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HOI4 Dev Diary - Amphibious Vehicles and Research

Hi everyone! Another wednesday means its diary time! Today we will be talking about some quite big balance changes to tech as well as some new... watery toys :)

Amphibious Armored Vehicles

With Man the Guns we are adding two new classes of vehicles. Amphibious Tractors (AMTRACs) and Amphibious Tanks. AMTRACs were built in large quantities and used both in the Pacific by US Marines with good success as well as in Europe during major river crossings such as the Allied crossing of the Rhine. An AMTRAC is a amphibious tracked vehicle that offers soldiers protection, and depending on model, firepower when conducting landings.

upload_2018-10-3_14-57-28.png


For heavier armor and firepower, amphibious tanks were developed. The allies used quite a lot of the Duplex Drive Shermans during D-Day. The idea was that the tanks would swim to the beach, then drive on to assault the German fortifications. The Sherman DD itself had some design problems, as it was designed for only 30cm high waves… which aren't exactly rare at sea. Many of them were also unloaded from their landing ships much too far out and sunk in the waves. Some beaches had good results, but for example Omaha beach was a disaster where most of them were lost. The Germans also planned for tanks for Operation Sealion, but experimented with snorkels and driving along the bottom instead. These were instead used during Barbarossa. The Japanese went more in the direction of attachable “flotation parts” with the Ka-Mi and Ka-chi tanks, making them look like tiny little warships. They never got the same large scale testings as the American tanks, but to me at least, seem to have been a more reasonable technical solution.

upload_2018-10-3_14-57-55.png



These things combined means that you can design divisions to punch through heavily defended landing sites. Quite useful late game! These divisions are also great for when the enemy has fortified across a large river. On the flip side they are quite expensive to make, less fuel efficient and a little slower for what you get so you should have some plan for them before investing. Amphibious vehicle battalions also use your special forces limit, just like marines.

upload_2018-10-3_15-0-30.png



Man the Guns comes with 10 unique 3d models for the amphibious tanks:
mtg_amphibious_eng_sov.png

mtg_amphibious_ger.png

mtg_amphibious_usa_generic.png

mtg_amphibious_jap.png


The mechanized infantry AMTRACs can be found in the Infantry tech tab while the Amphibious tanks are a branch of light tanks (the tier 2 amphibious tanks are close in stats to the 1939 medium tanks):

upload_2018-10-3_15-4-56.png

upload_2018-10-3_15-5-32.png


Research Changes
We are changing up some things when it comes to technologies as well. Because we have been steadily adding more, and are adding a bunch more with Man the Guns, we will be adjusting the base research speed to be faster. Probably something like +10%, but we haven’t locked that down yet.

We are also changing how the formula works for calculating how long it takes to research things. Instead of a research bonus lowering the cost of the research, bonuses now affect the speed of research. This means that an old -50% cost modifier is roughly the same as a +100% speed modifier now. I say roughly because speed modifiers stack a lot better and in less odd ways when there are many of them. This essentially means that you can no longer get instant techs by stacking various modifiers, just really fast research.

We have also changed how ahead of time works and the Ahead of Time Bonuses from focuses etc. no longer give you a percentage off, but a number of years off. This is important because it makes certain tech rush strategies where you simply bypass much of the tree by chaining ahead of time bonuses not work. We feel that these things will make things play a lot saner, and stop ahead of time researching to be banned in some MP groups ;)
upload_2018-10-3_15-33-50.png


The other change we are doing is to allow certain techs to get a bonus from XP. All doctrines as well as certain modules like torpedoes get a research boost when spending XP on them. This does two things for us: On the one hand we are not happy that one of your research slots is basically always locked to land doctrine research, and also the fact that we don’t really want nations to have maxed out their doctrines by the start of the war. So doctrines now get a bit slower to research, but by spending XP (benefitting the nations we want to have an edge here, like the axis) you will be researching faster than before. The other thing is to model certain stuff that were notoriously hard to get working right, like torpedoes, which for some periods of time had something like a majority failing to actually detonate when hitting a target. We want nations who get to see action here or dedicate training time on it to have a bit more of an edge.
upload_2018-10-3_15-34-39.png


That’s it for this time! Do not miss that we are starting streaming of Man the Guns gameplay today, so tune in to see the new USA tree at 16:00 CET at https://www.twitch.tv/paradoxinteractive
 
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@podcat , how will equipment conversion work? Will we be able to convert light tanks to amphibious tanks or will it just be a totally new thing?
 
@Conscript292

She won't need to... if you build a hanger on her.
 
Nice ideas here, although unsurprisingly I can't quite grasp how the new research balancing will play out. Time will tell. Please be careful how you apply XP to research bonuses, because experience mining is quite easy in this game. That would produce instant breakthroughs via another route.

