History YMMV / HeartsOfIron

** A bug for ''IV'' that was patched: political focuses can be mutually exclusive, which meant that if you did one, the other was locked off (i.e., do Oppose Hitler, you lose the focuses that the fascist branch has). However, if you managed to bypass one of the two focuses, you could access both branches, which would allow you to do some very overpowered stuff[[note]]in particular, there was the aforementioned German focus tree - both political branches could be unlocked by being in a war, which would remilitarize the Rhineland, and let you bypass the focus - which made forming the European Union or Holy Roman Empire very easy, and also the Netherlands - could bypass "Curtail Colonial Autonomy" by annexing the Dutch East Indies; they could be released as a puppet again afterwards - which would allow them to both set up the Dutch East Indies for relocation after the Netherlands capitulated and do the Zurzeizee Works[[/note]].

*** A similar, but even more broken, bug involving the Imperial Federation: If one gave the states that make up the British Raj to Australia or New Zealand, the focus would core them - this might not seem broken until you realize how much manpower and factory spots are in the Raj, and that this would also give the player access to Burmese and Pakistani manpower[[note]]by default, the Raj has those lands as occupied[[/note]]. Again, unsurprisingly fixed in a patch, although similar to Yugoslavia, other cores aside from the ones the Dominions start with by default can be obtained[[note]]if New Zealand and South Africa form their formable nations, the UK cores them as well; if the player goes Monarchist or Fascist, they can have Canada core all of the United States, and lastly, a Fascist UK can form the European Union after forming the Federation[[/note]].

* MemeticMutation:

** In ''IV'', after both tank and airplane design mechanics have been changed, the best results are achieved not by increasing various values, but keeping them at such a level, they don't add additional resources to the production (which keeps the production itself cheaper, too). The sheer cost-efficiency of using just steel for tanks and aluminium for planes completely outweighs any gains they could have had slightly higher stats, bordering on weaponised BoringButPractical.

*** ''IV'' specific: 40 width infantry units, in 14:4 infantry:artillery ratio and engineers, recon and AA battalion support. As far as single player goes, this is all you really need to win against even the strongest Major Powers, and you don't need the navy or air force in majority of conflicts, while your infantry will simply gun down the planes by sheer presence. The basic production required for success in almost all land wars are only Infantry Equipment, Support Equipment, Artillery and small handful of AA guns.

** What if X won World War 1?[[note]]The original user of this meme is the large mod ''VideoGame/KaiserreichLegacyOfTheWeltkrieg'' with the subtitle [[Main/AlternateHistory "What if Germany won World War 1"]]. The popularity of ''Kaiserreich'' led to many derived mods (most of which never got past the conceptual stage) and thus derived memes, such as "What if Belgium won World War 1?", "What if Russia won World War 1?", and things like "What if nobody won World War 1?" (which eventually got its own mod called ''VideoGame/RedFlood'') or "What if ISIS won World War 1?". The mod ''VideoGame/FuhrerreichLegacyOfTheGreatWar'' is also a case of "What if the Allies won World War 1?", in a sense parodying the meme.[[/note]]

** Not only can [[https://en.wikipedia.org/wiki/Wojtek_(bear) Wojtek the Bear]][[note]]a Syrian brown bear who was adopted in 1942 by Polish soldiers while they were stationed in Iran, and was officially enlisted as a soldier in an artillery supply company. He notably took part in the Battle of Monte Cassino[[/note]] be promoted as a commander for Poland, but the ''No Step Back'' DLC adds him as ''one of the claimants for the throne of Poland''!
* TrollingCreator: A specific set of circumstances (some player influenced, some random) allow Victoria Louise to be crowned as Kaiserin of a restored UsefulNotes/ImperialGermany (and possibly the UsefulNotes/HolyRomanEmpire). Her regal title? Victoria III. The Paradox fanbase always hoped that the next game announced would be a sequel to ''[[VideoGame/VictoriaAnEmpireUnderTheSun Victoria II]], which happened in 2021.''.

** The gradual shift of tone in ''IV''. On release, the game kept to the dark, bleak tone of the series so far, further adding new mechanics to keep track of the dead, both soldiers and civilians, and making that important aspect of gameplay. Then [=DLCs=] started to focus on alternative history scenarios, requiring AlienSpacebats-tier events for them to happen, often making things look just silly even as millions of casulties keep piling up. The humour is definitely not everyone's cup of tea. The height of this is that ''No Step Back'' gave Poland the ability to make Wotjek, a [[https://en.wikipedia.org/wiki/Wojtek_(bear) real life Syrian bear]] who was inducted into the Polish army to haul artillery shells, into a potential leader of the entire country.
** To this very day there are people who consider the research system from the first game[[note]]Each technology requiring industrial capacity invested into it, thus being based on nothing but wealth of the nation measured in the size of its industry, meaning the more you conquered, the more simultaneous research you could afford[[/note]] to be the best in the series, as it didn't have any sort of arbitrary mechanics (tech teams, leadership or research slot number) attached and further motivated people to conquest. Of course, each following system from sequels has its own supporters and they generally don't get along well. It's nowhere near as volatile as discussions about logistics, but the research system is probably the most memorable thing from the original game and is still discussed to this day.

** One branch of Yugoslavia's focus tree has a hidden feature - said tree breaks Yugoslavia down into the various nations that were combined into it, with the last focus allowing the player to re-annex said member states, and if their puppets had any additional cores, Yugoslavia would gain those cores as well - this would also include Bulgaria and Hungary if the player had managed to puppet them[[note]]at it's fullest extent, a player could have parts of Czechoslovakia, Romania, Greece and Italy as core territories[[/note]]. However, a bug early on gave Yugoslavia cores on any land ''occupied'' by said puppets, meaning that if one, oh say, defeated Germany and gave all of Germany to Slovenia, they'd have cores on all of Germany. This was patched, although if things go certain ways, it can still be very broken[[note]]the ability to core Bulgaria and Hungary means that the player could also core Czechoslovakia and Austria from Hungary if it reformed the Austro-Hungarian Empire, and the rest of Romania, Greece, and Albania from Bulgaria if it unified the Balkans; and of course, Yugoslavia can also gain cores on a few Italian states[[/note]].

