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- Hearts of Iron IV
Steam 4x Fest!
Generals! We'll be launching an additional offensive to coincide with this Steam 4X Fest, so get involved, maybe grab something for yourself or a friend, and get back out there! This sale will run until August 18th 2025…
- Hearts of Iron IV
Developer Corner | Aerohydrodynamics
Hello everyone! It has been a while since the last dev corner, as many of us (including myself) went on vacations - but now I have returned, even if it has been quite hard to readjust my brain back to the work frequenci…
- Hearts of Iron IV
Merch Survey!
Generals! High Command has issued a survey in order to gauge your thoughts in future HOI Merchandise! Get involved with the Form below, and let us know your thoughts about them; Click the image above, or here, to fill o…
- Hearts of Iron IV
Dev Corner | Faction Dynamics Part 2
If you haven't seen the previous Dev Corner, make sure to check it out here. Reinventing Faction Dynamics Part 2 Generals! Welcome to another Developer Corner. Let’s start with a reminder, or clarification, so you have…
- Hearts of Iron IV
Dev Corner | Thermodynamics
If you missed the previous Dev Corner, make sure to check it out here. Briefing: Thermodynamics Author: Zwirbaum Hello everyone! It has been eight days since the last dev corner, which means it is time for another one.…
- Hearts of Iron IV
Steam Summer Sale!
Generals! The Steam Summer Sale has arrived, and the Quartermasters have facilitated more deals for our frontline troops, make sure to check them out before time is up! Pick out something for your collection, grab somet…
- Hearts of Iron IV
Dev Corner | Hydrodynamics
Last week's Dev Corner can be found here, but let's begin the next one! Briefing: Hydrodynamics Written by: Zwirbaum Hello everyone! Another week is upon us which means it is the time for another dev corner. Last week T…
- Hearts of Iron IV
War Effort | Patch 1.16.9
Generals! We return with new intel from Command, a new War Effort is now live with balance and gameplay tweaks, UI and performance changes and a bunch of bugfixes, make sure to read them all below; Balance Afghanistan -…
- Hearts of Iron IV
Dev Corner | Reinventing Faction Dynamics (Part 1)
Generals! Continuing from where we left off last week, we have another briefing from Command. Find a comfortable chair, settle in, and read on. Briefing: Reinventing Faction Dynamics (Part I) Written by: Wrongwraith Hey…
- Hearts of Iron IV
Hearts of Iron IV Anniversary week & Developer Corners!
Generals! Not only is our nine year anniversary happening today, but we've got a lot of content for you all to read through so make sure to continue reading. We've got Developer Corners starting up again, HOI4 Anniversa…
- Hearts of Iron IV
Operation Brainstorm | Prototype Vehicles Available Now!
Generals! Welcome to Operation Brainstorm - File .: 1.16.6 :. This is the release of the final part of Expansion Pass 1: Prototype Vehicles. All of these models were either blueprints or early prototypes that were creat…
- Hearts of Iron IV
Paradox Publisher Sale!
Generals! Following the announcement of Project Caesar Europa Universalis V, the Paradox Interactive Publisher Sale has begun with deals up to 70% off for Hearts of Iron! This sale runs from now until May 15th BASE GAME…
- Hearts of Iron IV
Revealing Project Caesar!
Generals! Paradox Interactive are proud to welcome another soldier on the frontlines: Europa Universalis V is now available for wishlisting. Almost five hundred years of history unfold before you in Europa Universalis V…
- Hearts of Iron IV
War Games Fest Reinforcements!
Generals! The Steam Wargames Fest is already upon us, though we are joining later than most we are reinforcing the front lines immediately with up to 70% off! Hold the line with some fantastic offers on DLCs, or perhaps…
- Hearts of Iron IV
Developer Diary | Prototype Vehicles Unit Pack
Generals! We have some good news! Prototype Vehicles are almost ready to roll out, so instead of releasing them in Q3 as initially announced, we will launch them in Q2! Yes, the Prototype vehicle pack will be dropping s…
- Hearts of Iron IV
Patch Notes & Developer Diary | Operation EAR
Hey! @AveeBee here to give you a rundown of what we’ve been up to recently. Since Graveyard of Empires released, we’ve been working hard to polish and refine the new content to make it more enjoyable. Some of this has t…

