Few grand strategy games have been as genre-defining and long-lasting as Hearts of Iron 4. This classic World War 1 wargame is basically the go-to option if you're interested in this particular era, but the funny thing is that, over the years, it's been substantially upgraded to basically feature parity with any other cutting-edge grand strategy released in the past few years.

The kicker, of course, is that not all of these upgrades are free, and are instead bundled in as part of paid expansion packs/DLCs. The publisher and developer, Paradox Interactive, has made an impressive business out of platform-type game development, and Hearts of Iron 4 is one of its crowning jewels. What this means in practice is that you're going to want to upgrade your base experience in some way, shape, or form. That's where this guide comes into the picture!

Top 5 Must-Have DLCs for Hearts of Iron 4

Hearts of Iron 4 has got no less than 12 standalone expansion packs as of May 2025. That's just the big, meaningful DLCs, mind, as we're not counting graphics packs or soundtrack bundles into this particular equation. Purchasing all of these expansions is no mean feat, and the odds are good you're going to want to specifically target certain experiences instead.

Knowing which DLCs to purchase is a huge deal, with that in mind, and that's why this handy little list is going to be extremely useful for HoI4 newcomers. We've picked out exactly five of the very best Hearts of Iron 4 expansion packs to add to your experience as soon as possible. Heck, if you're particularly keen, we recommend you check out the full roster of HoI4 content right here at 2Game: we often stock deep discounts for these products, and bookmarking this link is the best way for you to stay on top of that!

With that all out of the way, let's finally take a look at Hearts of Iron 4's finest expansion packs:

#5: La Résistance

La Résistance is notable specifically because it's a massive expansion to Hearts of Iron 4's espionage and occupation mechanics. What you're getting here is basically a total rework of intelligence and resistance progression systems, with a lean towards spy, commando, and guerilla-style units and combat. In comparison, HoI4's baseline espionage mechanics are extremely simplistic and uninteresting, and we cannot recommend this DLC enough if you're into this type of gameplay.

#4: Arms Against Tyranny

With a focus on Nordic nations, Arms Against Tyranny adds substantial depth to each of these countries. The focus, as history buffs might've expected, is on customizable spec-op units that allow you to fine-tune your operational approach in a way the base Hearts of Iron 4 experience simply cannot accommodate. Crucially, Arms Against Tyranny also grants you weapon manufacturer and kit customization, which is extremely fun in its own right.

#3: Man The Guns

Man The Guns adds some much-needed nuance and complexity to a variety of gameplay features and resources. It separates oil from fuel, for one, which then ties into the rather excellent Ship Designer functionality. Arguably the single most important feature found in this entire DLC, we'd say! Man The Guns also offers the option to run a government from exile, which is entirely missing from the base game, and adds more depth to several fan-favorite nations all at once.

#2: No Step Back

Focusing primarily on the broader Eastern Europe and Soviet cultures, No Step Back is a must-have for players even remotely interested in any of these nations. The Tank Designer is an obviously massive boon, but railway guns, armored trains, dedicated railroad positioning, and a variety of fancy new Focus Trees makes this DLC an excellent addition even if you're not into the eastern flank of the European continent.

#1: By Blood Alone

The final major "designer" type feature focused on aircraft comes as part of the By Blood Alone DLC. On that note, this expansion also massively upgrades the plane-type unit roster with a whopping 67 new aircraft to choose and customize from. Players can now also give out medals to units, opt to demilitarize areas, conduct peace talks, and even issue out embargoes, each of which is a hugely important non-combat wartime asset building upon other tools in your toolbox. By Blood Alone is a high-point for Hearts of Iron 4's DLC collection, and it comes highly recommended!

Iron alone is never enough.