** Italy will never get a new focus tree[[note]]Despite various changes in the game since release and new focus trees for various countries along with reworks of existing ones, Italy is still stuck in its original, release-state tree. This even including the changes made with Spanish Civil War, and all the trees being adjusted... except for Italian one.[[/note]]. Likely on it's way to DiscreditedMeme after the announcement of ''By Blood Alone'', which featured a new focus tree for Italy.

*** They typically have very little impact on gameplay but major impact on performance as the AI will favour doing nothing but spamming units the entire time but never declaring war. El Salvador is a meme in the community for sitting on it's two tiny provinces and doing nothing but creating dozens of units.

** The random purges in ''No Step Back'' would be fine if it wasn't for a combination of the fact that a), the only way a general or admiral can avoid being purged is if they have Stalinist Loyalties (which can be annoying if you're going for a civil war to overthrow Stalin, as generals with said loyalties will side with Stalin when the war breaks out), and b), Stalin can even target generals who, historically, he did not purge (i.e., Georgy Zhukov, Konstantin Rokossovsky, Aleksandr Vasilevsky), even if you're playing the historical route. There's also the fact that it's entirely possible for the player to have the bad luck of having Stalin ''purge their entire roster of generals'', meaning that you have to waste command power to generate new ones - which wouldn't be so bad if it wasn't for the fact that the high command now requires command power in addition to political power. For that matter, if you go for the Right Opposition, you had better hope that he doesn't randomly purge Alexei Rykov or Nikolai Bukharin, because if he does, then a good chunk of that path is locked out[[note]]the Left Opposition can send it's leaders and advisors into exile, thus allowing them to avoid being purged[[/note]].

** ''By Blood Alone'' continued this trend - while Italy's rework was guaranteed, and Ethiopia had been predicted by some, the third nation in the pack was ''Switzerland'', which is famous for it's policy of absolute neutrality - many fans expected Austria or Albania to round out this trio, given that their role in the game on historical is not that different from Czechoslovakia, which did get a focus tree.

** Also in ''IV'', it is almost automatic for a player's initial steps in the research tab to select electronic mechanical engineering for the base bonus to research speed, and whatever is available under the industry menu for boosts to production efficiency, factory and dockyard output, and cons

** While this has been primarily ignored in earlier games, in recent years following the release of ''IV'', there has been growing controversy regarding Paradox's refusal to showcase World War II atrocities, specifically Nazi atrocities such as the Holocaust (especially since Stalin's 1936-1938 Great Purge ''is'' portrayed in the game, requires player input, and has actual consequences on gameplay instead of being a mere "informative trivia" event). Proponents of showcasing World War II atrocities argue that not showcasing them feeds into far-right viewpoints surrounding the Second World War that whitewash the crimes of the Axis powers in favor of showcasing [[DracoInLeatherPants their flashy war machines]] without context, and may potentially play a role in creating a pipeline to radicalization at a time of rising far-right sentiments worldwide. Detractors of the idea argue that it would be poorly executed and done tastelessly if pulled off and that showcasing Nazi atrocities won't actually weaken any potential far-right voices in the fandom, but would instead give them a chance to roleplay their genocidal fantasies. There is also the fact that from the first game through the third, there ''was'' an event for the Nanjing Massacre whenever Japan took over that specific province -- and to make it even weirder, said event did absolutely nothing, being just a piece of trivia informing about it, along with being the only war atrocity to be ever addressed in the game. It's missing in the fourth game.

