Accessibility. The game should not scare a new player. New target audience outside fans of previous games is people who enjoy CK2 and EU4, and are interested in WW2, it should not be harder to get into than those games necessarily.

If a feature doesn't show in an interface its not a feature

The effort spent on a feature should be proportional to the amount of player interaction it has. No interaction and its not a feature.

a feature should have a clear reinforcement loop in its feedback. eg: "see problem"->"do action to fix problem"->"see problem solved"

No AI control cop-outs. There shouldn't be any checkboxes saying "plz automate this". Then we would rather remove the feature.

Less complexity for complexity’s sake features while delivering the same or more flavor than before.

less micro, more macro decisions, but avoid very very long decisions such as stockpiling that player will always fail on the first time.

Prefer planning decisions rather than last-minute decisions. There are many things to keep track of in HOI and sometimes there is a lot of free time and sometimes there is a ton of stuff going on, so if we can make some of those decisions while its calm you get a much smoother workload for the player. Click to expand...

A nation level planning tool where all armies were part of the same plan, and the player controller synchronization points (say the northern army group would come in at point X when the southern group had reached a certain point). This worked well… until we added an AI. At this point we realized that the plans needed to be able to adjust to changing circumstances a lot better. At this point plans were more like overlays also and did not follow units or change when enemies took provinces. We changed the system to adjust based on fronts and province changing. At this point you drew arrows rather than fronts, which felt great… but didnt work so well during unpaused play either, because you also needed to control the width of the fronts. The final iteration before launch was changing it so that you drew fronts rather than arrows. It felt a bit worse, but gave a lot better control.

