks here have relations that died in WWII mostly in defence of their respective motherlands. Have respect for them as well. Having served in Japan, I can assure you WWII was painful for them in ways you cannot understand. Also please leave Vietnam out of this, its totally irrelevant to the forum and this thread.
I didn’t have any other good comparisons at my disposal and I apologize for attacking you earlier.

EDIT: also thank you for your service sir.
 
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?


Would be nice for there to be an orderly retreat button and a scattered every man for themselves retreat button.
 
You don’t understand the fact that even the devs themselves say that HOI4 is a historical game so why not just have Pearl Harbor AT LEAST since it was a world changing event and the only one that could be worked into HOI4 well.

The problem with working single battles into HOI4 is, to what I call, the butterfly effect. Every single battle fought in WW2 had a ton of very specific events leading up to that battle. Realistically speaking, even minor, RNG-related changes can cause massive effects on how events play out. These effects amplify over and over as those changes cause even bigger changes down the road, eventually leading to a world war two that is virtually unrecognizable in the details (and possibly even the outcome), even if everyone went for historical focuses.

Reenacting pearl harbor in that light is virtually impossible within the frame of HOI4's mechanics. The initial Japanese advantage is already modeled anyway through the Tora Tora Tora decision, which gives Japan some very strong buffs.
 
As long as island hopping is implemented in a good way, I'm happy. You should have to slog through the Pacific, not just make a beeline for Japan.

Edit: I hope MtG limits the garrisons on islands. Europe Engulfed (board game) limits troop deployment in cities, on Gibraltar, and on islands like Malta, and it greatly improves gameplay.

HoI4 should have "tiers" of islands that permit a certain number of divisions/battalions.

AI could be an obstacle, though, I suppose.
 
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As long as island hopping is implemented in a good way, I'm happy. You should have to slog through the Pacific, not just make a beeline for Japan.
I agree with that fully as allowing people to go straight for Japan is rediculous especially across all of that open ocean.
 
The problem with your suggestion is how does the game determine the difference between a garrison division and a mustering invasion force.

Of course, the main problem with naval invasions, and the root of all of these issues, is that supply convoys can sail through sea zones with enemy naval superiority without much issue. Oh sure, you would have a steady attrition of convoys, but as long as you have enough replacements (and convoys are dirt cheap), the supply route still works at 100%.

This is one of the lynchpins behind cheesing ground forces past enemy naval superiority. The other lynchpin being that naval forces set to 'do not engage' are unattackable (I have had a US player sit the entire Pacific fleet off the coast of Japan, and I could not do shit because of that), and the final lynchpin being that naval forces set to 'do not engage' can still get naval superiority.
 
The problem with your suggestion is how does the game determine the difference between a garrison division and a mustering invasion force.

Of course, the main problem with naval invasions, and the root of all of these issues, is that supply convoys can sail through sea zones with enemy naval superiority without much issue. Oh sure, you would have a steady attrition of convoys, but as long as you have enough replacements (and convoys are dirt cheap), the supply route still works at 100%.

This is one of the lynchpins behind cheesing ground forces past enemy naval superiority. The other lynchpin being that naval forces set to 'do not engage' are unattackable (I have had a US player sit the entire Pacific fleet off the coast of Japan, and I could not do shit because of that), and the final lynchpin being that naval forces set to 'do not engage' can still get naval superiority.

One of many reasons I would sooner play China than Japan.

Suppose hypothetically that HOI4 worked like other Paradox games, & provided world tension were above a certain threshold (to prevent someone jumping the gun in 1936) you could declare an abrupt & unjustified war for, say, a penalty to stability & war support, &/or a vastly increased political power cost compared to simply justifying the war. It wouldn't fix issues with emulating historical surprise attacks which a player knows are coming, but if there were even the unlikely specter of an aggressive or particularly hateful neighbor trying to get the jump on you, it might disincentivize the sort of absurd tactics described above, while still discouraging routine or careless use of the surprise attack mechanic. It would of course be a bit ahistorical for there to really be a surprise attack with no warning whatsoever, but at least it could be pulled off with the enemy actually seeming surprised, rather than acting like they'd seen Operation Barbarossa coming all along.
 
I agree with that fully as allowing people to go straight for Japan is rediculous especially across all of that open ocean.