*** In ''IV'', most single players don't bother researching surface ships and exclusively build submarines and some form of bomber capable of conducting naval strikes. One because these units are hilariously broken and two, they're simple to use, allowing players to ignore the surprisingly complex naval combat system.
** Also in ''IV'', it is almost automatic for a player's initial steps in the research tab to select electronic mechanical engineering for the base bonus to research speed, and whatever is available under the industry menu for boosts to production efficiency, factory and dockyard output, and construction speed, all of which pay immediate dividends that continue for the whole game. In any game where full scale war can be held off for at least a couple years, almost every technology or equipment research can be delayed until all industry items are brought up to date.
** There is the BoringButPractical unit template in each of those games. There are might be situational variations and highly specific scenarios where you might want to have something else, but they are so good in combat and so efficient to make, there really isn't much point to do anything else.
*** ''Darkest Hour'' specific: 1942 infantry with towed artillery and half-in-half of engineers and tank destroyers. Almost all nations can pull this and you really don't need much more. If it's early war, the 1936 infantry with artillery and engineers are all you will ever need, especially when fighting anywhere outside Western Europe. ''II'' made it even more boring, since all you ever needed was foot infantry with artillery, while engineers were far less important.
*** ''III'' specific: in vanilla and ''HPP'' mod, it's two infantry brigades, artillery and engineers. In fact, this one borders on GameBreaker, given the absurd potency. Later in the war and when facing majors, the 5th slot is usually taken by the cheapo AT artillery.
*** ''IV'' specific: 40 width infantry units, in 14:4 infantry:artillery ratio and engineers, recon and AA battalion support. As far as single player goes, this is all you really need to win against even the strongest Major Powers, and you don't need the navy or air force in majority of conflicts, while your infantry will simply gun down the planes by sheer presence. The basic production required for success in almost all land wars are only Infantry Equipment, Support Equipment, Artillery and small handful of AA guns.
** There are many players who only ever play a single nation. Germany is the most popular, as their role is the attacker, which is more fun than a defensive nation like France. As can be expected, there are players who only play in their own home country.
** In ''IV'', unless you are fighting an early war the default strategy for what to research is pushing Tier 2 Production, Industry, Construction, 2 Electronics + Radio and depending on what country you are and if you're doing a tech rush, going for quick Medium or Heavy Tanks or Fighters. The industry and research techs are vital for establishing your economy, and getting better tanks or fighters is vital for certain nations to have before the Axis start the war against Poland and the Allies in 1939, before the invasion of the Soviet Union usually in 1942, and before Japan takes on the United States.
** ''IV'' has an option to randomize which focus trees countries go down, which can lead to events like a Military Junta overthrowing Hitler, the British turning Fascist, various countries having non-historical civil wars or where aggressor nations like Germany or Japan change from their 'default' strategy. There is a large percentage of players who refuse to do anything but use the historical setting.
** The higher the difficulty level, the more players are required to restrict their research, production and unit types to the handful of specific elements of the game that make the difference in the ground combat.
*** Playing as the Soviet Union at the highest difficulty requires the player to strongly research & build basic infantry units designed to HoldTheLine and the industrial capacity to keep them all supplied until the Germans lose enough units & equipment that their attack bogs down along a Leningrad to Moscow to Stalingrad line. The Soviet Navy is completely irrelevant, and trying to build an air force will just result in them getting shot down in a few weeks and wasting the factories you used to build them. Trying to get cute by giving infantry units too much artillery, anti-tank & anti-air guns or trying to build a huge armored force will just leave you in an impossible equipment deficit once the Germans & Romanians attack, steam-roll their way through Poland and Ukraine, widening the front so much that anyone who didn't create a gigantic horde of defensive infantry units will lose.
** [[TabletopGame/Warhammer40000 Space marines]][[note]]a division consisting of marines backed by self-propelled heavy artillery and AT guns[[/note]] were so widespread and commonly used (up to the point people didn't build anything else), Paradox had to keep nerfing the related units needed to form them and ultimately, by the ''Waking the Tiger'' update, special infantry could be only fielded as a percentage of your total land forces, to keep them "special", rather than a backbone of your fighting force.
* FanNickname: Not wanting to trip the Youtube censorship bots has made it common for video creators on the platform to use a nickname for UsefulNotes/AdolfHitler. These include "Mr Schmidtler", "Gamer Germany" and "Funny Moustache Man".
* GameBreaker: Now with [[GameBreaker/HeartsOfIron their own page]].
* GoodBadBugs:
** One patch for ''Darkest Hour'' had instances where after the Soviet Union lost a war against the axis and accepting the bitter peace event, [[UsefulNotes/VladimirLenin Lenin]] would take over as Head of State of the Soviet Union, cue jokes about Zombie Lenin coming back to SetRightWhatOnceWentWrong.
*** Similarly, in ''IV'', if one sent the entire German royal family ahead to participate in the ceremony restoring the British titles, they'll still die and Von Mackensen will take power again. However, if one plays up until his death, Wilhelm III (who is dead at this point) will take over.
** A in-game overflow error in ''IV'' caused a stack of planes to go negative... leading to infinite manpower when you would try and disband the airwing.
** With the release of the “La Resistance” DLC a new achievement was added that involved Germany conquering France and Poland with 0 casualties in 1939. Players almost immediately found a glitch that allowed the control of AI nations[[note]]In version 1.9.0 it was possible to open observer mode using a loading glitch, thus allowing a player to take control of any nation and straight-up delete the nation's army and industry, as well messing with other things (changing focuses and otherwise screwing the AI). This saw the near-overnight spike of achievements as players could simply delete a AIs capability to wage war and repeat the glitch to return to their own nation[[/note]]
** A bug for ''IV'' that was patched: political focuses can be mutually exclusive, which meant that if you did one, the other was locked off (i.e., do Oppose Hitler, you lose the focuses that the fascist branch has). However, if you managed to bypass one of the two focuses, you could access both branches, which would allow you to do some very overpowered stuff[[note]]in particular, there was the aforementioned German focus tree - both political branches could be unlocked by being in a war, which would remilitarize the Rhineland, and let you bypass the focus - which made forming the European Union or Holy Roman Empire very easy, and also the Netherlands - could bypass "Curtail Colonial Autonomy" by annexing the Dutch East Indies; they could be released as a puppet again afterwards - which would allow them to both set up the Dutch East Indies for relocation after the Netherlands capitulated and do the Zurzeizee Works[[/note]].
** If you deleted all but one division, exercising it would give you tons of army XP. This was unsurprisingly patched.
** One branch of Yugoslavia's focus tree has a hidden feature - said tree breaks Yugoslavia down into the various nations that were combined into it, with the last focus allowing the player to re-annex said member states, and if their puppets had any additional cores, Yugoslavia would gain those cores as well - this would also include Bulgaria and Hungary if the player had managed to puppet them[[note]]at it's fullest extent, a player could have parts of Czechoslovakia, Romania, Greece and Italy as core territories[[/note]]. However, a bug early on gave Yugoslavia cores on any land ''occupied'' by said puppets, meaning that if one, oh say, defeated Germany and gave all of Germany to Slovenia, they'd have cores on all of Germany. This was patched, although if things go certain ways, it can still be very broken[[note]]the ability to core Bulgaria and Hungary means that the player could also core Czechoslovakia and Austria from Hungary if it reformed the Austro-Hungarian Empire, and the rest of Romania, Greece, and Albania from Bulgaria if it unified the Balkans; and of course, Yugoslavia can also gain cores on a few Italian states[[/note]].