Hi everyone! On the 6th of June 3 years ago we released a little game called Hearts of Iron IV. Now obviously the 6th is tomorrow, but of course this is sweden’s national day, as well as being earmarked for recovery after the paradox summer party that’s happening tonight. So you get to enjoy my anniversary diary one day earlyBut, before we get into all of that, first let’s talk about yesterday’s releases!Yesterday we released the 1.7 ‘Hydra’ free update which brought the game to 64-bit as well as improvements to AI, front systems and convoys . See here for full patchlog . Together with this update we also release a Radio pack filled with new music as well as the Axis Armor Pack for your tanking pleasureWe hope these prove popular because we have lots of ideas for future ones we would like to do if it goes wellMost of the design was written during the summer of 2013 with me chilling out to documentaries and sipping beer in the sun. Back then we were a lot smaller and the whole original design doc is actually smaller than most expansion docs are nowActual development ramped up late 2013 and we actually showed off the game to journalists super early in Januari pdxcon 2014 for some initial feedback. At this point there was no ai, and 90% of mechanics did not do anything. My most vivid memory of it is explaining to Angry Joe how you could nuke the world as Hitler ;D That and Justin Bieber crashing a ferrari in the nearby neighborhood in miami…I had a couple of goals with HOI4: I wanted a game that would be easier to get into for new players. I wanted a more high level experience focusing less on micromanagement of battle and more on the buildup and planning aspects of WW2 (it’s not very sexy, but in my mind WW2 was won by logistical planning and war production, not heroics). I wanted to dial back some of the complexity of HOI3 and bring back some of the lightness & freedom of HOI2 for players - to let them develop and personalize their countries more. I wanted to ramp up country specific flavor and bring back things like tech teams to a degree. I also wanted to make the best platform for modders we had ever done, because I always felt a bit sad that HOI3 never really had the modding community that HOI2 did.A lot of these choices were based on experiences working on HOI3 and Vicky 2. Hearts of Iron III had focused very hard on the historical aspects, to a degree that it couldn't really handle small deviations and I wanted to make sure HOI4 could handle this as well as providing a historical experience.Johan dug this up, which is my first pitch for roughly how I wanted to balance the focus on the new game:Here was the first section guidelines for feature design I put down:I feel like we mostly lived up to the initial goals in the end and the game launched to very good reviews and sales as well as a ton of new players joining us and the community growing over time.We had 2 major struggles during development I would say and they together led to us having to delay the release quite a bit.One was the battleplanner & AI. We went through quite a bunch of iterations on this one. The goal was always a system that assisted the player and would still need the player to go in and adjust things (no playing itself!), but finding the right balance between hand holding and automation was very hard. So were the exact controls. It was tough to find a solution where you could adjust stuff without pausing, and where orders wouldn't override the player too much. On the other hand the system was absolutely crucial for us to give the player the high level experience we wanted and the fantasy of drawing up plans for their units. We also did not think players would accept going back to HOI2 level province counts, which would have been required if it was all manual. It went through several iterations:The other tricky system was focus trees. We wanted a system to guide new players to what to do, and also use this system to steer the AI. it was also supposed to act partially like a tutorial for the first 2 years. We ended up with a system called “national goals” that kinda acted a bit like the current decisions, but with some more map interaction. The big problem was that it could only really show stuff one step ahead and it was really hard to get an idea for where you could take a nation. As a beginner it also wasn't exactly clear how anchlussing Austria would lead to wargoals on Poland in the end. We ripped this out and replaced it with what you now know as Focus Trees, and some ideas were later brought back with Decisions in Waking the Tiger.I suspect anyone reading this knows how Paradox works. We keep support our games over long time both with free updates and paid DLC where we try to strive for a 50/50 balance. This gives us the unique opportunity to rework and improve systems after release, and to adjust and grow the game based on feedback. Some of this feedback also comes from telemetry data which is invaluable because the HOI community is pretty much split right down the middle between historical gamers and ahistorical games, and of course also with a hardcore group of competitive MP players. So we gotto make sure we get the right picture and not just who is loudestLet’s go through all the expansions up to now!TFV was our first expansion and we were still putting in a lot of work on bug fixing and balancing at this point so a lot of the free dev work went into that. The biggest feature it gave us was the new subject systems with autonomy levels, something we have been building on ever since. It fleshed out all the british subjects with focus trees, but didn’t go super deep into alt-history quite yet even though we were playing with it.For death and dishonor we focused on european minors, primarily on the axis side. This is when I think we really started to steer the game towards alt-history. We decided this DLC would be our test and we did pretty out-there stuff like reforming Austria-Hungary. Turns out people really liked these kind of focus trees and we decided from now on to focus on 50% history paths and 50% alt-history going forward. DoD also saw us do our first big revamp of a core mechanic as we changed up air warfare quite a bit.For Waking the Tiger we wanted to go big (perhaps too big). We wanted to flesh out armies and commanders so introduced more traits and the chain of command. We made new focus trees for most of asia and really focused on the China vs Japan conflict. It felt like a bit of a gamble at the time, because it’s simply less known here in the west than the rest of WW2.Here we also started to revamp old core focus trees and doubled down on alt-history with paths for the