And it would be nice if the reliability rating of those amphibious tanks were set at an appropriately low level!

Great points. XP comes quickly once the war gets going. This might make people forgo making variants of tier-II equipment and save their XP to rush tier-III. Balance is going to be tricky.
 
Wait, so when it comes to DDs and the other AMTRACs will that effect how they can do things like amphibious invasions? I'm not seeing much use into any of this aside from river crossings which CAN HINDER forces, but it won't STOP them (At least for my case) alongside any other small tid bits
 
Could the use of research bonuses be changed so we can choose when to use a bonus. If we have an armoured research bonus avaliable we could choose not to use it on a light tank research we start, but save it for when our medium tank research comes up.
 
"Insanity is doing the same thing over and over again expecting different result." Albert Einstein
Well now hopefuly the ai will be less insane when trying to land 50 divisions in northern France
 
Nice, glad to see the game getting some new equipment :)
 
why aren't amphibious tanks just a new kind of variant? Wouldn't that make more sense, knowing how duplex drives were mostly modified Sherman tanks. Making amphibious tanks have they're own branch seems odd to me.
 
why aren't amphibious tanks just a new kind of variant? Wouldn't that make more sense, knowing how duplex drives were mostly modified Sherman tanks. Making amphibious tanks have they're own branch seems odd to me.
The knowledge needed to "invent" this kind of thing is much greater than what it takes to put a different type of armament on a chassis....
 
Cheers for the DD Podcat, amphibious goodness :D. Love the new amphibious techs and the way they work with special forces battalions, and the cool models as well :). XP helping tech progression also looks like a good change that could add some depth and variation in the tech side of things.

Also, love the pics in the DD :cool:. Here's another, because every thread needs more naval-related pics (and it's one of my favourite pics relating to Amtracs, very atmospheric/foreboding) :D

Amtrac's and Tennessee small.jpg



we considered it, but then we kinda wanted to redo everything about invasions... and that was too big to fit into MTG. So hey maybe sometime in the future. I've never been 100% happy with the transport techs. it kinda hard-locks something that should be a production issue. but its nice and easy :)

It would be seven shades of awesome if there could be some depth added to the transport/invasion side of things - developing the amphibious landing ships (LSTs/LCTs/LCAs/LCVPs/etc,) and then building enough was a big thing (iirc - which in my current state is by no means guaranteed - at one point it was the highest priority for US naval construction).

It looks that we can research Warship Fire Control in the electronic research page. It looks like HMS Warspite can out range Italian battle ships after all.;)View attachment 408237

Strictly speaking, Warspite was a little lucky on the day, and the 320mm Italian guns outranged the Warspite's 381mm guns by a little bit (sources vary, from about half a km to 1-2km) - but I've got no idea which fire control computer was better at those distances :). The Italians were very heavily into long-range gunfire with their BBs, often at the expense of other things.
 
You could also make naval invasions more realistic simply by massively reducing the # of divisions supported by each transport tech.

Mix this with more transport tech's in general. with rather than just 3 transport techs it should be like, 6. so you start as absolutely horrid, and as you progress you can eventually D-day style at max tech level.

@podcat - something I could suggest for you all. to make Transport tech bigger, so you need to invest more to your transport and landing development when you go for amphibious operations so not all naval invasions turn to D-Day or Bust.
 
The Japanese went more in the direction of attachable “flotation parts” with the Ka-Mi and Ka-chi tanks, making them look like tiny little warships. They never got the same large scale testings as the American tanks, but to me at least, seem to have been a more reasonable technical solution.

View attachment 408178

From what I understand, the Ka-Mi was actually amphibious without the extra flotation pontoons. It was merely limited to calm waters like slow-running rivers or the inside of a reef or similar without them. The US' preliminary reports on it in 1944 believed the pontoons to be strictly necessary for it to float at all, but the IJN's own documentation and post-war sources don't seem to corraborate this.
 
Hi everyone! Another wednesday means its diary time! Today we will be talking about some quite big balance changes to tech as well as some new... watery toys :)

Amphibious Armored Vehicles

With Man the Guns we are adding two new classes of vehicles. Amphibious Tractors (AMTRACs) and Amphibious Tanks. AMTRACs were built in large quantities and used both in the Pacific by US Marines with good success as well as in Europe during major river crossings such as the Allied crossing of the Rhine. An AMTRAC is a amphibious tracked vehicle that offers soldiers protection, and depending on model, firepower when conducting landings.