*** A similar, but even more broken, bug involving the Imperial Federation: If one gave the states that make up the British Raj to Australia or New Zealand, the focus would core them - this might not seem broken until you realize how much manpower and factory spots are in the Raj, and that this would also give the player access to Burmese and Pakistani manpower[[note]]by default, the Raj has those lands as occupied[[/note]]. Again, unsurprisingly fixed in a patch, although similar to Yugoslavia, other cores aside from the ones the Dominions start with by default can be obtained[[note]]if New Zealand and South Africa form their formable nations, the UK cores them as well; if the player goes Monarchist or Fascist, they can have Canada core all of the United States, and lastly, a Fascist UK can form the European Union after forming the Federation[[/note]].
** Stalin's Purges in ''No Step Back'' have a few rather amusing bugs associated with them[[note]]originally, his purges were reflected with a single, 210 day focus; the new system was more akin to how it was in real life, namely, multiple waves, and you can also do single purges that target a specific general; the latter can also occur as random events[[/note]].
*** It's entirely possible for a general to accuse ''themselves'' of being disloyal. As such, you'll have three options: Believe them and purge them, not believe them and purge them for smearing their own good name, or not purge them, [[BeingGoodSucks but take a penalty for doing so]].
*** Also, one of the Soviet Union's focuses allows for Stalin to become a Field Marshal[[note]]similarly, if you do the Left Opposition, Trotsky can become a Field Marshal[[/note]]. While this focus is normally locked until you deal with Stalin's paranoia, if you somehow manage to complete it while Stalin's Paranoia is still active, it's entirely possible Stalin can purge '''himself'''[[note]]before you ask, this only removes him as a field marshal - Stalin will still lead the Union[[/note]].
*** Lastly, although extremely rare, some cases have been documented of Stalin purging generals '''''belonging to other countries'''''.
** Another bug that was discovered after the release of ''No Step Back'': the continuous focus Naval Production would grant players a 20% boost to dockyard output. However, it's been discovered that if you constantly start and restart the focus, it will stack, which means you can reach a production bonus in the ''hundreds'' without any tech bonuses - not only does this make it practical for Germany and France to catch up to the larger navies with just screen ships, but it also makes achievements such as My Ships don't Lie[[note]]which requires the production of multiple capital ships[[/note]] and Vive la Jeune Ecole[[note]]producing over 150 destroyers as France[[/note]] laughably easy.
** One achievement for Battle for the Bosphorous ("One Nation Under Ataturk") normally would only work after you had removed the negative state modifiers...but on the patch that was released with the DLC, it was discovered that if you loaded a game as Turkey without the DLC activated, you'd get the achievement the second you started the game. This was patched, although those that earned the achievement still got to keep it.
** When Germany capitulates France while France is part of another faction, isn't the faction leader, and the faction leader hasn't capitulated, Germany can establish Vichy France[[note]]if this happens with a Monarchist Germany, they can establish Bourbon France instead[[/note]] - however, if France is able to retake Paris, Vichy France will get an event where they get to allow themselves to be annexed by France[[note]]provided they were formed, obviously[[/note]], likely to account for cases where the Allies are able to land on Europe before Vichy France is dragged in[[note]]in the current game, one of Vichy France's focuses will generate tension, thus allowing the Allies to justify on them and get them involved, giving Free France a chance at retaking the Vichy held lands, as doing so would drag Vichy France into the war; however, if the Allies are able to retake Paris before that point, then Vichy France would not join the Axis[[/note]]. However, the game doesn't check if the France in possession of Paris is independent, meaning that if the player either puppets Free France and ensures they have Paris in their control, or establishes a collaboration government, then their French puppet will automatically annex Vichy France, giving the player control over all of Vichy France for free - in particular, it's much more practical for Germany to gain access to the French Navy this way than through Case Anton. And this isn't limited to Germany either - any country can do this if Vichy France was formed.
*** A variation of this bug from the early days of the game: If you played as Italy and did the focus "Demand Baleric Islands", doing so would have Nationalist Spain either agree to part with the islands or refuse. If you got the islands and then released Republican Spain as a puppet, however, doing so would cause the event that fires whenever two countries of the same ideology are at a civil war to fire off, which would cause Republican Spain to annex Nationalist Spain!
* JustHereForGodzilla: [=HOI4=]'s extremely active and highly popular modding community has resulted in many players getting [=HOI4=] just for the mods, often completely ignoring the base game.
* MemeticBadass:
** The minor Asian country of Bhutan in [=HOI4=] has the fascist country name of ''Thunder Dragon Empire''. The over-the-top nature of the name led to many memeing the country as though it was a superpower.
** Luxembourg, the weakest country in [=HOI4=] at game start, has attracted many players looking for a challenge. There are many [[SelfImposedChallenge world conquest]] runs as Luxembourg out there on the internet, which has resulted in Luxembourg being memed as an extremely dangerous country in the playerbase.
* MemeticLoser:
** Italy is mocked as one by the fanbase, due to the sheer incompetence of its AI. It is especially apparent in ''IV'', where it does worse than it did in the real-World War 2, getting quickly ejected from North Africa, failing even worse at invading Greece, and almost inevitably failing to stop the British & US from naval invading its homeland. Italy is so bad that should anyone intervene in Ethiopia on the Ethiopian side, Italians might end up being bogged down in that war for years or even lose. Italy wound up being the last of the 7 starting majors to get a reworked focus tree, receiving theirs in ''By Blood Alone'', after the Soviet Union got one in ''No Step Back''. This has slowly started to change over the years with Italy now being treated as something of a {{Woobie}} for being sidelined by Paradox for years.
** The Democratic alternate history paths for most countries are often maligned for being boring and underpowered. They’re often oriented towards being more defensive, which can remove a lot of chances for the actual meat of the game- the warfare- to play out.
* MemeticMutation:
** ''Tannu What?" [[note]]Tannu Tuva is a small socialist nation sandwiched between Mongolia and the USSR. The nation is so small and obscure that when the Soviet Union completes the focus, a global event fires saying that the small country was annexed and the only answer of the countries is Tannu [[FlatWhat what?]][[/note]]
** What if X won World War 1?[[note]]The original user of this meme is the large mod ''VideoGame/KaiserreichLegacyOfTheWeltkrieg'' with the subtitle [[Main/AlternateHistory "What if Germany won World War 1"]]. The popularity of ''Kaiserreich'' led to many derived mods (most of which never got past the conceptual stage) and thus derived memes, such as "What if Belgium won World War 1?", "What if Russia won World War 1?", and things like "What if nobody won World War 1?" (which eventually got its own mod called ''VideoGame/RedFlood'') or "What if ISIS won World War 1?". The mod ''VideoGame/FuhrerreichLegacyOfTheGreatWar'' is also a case of "What if the Allies won World War 1?", in a sense parodying the meme.[[/note]]
** ''El Generico'' is the name used to refer to a [[https://i.imgur.com/3EFoPqX.png specific generic portrait]] used for Latin American heads of state that didn't have portraits, the problem is that most of Latin American nations didn't have any portraits and for some reason, despite having multiple generic portraits in the files, the game would ALWAYS choose ''El Generico'', having the hilarious consequence of him leading multiple countries at the same times and when the country's ideology changed he would just change his suit or add a small hammer-and-sickle pin on the suit.
** ''High Hopes: Liberia DLC'', a joke regarding Paradox policy of making completely ahistorical and unbalanced focus trees for minor countries, especially if they didn't even take part in any [=WW2=] military engagements. With the backdraft created by Mexico's focus tree announcement, the meme returned with double the force, despite it being originally created as a reaction toward the lack of balance in the (real) ''Death or Dishonor'' DLC released in 2017.
** ''Komet Sighted'', doubles as a MythologyGag due to almost every Paradox game including "comet sighted"
** The "[[https://www.youtube.com/watch?v=44RoK_4qAcQ Battle of Wuhan]]" track from ''[=HoI4=]'' OST has been used as meme fodder due to the UsefulNotes/CoronavirusDisease2019Pandemic which originated in Wuhan.
** The abundance of AlternateHistory-themed mod in general, and the fact many of them were dark settings (notably, ''VideoGame/RedFlood'' and ''VideoGame/TheNewOrderLastDaysofEurope'') resulted in an in-joke about the modding scene being a contest to create the most [[CrapsackWorld "cursed timeline"]].
** A very popular way to "play" ''IV'' is for players to recreate all sorts of scenarios with mods, be it real or fictional with every faction played by the AI, before sitting back and watching the time-lapse to see which faction eventually is the winner. Jokes regarding DarkhorseVictory ran rampant with the results.
** Italy will never get a new focus tree[[note]]Despite various changes in the game since release and new focus trees for various countries along with reworks of existing ones, Italy is still stuck in its original, release-state tree. This even including the changes made with Spanish Civil War, and all the trees being adjusted... except for Italian one.[[/note]]. Likely on it's way to DiscreditedMeme after the announcement of ''By Blood Alone'', which featured a new focus tree for Italy.
** It's a running joke in the community that no one actually understands the naval system in ''IV''.
* {{Narm}}: The Allied Speeches Pack became a butt of jokes immediately after announcement, partly because it charges money for a bunch of public domain speeches that people can find for free and add to the game via mods, and partly because the "Allied" word in the title only draws attention to the fact that an "Axis Speeches Pack" would never be a thing, for [[MasterRace obvious]] [[GuiltFreeExterminationWar reasons]].
* TheScrappy:
** In ''IV'', Central and South American nations are generally mocked by the player base for a multitude of reasons:
*** No nation south of Mexico has a unique focus tree leading to very little action in the entire region.
*** They typically have very little impact on gameplay but major impact on performance as the AI will favour doing nothing but spamming units the entire time but never declaring war. El Salvador is a meme in the community for sitting on it's two tiny provinces and doing nothing but creating dozens of units.
*** The terrain in the regions is primarily jungles, swamps and mountains as well as impassable regions making logistics nigh impossible, made even worse by the new logistic systems added into the game.
*** Due to the Monroe doctrine by the US if any non American nation decides to invade the hemisphere America will instantly intervene.
** In online multiplayer games anyone who picks France and then rejects the Rhineland remilitarization will get kicked & banned because it completely ruins the game, wasting the time of everyone who was playing in it.
* ScrappyMechanic:
** Except for ''I''[[note]]Only new models of tanks, planes and ships have the familiar upgrade system that more or less builds the whole thing anew at half the price, while everything else just receiving stat bonuses directly after research is done[[/note]] and ''Darkest Hour'' [[note]]Where you have to specifically order each unit separately to do so[[/note]], no other game in the series offers to directly upgrade your units to top of the line gear - you always do it step-by-step. This is particularly annoying in ''III'', where you've got dozens upon dozens of technologies and thus statistics that each has to be upgraded separately[[note]]For example, your infantry isn't just upgrading in general, it is keeping separate track of what tier are defensive weapons, service rifles, support gear or doctrines and how close to next tier the upgrades are, with bonus to upgrade speed for each of those also taken separately[[/note]] and ''always'' only one step forward. Having high technology, but the fielded army being obsolete? Tough luck, you going to spend ''years'' re-equipping those, of course assuming you've got the industrial capacity to afford that. In fact, in ''III'', unlocking too many one-tier technologies can bog down your entire industry, since you have your entire army applying new gizmos to it, ramping up the costs of upgrades per unit and thus meaning you can't afford the general upgrades, turning the whole thing into a logistical nightmare. And units only upgrade when out of combat, so good luck with that past the 1940 mark. ''IV'' significantly retooled the whole system, since better gear to your units has to be produced first, but it is issued only when out of combat.
** In ''II'' and thus ''Darkest Hour'', light tanks automatically upgrade to medium ones. Unless you explicitly flag the unit to be exempt from upgrades, it will start gearing toward the lowest tier of medium tanks, which is rarely desirable. Not to mention building medium tanks directly is much cheaper and faster.
** Naval invasions are a pain in the ass to do in ''IV'', and are poorly explained by the game as it requires naval supremacy over the location the invasion will take place and there are some harsh restrictions on how many units you can use in the early game (which some nations requiring an easily missed technology to do it). It doesn't help that the AI is abysmal at doing them. Even if the German lead Axis smash the Soviets and control Europe, the AI is often completely incapable of winning naval supremacy over the home waters around England, resulting in a stalemate until the US enters the war at which point the US & UK can win supremacy only to throw away divisions in poorly designed naval assaults often with as little as one unit. Invasions of the USA by Japan or vice versa will also leave the player waiting years unless they do it themselves.
** The UI element for creating air forces is dreadful in ''IV''. Absent even a basic ability to filter the list by plane type and tier, it just lists every single individual model of aircraft in a long list which is in a very small window. In any prolonged war, you will capture dozens of different types of planes and will get thoroughly sick of scrolling through the list to find exactly which one you want. Additionally, the way air reinforcements work is that any variant or new model will automatically replace any existing deployment. This doesn't help the clutter of the UI because your list will always keep filling up with the worst models you have made as they get replaced by the new one. Paradox eventually added the ability to trash vehicles, behind a DLC paywall of course.
** The spy/espionage mechanic in ''IV'' is generally regarded as underwhelming, if not outright useless, with the only practical operations being setting up collaborationist governments or having spies suppress resistance in occupied territory. All of the other covert operations have such negligible effects they're not even worth bothering conducting. The huge industrial and time investments required also mean only major powers will be able to set up an intelligence agency and even then, you'll be lucky if you even get one collaborationist government ready before the war kicks off.
** At the peace treaty with happens to end a war, the number of casualties is one of the biggest contributors to the war score, the point system which determines how the defeated lands are settled. This can be very frustrating for a player that effectively done most of the work conquering the most lands with minimal casualties...only to lose most of them to another party that kept throwing their armies into a meat grinder stalemate and racking up casualties. [[SarcasmMode Yeah, because that is totally how you measure the performance of a winning faction]]. Not to mention, if said party is your next target, this means you have to ''conquer the same lands again''.
