Prepare to use your intelligence to win the war. The latest expansion for Paradox Development Studios’ World War 2 title focuses on all things espionage and has a revamp for several nations. Prospective partisans and all other players will also be getting a large patch with new free features.

You could be excused for thinking that the latest expansion for Hearts of Iron IV is all about the plucky resistance fighters and partisans that fought various occupying forces and oppressive governments during the Second World War. While they certainly feature in new mechanics, there they’re not the main attraction of this sizeable expansion. Instead, La Résistance’s major features can be split into two broad camps: the introduction of espionage and skullduggery and unique focus trees and content for Iberian nations and France.

The new espionage system adds a new layer of strategy to the game. Its fundamentals are simple: spend resources to establish an agency, recruit agents and then send them off in missions to further your aims. It’s a system that’s rather intuitive and offers a degree of flexibility in how you choose to grow your spy agency. In the various games that I played I found that it didn’t require much micromanagement and that I was able to approach warfare in slightly different ways each time around thanks to the help of my agents.

The types of missions available are plentiful and, honestly, slightly overwhelming when it comes to actually deciding what I wanted to go for. This is in part because of the very long time it takes to infiltrate other countries, crack their codes or plan some of the more useful operations like winning over potential quislings so that future occupations are smoother. For typical aggressor nations, like Germany, it’s simply not worth the bother to send your two or so agents to France in the early years to destabilize them. By the time that you’re able to do anything useful in these infiltrated countries, you’re likely already on the verge of overwhelming them militarily anyways. The spy game plays best for long-term calculations, against foes who you have the luxury of time to undermine thoroughly.

It was only when I played as the USSR and another game as the UK that I got a greater appreciation for the espionage system. With the Soviets I was able to dupe the Japanese with fake intelligence about my armies, spawning ghost divisions that I could move around the map. These presumably would fool the enemy as they would think them real resistance and thus have a deterrent effect in the Far Eastern theater. The British were even more fun in that regard with my large espionage net launching commando raids and supporting partisans in Yugoslavia and elsewhere, pulling valuable Axis forces from front lines in order to deal with these burgeoning threats.

I’m not completely sold on the balance of the espionage system, especially as nation with few allies have a much smaller number of available agents to use in the field. As operations take a long time to execute, you might find yourself as, say, Italy or Japan only pulling off any those of major significant once or twice in a game. Agents might take a little too long to gain traits or gain experience as well as I only recall one or two promotions in all of the half a dozen or so quick games I played. Still, the balance feels alright for enough that the time that this is only a minor gripe. Most importantly, if players want to ignore the whole espionage system they can just invest in passive defenses and continue to crush their enemies in more traditional fashion.

The other big chunk of content that’s come along with La Résistance are the new focus trees. Spain’s civil war features prominently and I have to say that the balance of the conflict feels about right now. Foreign powers can intervene, sure, but for the most part both Republicans and Nationalists put up a stiff fight and the winner can be a close call. These focus trees also allow for alternate history to varying degrees of plausibility. Monarchies being restored in Portugal and elsewhere and various Spanish factions can opt to fight their former allies int he middle of the civil war. They’re well thought out I found and seeing civil wars within civil wars are chaotically lovely touch. Yes, some things that France or Portugal can do with their new trees is outright outlandish but there’s plenty to appreciate for both fans of historical detail and those who like alternate history.

Besides the new focus tree and espionage content, La Résistance also adds to the array of equipment that can be produced. Armored cars are a new cheap way for nations to add some toughness to their troops while scout planes can grant players with intelligence by overflying enemy territory. They’re useful but non-essential. Nice to build but won’t alter your fundamental strategy. When compared to the rest of the content of the expansion they're little more than nice miscellanea that you also get with the big changes.

I think that the individual pieces of the expansion are solid and interesting but they’re not necessarily a coherent whole. I know some players prefer flavor in the form of events and focus trees while others might enjoy the espionage system better. As neither one really feeds into the other it’s fair to say that whether or not you’ll enjoy La Résistance will depend heavily if happen to be interested in both disparate halves of the expansion. If you’re only interested in the espionage portion of it, or the Iberian nations, this might not be worth picking up straight away.

As is tradition with major expansions for PDS games, a very large patch has also been made available for all players. This one is codenamed “Husky” and there’s quite a bit of new content aside from the usual bug fixes. The new compliance and resistance system is part of the patch and adds a degree of granularity to how you treat occupied territory. Garrisons are mostly off-map and become more of a worry to balance properly as you occupy more of your opponent’s land. Quite a few quality-of-life changes also made it in, including UI overhauls for certain menus that I found made the game easier to understand. It’s well worth checking out the full change log.

I also noted possible AI improvements, at least when it came to naval invasions. When fighting the Japanese as the USSR I found that they were more than willing to use their naval superiority to try to defeat me. At times they would land divisions behind my defensive lines and attempt to capture ports to keep their troops supplied. I witnessed the AI build plausible bridgeheads in other theaters so that sort of behavior ought to make for more interesting gameplay.

All in all, it’s been fun to get back into HoI IV with this new patch and expansion. There’s plenty to like if you give it a chance. It’s my hope that Paradox will apply the same level of diligence when it comes to approaching other underwhelming areas of the game in the future, such as the Eastern Front. The base game is already a fairly solid experience that’s been improved a lot since the game’s launch four years ago.

You can get a copy of Hearts of Iron IV: La Resistance from Humble Store, Paradox’s Webshop or Steam.