Kinda reminds me of those times when AI Britain ended up landing in Hokkaido and southern Sakhalin... in 1942!

Seriously though, an improved island-hopping campaign (and revamped port strikes) will do to make the Pacific War in-game more challenging for all players. (Like historically)
 
As I see from quick look the ships are in zones. That's awesome. I'm thinking that the same could be on the land. Artillery/ heavy guns, field guns, mortars, trenches, machine gun nests, shock groups digging through with granedes, German elastic defense, psy-attacks. Battle window can turn in to a mini-map of a battle.
 
The problem with working single battles into HOI4 is, to what I call, the butterfly effect. Every single battle fought in WW2 had a ton of very specific events leading up to that battle. Realistically speaking, even minor, RNG-related changes can cause massive effects on how events play out. These effects amplify over and over as those changes cause even bigger changes down the road, eventually leading to a world war two that is virtually unrecognizable in the details (and possibly even the outcome), even if everyone went for historical focuses.

Reenacting pearl harbor in that light is virtually impossible within the frame of HOI4's mechanics. The initial Japanese advantage is already modeled anyway through the Tora Tora Tora decision, which gives Japan some very strong buffs.
i agree, model a real flow is nearly imposible, even then somethings could be employed as a phoney war, dont let get italy until fall of paris or try something with china (8 years of resistence try to hold the fight but you could add some kind of truce and start a continous bordert war to emulate the sino japanese war after a cosiderable advance).
But this are more like political things, simulate north afrika campaings is imposible, and the better way model something as torch is make apppear units in marocco coast. Similar issue with perl harbour.
 
As long as island hopping is implemented in a good way, I'm happy. You should have to slog through the Pacific, not just make a beeline for Japan.

Edit: I hope MtG limits the garrisons on islands. Europe Engulfed (board game) limits troop deployment in cities, on Gibraltar, and on islands like Malta, and it greatly improves gameplay.

HoI4 should have "tiers" of islands that permit a certain number of divisions/battalions.

AI could be an obstacle, though, I suppose.
in files theres tiers of island clasification but i dont know if they have triggers for that tag in events or posible garrison command.
 
Saying that it's a disaster there is no Pearl harbor in HoI4 is a bit like saying that it's a disaster there is no guarantee the German 6:th army will be encircled and destroyer in Stalingrad in HoI4.

Instead of complaining about lack of hardcoded events, NFs or decisions, we should be asking for game mechanics that make these situations more likely and effective moves if a historical path is followed. Where are the mechanics that have it make sense for USA to base their fleet at Pearl harbor as a deterrent or Political statement, that prevents USA from fortifying the entire Pacific and that makes an historical surprise attack a logical path for Japan to take?

Mechanics like:
  • Airplanes on the ground can be destroyed in large numbers when a nation at peace is surprise attacked by Axis aggressors ( Like in Soviet or for USA )
  • Port/Airbase Strikes by Carriers are prepared like invasions ( hit hard but once, instead of small attacks several times per day ) and can be launched as an opening move when declaring war
  • Such missions are coordinated automatically by the game to all hit their targets at the same time, or to progress to a "launch point" close to the target and wait for Declaration of War
  • It is possible to use decryption, espionage or scouting by air/submarines to locate enemy warships at port so you know where to target portstrike missions
  • Political and Strategic reasons that cause USA to base lots of warships in their Main Pacific base at Oahu
  • Fuel situation in Japan that mean an embargo from allied oil will drive Japan towards securing their own source of oil
  • Historical Limitations to how much USA can fortify the Philippines and Pacific islands without public opinion calling it wasteful and unnecessarily provocative.
  • Historical Limitations to how many divisions USA can pull from defense of continental US Cities leaving USA empty and undefended to defend Pacific islands or colonies of little value.
  • Logistics mean it doesn't make alot of sense for Japan to attempt to invade Oahu, but that they instead can invade 10 times more divisions towards other targets 10 times closer to their home bases

These are just a few examples. There are alot of game mechanics that could promote a more historical flow and events more similar to historical ones in a flexible and dynamic way instead of hardcoded/scripted to happen identical to history.
 
Saying that it's a disaster there is no Pearl harbor in HoI4 is a bit like saying that it's a disaster there is no guarantee the German 6:th army will be encircled and destroyer in Stalingrad in HoI4.