** In ''IV'', if you want to release a nation or form a Collaboration Government, you have to release all states they own...even if one of the states they own is a core of yours. Wanna release France as a puppet after forming the Holy Roman Empire so you can steal their manpower? Say goodbye to Savoy and Alsace-Lorraine. An especially annoying version of this is if the country you're trying to release ''gains'' a core on a state - if Poland annexes Germany and then gets enough compliance to form a collaboration government, if Germany did Danzig or War, Poland will lose Danzig in the process.
** The random purges in ''No Step Back'' would be fine if it wasn't for a combination of the fact that a), the only way a general or admiral can avoid being purged is if they have Stalinist Loyalties (which can be annoying if you're going for a civil war to overthrow Stalin, as generals with said loyalties will side with Stalin when the war breaks out), and b), Stalin can even target generals who, historically, he did not purge (i.e., Georgy Zhukov, Konstantin Rokossovsky, Aleksandr Vasilevsky), even if you're playing the historical route. There's also the fact that it's entirely possible for the player to have the bad luck of having Stalin ''purge their entire roster of generals'', meaning that you have to waste command power to generate new ones - which wouldn't be so bad if it wasn't for the fact that the high command now requires command power in addition to political power. For that matter, if you go for the Right Opposition, you had better hope that he doesn't randomly purge Alexei Rykov or Nikolai Bukharin, because if he does, then a good chunk of that path is locked out[[note]]the Left Opposition can send it's leaders and advisors into exile, thus allowing them to avoid being purged[[/note]].
** The Stalin Paranoia mechanic being introduced really bought to a head complaints & arguments in the fanbase about Paradox stuffing the game full of what the community call "mini-games" where you have to manage esoteric country specific mechanics that do away with the regular way of managing your country. These include certain civil wars having you build support per province, border conflicts, the US congressional politics mechanic that no-one else in the game uses, Turkish, Dutch & Greek investment decisions, the Chinese warlords and the Bulgaria focus tree.
** The additional guarantees that Paradox added to the game make early wars as smaller non-democratic powers much harder to do, as you bring down the full weight of factions on you rather than a limit war between two nations.
* SelfImposedChallenge: There are plenty of nations that are much weaker than the major powers the player can play as and try to beat the historical odds.
* StockParodyJokes: ArgentinaIsNaziland-themed jokes abound, thanks to the "Señor Hilter" events chain (Hitler in a PaperThinDisguise as a fascist leader in Argentina after a Nazi defeat in a German civil war).
* SurprisinglyImprovedSequel: The first game was a very basic reskin of ''VideoGame/EuropaUniversalis'' and was pretty meh, along with similar critical reception, and was quickly discontinued from support. It wasn't until ''II'' that the series really found its niche and all the mechanics were polished, providing important details and room for any meaningful modding. Effect? An entire bunch of mods, with ''Darkest Hour'' being eventually released as its own game and loyal playerbase to justify the rest of the series.
* SuspiciouslySimilarSong: The Allies' themes in ''[[https://www.youtube.com/watch?v=tPUpRBmcuOo&index=5&list=PLB55FF169BD130E9E III]]'' and ''[[https://www.youtube.com/watch?v=7ITkwsycObs#t=01m03s IV]]'' are rather similar to the main [[https://www.youtube.com/watch?v=7uTAIpU0sa0b theme]] of ''Series/BandOfBrothers''.
* TierInducedScrappy: Ever since army doctrines were introduced in ''II'', Grand Battle Plan is consistently overshadowed by better picks, is clearly weaker than alternatives, requires some specific gimmick to shine or any combination of the three. In ''II'' and ''Darkest Hour'' it is particularly awful due to the way how research works in those. Since research is done by tech teams and they come with pre-definied specialisations, chances are if your country has a team geared for researching Grand Battle Plan doctrine, it won't have alternative doctrinal team. And researching lackluster doctrine is still better than trying to catch-up in different field without a specialist.
* TheyChangedItNowItSucks: Numerous elements of gameplay were completely retooled with 4th game, with really mixed reception, to say at least:
** Garrison and militia battalions were completely removed from the game, forcing players to design their own rear guards from costly infantry or unsuitable cavalry. While it's not problematic by itself, it can quickly get simply ''annoying'' to manage - especially if it might end up costing precious army experience to even design such units in the first place. Garrisons were put back into the game for ''La Resistance'', while Militia units can be vaguely designed by setting up Infantry units that have no support companies.
** As of the 1.5.3 patch, Artillery regiments have been repeatably nerfed, so much so that the original strategy of using 14INF:4ART or 7INF:2ART[[note]] 14 infantry and 4 artillery or 7 Infantry and 2 artillery respectively in as a division template [[/note]] is no longer a viable strategy [[ObviousRulePatch in an attempt to make players experiment with other designs]] and micro-manage their troops on the front line. But since it's still ''the'' best set up for infantry divisions, all it achieved was a half-hearted nerf amid a massive outrage. On higher difficulties, the nerf does bite though, as attempting to make such big artillery-heavy divisions will often cause massive supply problems down the line.
* UnexpectedCharacter:
** While it's hard to call any country ''existing'' unexpected, few if any people would have expected Mexico to get a focus tree in a naval focused DLC, or under any circumstances get one before Belgium, Spain, or Scandinavia, but in large part due to bordering the USA, which was part of the main focus, Mexico also got a focus tree in ''Man the Guns''.
** Repeated in the ''La Resistance'' DLC, with both Portugal and the Spanish receiving reworks, when it was expected that the Soviets would get a much-needed buff[=/=]rework[[note]]To put this in perspective, the Soviet Union has not had their focus tree reworked since the release of IV (until ''No Step Back'', the ''seventh'' major DLC), meaning the Dutch, Spanish, Manchu, Mexican and Portuguese have received more attention[[/note]]. Portugal is an especially weird choice, as it stayed intentionally neutral throughout most of the war and unlike Mexico, doesn't even offer any sort of counter-balance mechanically.
** Repeated again in the ''Battle for the Bosporus'' DLC, which adds content for Turkey, Greece, and Bulgaria (respectively a neutral country, a minor Allies member, and a minor Axis member).
** While the Soviet Union and Poland were expected to get reworks in ''No Step Back'', the Baltic states (which largely did little aside from being annexed by the USSR) getting focus trees as part of said DLC was not, given that many expected Finland to receive a focus tree instead.
** ''By Blood Alone'' continued this trend - while Italy's rework was guaranteed, and Ethiopia had been predicted by some, the third nation in the pack was ''Switzerland'', which is famous for it's policy of absolute neutrality - many fans expected Austria or Albania to round out this trio, given that their role in the game on historical is not that different from Czechoslovakia, which did get a focus tree.
** Not only can [[https://en.wikipedia.org/wiki/Wojtek_(bear) Wojtek the Bear]][[note]]a Syrian brown bear who was adopted in 1942 by Polish soldiers while they were stationed in Iran, and was officially enlisted as a soldier in an artillery supply company. He notably took part in the Battle of Monte Cassino[[/note]] be promoted as a commander for Poland, but the ''No Step Back'' DLC adds him as ''one of the claimants for the throne of Poland''!
* TrollingCreator: A specific set of circumstances (some player influenced, some random) allow Victoria Louise to be crowned as Kaiserin of a restored UsefulNotes/ImperialGermany (and possibly the UsefulNotes/HolyRomanEmpire). Her regal title? Victoria III. The Paradox fanbase always hoped that the next game announced would be a sequel to ''[[VideoGame/VictoriaAnEmpireUnderTheSun Victoria II]], which happened in 2021.''.