Kaiser coming back to power in Germany (you guys loved this one!)For MTG the time had come for tackling naval warfare. We wanted this to be the first HOI game with actually decent sub warfare (a tough nut to crack!) as well as other engagements. It was a very ambitious project. Probably the toughest I have done, but I am proud and happy of what we accomplished. In hindsight we should have probably added a naval tutorial though. The original HOI4 never had one, so we didn’t really factor in making a fully new one, but naval warfare has now become just as important as the other two branches of war. On the nation side we revamped USA and UK and did a bit of an experiment with both Mexico and the Netherlands. Mexico because it didn’t really join, and Netherlands because it was defeated early, and was also quite small. I think the way we dealt with both worked out very well actually and shows that if a focus tree is good enough even a smaller power can be equally fun to play.We are now starting development on the next expansion, which is still secret...I asked on twitter if people had any questions on development, and (not) to my surprise most of it was asking about what is coming next (it’s still secret guys!). Here are a couple:It depends a bit on how you define the question. Technical capabilities? Do we factor in cost? Ease of production? I think the Panther is a really cool machine, but if you look at things from a strategic point of viewI think it's easy to say that the Soviet T-34 was the best tank. Technologically solid with sloped armor, mass producible and cost effective, and with a flexible chassi. Do feel free to argue with me in the comments though ;PActually, the majority do not play historically. Its fairly split along the middle and for several nations the alt-history paths are more popular than the historical. I think the great thing about HOI4’s design is that it can accommodate both playstyles, while say HOI3 only handled historical games.As for MP, we do spend more effort on it than the player counts would warrant. There is a small percent of players that play at this level, but balance issues etc that they find are important both for single and multiplayer. Of course we can not always change things right away as the AI will need to also cope with the changes.Officers helped define nations a bit in HOI3. For those things we mostly have it covered with unique national spirits etc though. However, I do think they could exist in some form in HOI4 one day but it would definitely be another way. I was never really happy with how leadership worked in HOI3 and the tradeoffs you had to make were mostly no-brainers.We have discussed the idea in the past actually. Its a cool idea. I feel like you might need to have alt-history ones as well to make sure it fits in as things change?We’ve had a pretty steady pace to make sure we update the original trees over time. I think its a pretty safe bet to assume at least one gets updated in each major expansion. It has a lot to do with what other countries fit in with it and what the theme is rather than their importance at this point though.I am pretty happy with manpower laws for modelling this, so no current plans.Definitely convinced to try them out. Both add a lot to the complexity of the game, but I think that its ok to move the boundaries a bit after the game has been out for a while and people have gotten comfortable. The way we solved the issues of fuel compared to HOI3, where it was kinda a solvable problem (so you just stockpile once and don't worry anymore), is worked around by having a limited stockpile you had to invest in to build up, and since its the only resource that behaves this way it does not totally change the need for constant resource access.Tough one. The last expansion always feel the best, so Man the Guns I guess with Death or Dishonor second ;D I am weird when it comes to features and usually have the most fun when I work on AI behind the scenes. If I gotto name one thing though it was probably Decisions from Waking the Tiger. I really felt like we lifted the concept up one more step compared to how we had done it in previous games. They are really cool and flexible now for doing all sorts of gameplay and reinforcement of focus trees.You can collapse army groups if things get too much, but who knows, maybe? I don’t see us doing it for UI, but more for being able to place corp level assets on map or the like.I’m not sure ya’ll are ready for how overpowered it would be >:-DDefinitely AI and battleplans. With performance as a second thing. The combination of realtime and such high complexity, and also being expected to be competitive 1-1 vs a player is a tough nut to crack. With most of the other Paradox games we balance vs the player by having AI gang up on them, but in HOI4 that's not really a thing because of the historical situation so we really need to focus on having the ai fight ok in a more fair situation. We probably spend about a month on tweaking AI balance on each expansion.I think it ended up pretty cool! Some stuff ended up a little too complex compared to the initial intent though. I think doing it for Air makes a lot of sense as the plane type classifications we use feel a bit weird for modelling certain nations. Potentially for tanks also, although I think that it would need to be a bit simpler here.I went over some of this in the above 3 year development section. Basically I think its a natural progression if you want to support alt history and have nations who didn't join the war do so. HOi4 has always had two halves. Preparing and maneuvering for war and actually fighting the war.If you mean different cultures, no. It's a conscious choice. WW2 is pretty recent and can be a touchy subject without calling out specific population groups. If we are talking about other stuff then yeah probably eventuallyProbably Daniel? He has something like 10,000h while I am just under 6000h.Naval warfare. It was in the least iterated state and the amount of balance and iteration was very heavy.The only game I could see benefit from a globe would be a cold war game honestly (for accurate missile distances). Globes have a lot of downsides, like not being able to see half the world etc. Maybe something like Imperator’s simulated half-globe camera though, I quite like that one after getting used to it.It’s a secret still!Today we will also have an anniversary stream special with me and Daniel at 15:00 Stockholm time. I have managed to dig up an old pre-release version of the game for us, and we will be looking at that as well as talk about the last 3 years of development. Don’t miss it!See you all next week!