Instead of complaining about lack of hardcoded events, NFs or decisions, we should be asking for game mechanics that make these situations more likely and effective moves if a historical path is followed. Where are the mechanics that have it make sense for USA to base their fleet at Pearl harbor as a deterrent or Political statement, that prevents USA from fortifying the entire Pacific and that makes an historical surprise attack a logical path for Japan to take?

Mechanics like:
  • Airplanes on the ground can be destroyed in large numbers when a nation at peace is surprise attacked by Axis aggressors ( Like in Soviet or for USA )
  • Port/Airbase Strikes by Carriers are prepared like invasions ( hit hard but once, instead of small attacks several times per day ) and can be launched as an opening move when declaring war
  • Such missions are coordinated automatically by the game to all hit their targets at the same time, or to progress to a "launch point" close to the target and wait for Declaration of War
  • It is possible to use decryption, espionage or scouting by air/submarines to locate enemy warships at port so you know where to target portstrike missions
  • Political and Strategic reasons that cause USA to base lots of warships in their Main Pacific base at Oahu
  • Fuel situation in Japan that mean an embargo from allied oil will drive Japan towards securing their own source of oil
  • Historical Limitations to how much USA can fortify the Philippines and Pacific islands without public opinion calling it wasteful and unnecessarily provocative.
  • Historical Limitations to how many divisions USA can pull from defense of continental US Cities leaving USA empty and undefended to defend Pacific islands or colonies of little value.
  • Logistics mean it doesn't make alot of sense for Japan to attempt to invade Oahu, but that they instead can invade 10 times more divisions towards other targets 10 times closer to their home bases

These are just a few examples. There are alot of game mechanics that could promote a more historical flow and events more similar to historical ones in a flexible and dynamic way instead of hardcoded/scripted to happen identical to history.

Good ideas.

May I also add that opting to launch surprise attacks on "core territories" or even just the warships/planes in US-controlled territories instead of the usual justification-then-declare-war mechanic will not only further increase war support, but would allow the defender a more delayed time to capitulate. (Like how the USA is so pissed at Japan that they settled with nothing less than absolute victory per FDR's speech)

I honestly don't know how these mechanics could be implemented but these will most certainly do.

EDIT: Now that I think about it, such mechanics would only work if there's a revamp on peace negotiations as well. Like how the war was started would definitely affect peace terms.
 
About Pearl Harbor: I would like a general surprise attack mechanic or a specific one for Japan that could simulate this. I think it would not disrupte the gameplay too much and could give Japan a 3month headstart to conquer South Asia to get a breathing space before US come knocking... or something like that. I think there is room for a 'Pearl Harbor-like' mechanic in a sandbox fashion without being limiting.
 
Ok look ALL I’M SAYING is I want SOMETHING like Pearl Harbor that at least most of the time happens at Pearl Harbor as whenever I play this game and I try to go Historical whenever something goes out of place if I am disgracing EVERY SOLDER THAT DIED AND LIVED FOR MY FREEDOM and that is UNACCEPTABLE to me.

All of my family that was male and around during WWII served whether it be the Beaches of Normandy or the Sands of Iwo Jima and all of them have memories that haunted them their whole lives so my philosophy is that anyone who disrespects the people who gave them their freedom deserve whatever comes their way BUT I often take much things as disrespect so I often attack people when I really shouldn’t.
You seem very angry about things you had nothing to do with. Maybe practice mindfulness?
 
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.
The posts I was talking about are now deleted but you're right HoI4 is almost consistently being most played by the Paradox fanbase and it is the one with the longest wait times between expansions. I saw 4-8 posts saying the order in which they replied and/or "release date when?" so I expressed my disappointment. I was hoping to read the many insightful comments and discussion that follow these dev diaries especially with ones with such care put into them such as this one.

Megacorp released in a shockingly broken state and both Synthetic Dawn and Apocalypse had broken achievements along with a plethora of bugs. The fact the team is taking as long as they need to finish this is fine with me. Megacorp is still broken end game to the point I have to use the test branch to even finish my game, even then I still got a hard crash to desktop for an unkown reason.

On another note EU4 released a lacklustre immersion pack which lead many fans being disappointed and DDRJake admitting as much in a dev diary after the new year.