** Italy will never get a new focus tree[[note]]Despite various changes in the game since release and new focus trees for various countries along with reworks of existing ones, Italy is still stuck in its original, release-state tree. This even including the changes made with Spanish Civil War, and all the trees being adjusted... except fot Italian one.[[/note]].

* TheScrappy: In ''IV'', Central and South American nations are generally mocked by the player base for a multitude of reasons:
** No nation south of Mexico has a unique focus tree leading to very little action in the entire region.
** They typically have very little impact on gameplay but major impact on performance as the AI will favour doing nothing but spamming units the entire time but never declaring war. El Salvador is a meme in the community for sitting on it's two tiny provinces and doing nothing but creating dozens of units.
** The terrain in the regions is primarily jungles, swamps and mountains as well as impassable regions making logistics nigh impossible, made even worse by the new logistic systems added into the game.
** Due to the Monroe doctrine by the US if any non American nation decides to invade the hemisphere America will instantly intervene.

** In ''IV'', if you want to release a nation, you have to release all states they own...even if one of the states they own is a core of yours. Wanna release France as a puppet after forming the Holy Roman Empire so you can steal their manpower? Say goodbye to Savoy and Alsace-Lorraine.

** One branch of Yugoslavia's focus tree has a hidden feature - said tree breaks Yugoslavia down into the various nations that were combined into it, with the last focus allowing the player to re-annex said member states, and if their puppets had any additional cores, Yugoslavia would gain those cores as well - this would also include Bulgaria and Hungary if the player had managed to puppet them[[note]] at it's fullest extent, a player could have parts of Czechoslovakia, Romania, Greece and Italy as core territories[[/note]]. However, a bug early on gave Yugoslavia cores on any land ''occupied'' by said puppets, meaning that if one, oh say, defeated Germany and gave all of Germany to Slovenia, they'd have cores on all of Germany. This was patched, although if things go certain ways, it can still be very broken[[note]]the ability to core Bulgaria and Hungary means that the player could also core Czechoslovakia and Austria from Hungary if it reformed the Austro-Hungarian Empire, and the rest of Romania, Greece, and Albania from Bulgaria if it unified the Balkans[[/note]].