View attachment 408177

For heavier armor and firepower, amphibious tanks were developed. The allies used quite a lot of the Duplex Drive Shermans during D-Day. The idea was that the tanks would swim to the beach, then drive on to assault the German fortifications. The Sherman DD itself had some design problems, as it was designed for only 30cm high waves… which aren't exactly rare at sea. Many of them were also unloaded from their landing ships much too far out and sunk in the waves. Some beaches had good results, but for example Omaha beach was a disaster where most of them were lost. The Germans also planned for tanks for Operation Sealion, but experimented with snorkels and driving along the bottom instead. These were instead used during Barbarossa. The Japanese went more in the direction of attachable “flotation parts” with the Ka-Mi and Ka-chi tanks, making them look like tiny little warships. They never got the same large scale testings as the American tanks, but to me at least, seem to have been a more reasonable technical solution.

View attachment 408178


These things combined means that you can design divisions to punch through heavily defended landing sites. Quite useful late game! These divisions are also great for when the enemy has fortified across a large river. On the flip side they are quite expensive to make, less fuel efficient and a little slower for what you get so you should have some plan for them before investing. Amphibious vehicle battalions also use your special forces limit, just like marines.

View attachment 408179


Man the Guns comes with 10 unique 3d models for the amphibious tanks:
View attachment 408182
View attachment 408183
View attachment 408184
View attachment 408185

The mechanized infantry AMTRACs can be found in the Infantry tech tab while the Amphibious tanks are a branch of light tanks (the tier 2 amphibious tanks are close in stats to the 1939 medium tanks):

View attachment 408180
View attachment 408181

Research Changes
We are changing up some things when it comes to technologies as well. Because we have been steadily adding more, and are adding a bunch more with Man the Guns, we will be adjusting the base research speed to be faster. Probably something like +10%, but we haven’t locked that down yet.

We are also changing how the formula works for calculating how long it takes to research things. Instead of a research bonus lowering the cost of the research, bonuses now affect the speed of research. This means that an old -50% cost modifier is roughly the same as a +100% speed modifier now. I say roughly because speed modifiers stack a lot better and in less odd ways when there are many of them. This essentially means that you can no longer get instant techs by stacking various modifiers, just really fast research.

We have also changed how ahead of time works and the Ahead of Time Bonuses from focuses etc. no longer give you a percentage off, but a number of years off. This is important because it makes certain tech rush strategies where you simply bypass much of the tree by chaining ahead of time bonuses not work. We feel that these things will make things play a lot saner, and stop ahead of time researching to be banned in some MP groups ;)
View attachment 408187

The other change we are doing is to allow certain techs to get a bonus from XP. All doctrines as well as certain modules like torpedoes get a research boost when spending XP on them. This does two things for us: On the one hand we are not happy that one of your research slots is basically always locked to land doctrine research, and also the fact that we don’t really want nations to have maxed out their doctrines by the start of the war. So doctrines now get a bit slower to research, but by spending XP (benefitting the nations we want to have an edge here, like the axis) you will be researching faster than before. The other thing is to model certain stuff that were notoriously hard to get working right, like torpedoes, which for some periods of time had something like a majority failing to actually detonate when hitting a target. We want nations who get to see action here or dedicate training time on it to have a bit more of an edge.
View attachment 408188

That’s it for this time! Do not miss that we are starting streaming of Man the Guns gameplay today, so tune in to see the new USA tree at 16:00 CET at https://www.twitch.tv/paradoxinteractive


The Dev Diary again is fantastic... outdone yourselves guys and girls back there, i cant wait to discover more and more about it... it looks like its gonna be a long long year after Man the Guns DLC is out that we will have to test the new goodies and toys you will get for us! Finally my troops can land safely in North Africa Italy and back in Europe to drive the nazis and commies out of Europe... Long live the Paradox Interactive!
 
Strictly speaking, Warspite was a little lucky on the day, and the 320mm Italian guns outranged the Warspite's 381mm guns by a little bit (sources vary, from about half a km to 1-2km) - but I've got no idea which fire control computer was better at those distances :). The Italians were very heavily into long-range gunfire with their BBs, often at the expense of other things.

Ive read many simlar debates on theoretical Iowa Vs Yamato battles. Yamato could easily outrange the Iowa's and hit harder, but the Iowas were far more accurate and better maneuverability.

So at 15 miles the Iowa could land most shots while the Yamato would be struggling to land any. So as long as the Iwoa's could stay at maximum range of it's guns they could have chance.

***If I remember the numbers correctly, the Yamato could fire 20-21 miles out, but was only accurate up to 12 miles. The Iowas could fire up 18 miles out on a good day, but were highly accurate up to 15 miles (possibly still better then the Yamato's at 12). So there's a 3 mile buffer zone where the Iowa's could theoretically maintain a stand off position to hammer the Yamato and have a good chance of not getting hit, or at least not getting hit critically.
 
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I'm not aware that any of them had an amphibious tank project. Two of them are landlocked nations that don't even have a navy!
@podcat

I can tell you that the Romanian Navy was well in existence back in WWII but was mostly a coastal and river fleet since no real navies are around the black sea region :)