** When Germany capitulates France while France is part of another faction, isn't the faction leader, and the faction leader hasn't capitulated, Germany can establish Vichy France[[note]]if this happens with a Monarchist Germany, they can establish Bourbon France instead[[/note]] - however, if France is able to retake Paris, Vichy France will get an event where they get to allow themselves to be annexed by France[[note]]provided they were formed, obviously[[/note]], likely to account for cases where the Allies are able to land on Europe before Vichy France is dragged in[[note]]in the current game, one of Vichy France's focuses will generate tension, thus allowing the Allies to justify on them and get them involved, giving Free France a chance at retaking the Vichy held lands[[/note]]. However, the game doesn't check if the France in possession of Paris is independent, meaning that if the player either puppets Free France and ensures they have Paris in their control, or establishes a collaboration government, then their French puppet will automatically annex Vichy France, giving the player control over all of Vichy France for free - in particular, it's much more practical for Germany to gain access to the French Navy this way than through Case Anton.

** Italy is mocked as one by the fanbase, due to the sheer incompetence of its AI. It is especially apparent in ''IV'', where it does worse than it did in the real-World War 2, getting quickly ejected from North Africa, failing even worse at invading Greece, and almost inevitably failing to stop the British & US from naval invading its homeland. Italy is so bad that should anyone intervene in Ethiopia on the Ethiopian side, Italians might end up being bogged down in that war for years or even lose. With the release of ''No Step Back'' DLC, Italy is also the only remaining major to not have a focus-tree revamp. This has slowly started to change over the years with Italy now being treated as something of a {{Woobie}} for being sidelined by Paradox for years.

** When Germany capitulates France while France is part of another faction, isn't the faction leader, and the faction leader hasn't capitulated, Germany can establish Vichy France - however, if France is able to retake Paris, Vichy France will get an event where they get to allow themselves to be annexed by France[[note]]provided they were formed, obviously[[/note]]. However, the game doesn't check if the France in possession of Paris is independent, meaning that if the player either puppets Free France and ensures they have Paris in their control, or establishes a collaboration government, then their French puppet will automatically annex Vichy France, giving the player control over all of Vichy France for free - in particular, it's much more practical for Germany to gain access to the French Navy this way than through Case Anton.

* FanNickname: Not wanting to trip the Youtube censorship bots has made it common for video creators on the platform to use a nickname for UsefulNotes/AdolfHitler. These include "Mr Schmidtler" and "Funny Moustache Man".

* CriticalResearchFailure:
** A generic Pol Pot leads Cambodia if it's communist. He was 11 in 1936, and his in-game sub-ideology is "Anarcho-Communism"
** Similarly, Fidel Castro is a minister for Cuba. He was 10 in 1936.
** [[UsefulNotes/JuanDomingoPeron Juan Perón]] is a Minister labeled "Communist Revolutionary". Peronism is a difficult ideology to pinpoint it's location in the ideological scale, but as Perón himself famously said: "What has Cámpora done to me? he has filled my government with leftists and whores".
** Enver Hoxha, a strict anti-revisionist Marxist, who famously denounced Maoism, is a weird case. While he appears as the Communist Albanian leader, on the Minister tab he is labeled a "Democratic Reformer", so if Enver Hoxha as a minister was on Enver Hoxha's communist rule, [[MindScrew he would reduce his own popularity]].
** Getúlio Vargas, is portrayed as Non-Aligned on the start. While this might be true in the start diplomatically, he ruled his dictatorship like a very much like a fascist, but went on to officially join the Allies[[note]]this was likely done because of the fact that, if world tension gets high enough, Venezuela, Peru, El Salvador, and the Dominican Republic - all Fascist - can join the Axis, meaning Brazil would likely follow suit; Vargas can become the leader of Fascist Brazil...if Portugal moves to restore the monarchy[[/note]].

* TierInducedScrappy: Ever since army doctrines were introduced in ''II'', Grand Battle Plan is consistently overshadowed by better picks, is clearly weaker than alternatives, requires some specific gimmick to shine or any combination of the three. In ''II'' and ''Darkest Hour'' it is particularly awful due to the way how research works in those. Since research is done by tech teams and their come with pre-definied specialisations, chances are if your country has a team geared for researching Grand Battle Plan doctrine, it won't have alternative team. And researching lackluster doctrine is still better than trying to catch-up in different field without a specialist.

** While it's hard to call any country ''existing'' unexpected, few if any people would have expected Mexico to get a focus tree in a naval focused DLC, or to under any circumstances get one before Belgium, Spain, or Scandinavia, but in large part due to bordering the USA, which was part of the main focus, Mexico also got a focus tree in ''Man the Guns''.

** They typically have very little impact on gameplay but major impact on performance as the AI will favor doing nothing but spamming units the entire time but never declaring war. El Salvador is a meme in the community for sitting on it's two tiny provinces and doing nothing but creating dozens of units.
** The terrain in the regions is primarily jungles and swamps with several impassable regions making logistics nigh impossible.

** Italy will never get a new focus tree.

** Italy is mocked as one by the fanbase, due to the sheer incompetence of its AI. It is especially apparent in ''IV'', where it does worse than it did in the real-World War 2, getting quickly ejected from North Africa, failing even worse at invading Greece, and almost inevitably failing to stop the British & US from naval invading its homeland. Italy is so bad that should anyone intervene in Ethiopia on the Ethiopian side, Italians might end up being bogged down in that war for years or even lose. With the release of ''No Step Back'' DLC, Italy is also the only remaining major to not have a focus-tree revamp.

** The Stalin Paranoia mechanic being introduced really bought to a head complaints & arguments in the fanbase about Paradox stuffing the game full of what the community call "mini-games" where you have to manage esoteric country specific mechanics that do away with the regular way of managing your country. These include certain civil wars having you build support per province, border conflicts, the US parliament mechanic that no-one else in the game uses, Turkish, Dutch & Greek investment decisions, the Chinese warlords and the Bulgaria focus tree.