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Thursday, July 11, 2024

How to build most overpowered custom nations in Europa Universalis IV 1.37

Custom nations have been in the game since El Dorado DLC. When setting up a custom nation, everything costs points, and there are some targets like 200 for a "normal" start, 400 for "easy", and 800 "very easy".

This was always very poorly balanced, and initially custom nations bonuses were weak. But EU4 went through a lot of power creep, and some of the recent custom nations bonuses are really overpowered.

To make OP custom nation, the best way is to make geographically smallest country that's viable, and put all the point in ideas. Viable might mean a single province on most of the map, but for some particularly hostile areas, you might want to make it a bit bigger.

You don't really get 200 points. There's no reason not to take always duchy rank (-10 cost), 0/0/0 age 0 heir (-24 points, will get disinherited immediately), and 0/0/0 consort with irrelevant negative trait like Loose Lips (only -4 points, but might as well take it). You should also take bad trait for your ruler that doesn't matter like Loose Lips (-20% foreign spy detection) or Malevolent (+5% Liberty desire in subjects), but that only gives you -2 points. So your starting budget is 240.

Unfortunately we can't just take 240 points worth of ideas from the menu. There are 10 bonus slots, but slot costs is multiplied by 2.0, 2.0 (two traditions), 2.0, 1.8, 1.6, 1.4, 1.2, 1.0, 1.0 (7 ideas), and 1.0 (ambition). So if we spread idea points evenly, average cost is 1.5x, so we have 16 points to spend per slot to fit our 240 point budget (a bit less as you need at least some land). If you frontload cheap ideas, and end with expensive ideas, you can get a bit better value, but it will obviously make your early game harder.

There's also huge penalty for taking too many levels from the same category. Try to avoid it. Sometimes getting extra levels of ideas makes total cost cheaper! The most broken ideas are in admin or diplo category, so it might be challenging.

You can also increase your budget by taking a negative idea for negative cost:

  • Can NOT declare war for -100
  • Can NOT build buildings for -40
  • Can NOT send merchants for -40
  • Can NOT build over force limit for -25
  • Can NOT establish colonies for -10
  • Can NOT send missionaries for -10

You should always stick these in your 2.0x slot. The alternative of sticking them in your ambition and never taking 3 full idea groups is honestly not worth it. Of these, the only one I'd really consider is the force limit ban. Colonies/missionaries are not worth many points, and the rest are too harmful to you. Sticking a ban on building over force limit as your first tradition gives you 50 more points, and it won't even apply very early game when you're most likely to do this.

Custom nations can form other nations. This is the only way to get new mission trees, some with a lot of overpowered bonuses as mission rewards. But even if you form a new nation, you can't change ideas you originally selected.

Anyway, let's get to the completely broken ideas.

Overpowered Economic Ideas

For 60 points you get flat +2 goods produced. That's equivalent to 10 dev per province, including gold mines. None of the other economic modifier are even in the same ballpark. If your average province is 3/3/3, it will get +333% production income, +333% trade value (it goes into trade node, so you still need to capture it), I have no idea what they've been thinking. For comparison with some pre power creep modifiers, 18 points gets you 20% production efficiency, and 30 points gets you 20% trade efficiency. If you don't have points budget for it, you can get +0.5, +1, or +1.5 for proportionally less points.

Overpowered Military Ideas

Military bonuses are mostly either crap or really overcosted. The game wants you to pay 18 points for crap like -20% recruitment speed. Or for something more ridiculous, +2 leader fire or shock costs ridiculous 140 points, not even remotely worth the cost.

There are just two military ideas worth looking into. The less broken one is Triple manpower increase in religious wars for 50 points, which is basically triple manpower always, as you can always find some infidel OPM to "fight".

The second one that's even better are +1 Infantry Fire and +1 Infantry Shock for 25 points each. These are completely unrelated to unit pip stuff. It's just ridiculous early game. Normally fire and shock of military units depends on tech, and at tech 3, infantry has total of 0.85. If you got both bonuses in your traditions, your infantry will be doing 2.85x damage instead, or +225% more damage. It just melts enemies.

This is somewhat balanced by two things. As game progresses, base shock and fire values for all units increase, so by the end of tech tree, infantry has 5.25 total, or 7.25 with both bonuses, which is respectable but less ground breaking +38% increase. A much bigger factor is that your army composition changes from all infantry to half infantry half artillery, and artillery doesn't get any bonus. By end of the game backrow artillery deals a bit less damage than front row infantry (fire + shock is 8.95, but only half of that counts for backrow units; disregarding pip differences), so this bonus is worth about +20% more damage by 1821. Not game-chaging by then, but still respectable.

Due to the way combat math works with fire and shock phases switching back and forth every five days, both bonuses are almost equivalent, except fire phase happens first, so Infantry Fire +1 is a bit superior to Infantry Shock +1. This is disregarding pip distribution and such, but they don't really change much. Obviously if you use this build, delete all your cavalry.

The obvious question is about doing it for cavalry and artillery. It's mostly just worse, but worse version of ridiculously overpowered is still pretty good.

It's a flat bonus per unit, so for cavalry you'd get same extra damage for 2.5x as much unit upkeep. This only makes sense if you build all cavalry armies (and eventually cavalry + artillery armies). If you mix cavalry with infantry you're watering down your bonuses even more. And penalties for too much cavalry are so high, that there's no way taking cavalry fire and shock without 100%+ cavalry to infantry ratio is a good idea. Base is 50% and you can take cavalry to infantry ratio bonuses in custom ideas (+60% for 18 points), and you and get some from religion (+25% pure Tengri, +10% Sunni) and various government reforms like Steppe Horde. It's mostly a weaker version of infantry bonuses, but it's still strong, going from +200% at tech 3 to +33% at 1821 all-cavalry army, or +19% for 1821 cavalry/artillery army.

Artillery bonuses are noticeably worse. Because artillery is normally in the backrow, you'll only be getting half the bonus, so it gets +0% for early game armies, by midgame if you switch to half inf/half art armies at tech 16 it peaks at +28% (infantry bonus would be +56% at this point), and only +10% by 1821.

There's one exception to this. If you build your armies with just artillery, with no infantry, and no cavalry, the bonus will be +190% damage at tech 7, gradually falling to +22% in 1821. But your artillery will also take double damage. It's a bit of a meme build, but these ideas make it sort of viable.

And yes, for both cavalry and artillery, +1 fire and +1 shock are pretty much the same thing.

Overpowered Province Warscore Cost

Province Warscore Cost is a modifier that's fairly mid when you have a bit of it, but stupidly overpowered when you stack it near -90% cap. It turns out custom nations let you do this stacking really easily. 25 points will get you -25% province warscore cost, 18 points will get you -25% province warscore cost against other religions, and then you can take Diplomatic (very decent idea group) for -20% more, having -50% discount in 1444, and -70% discount as early as 1460s. At this point you really want to keep stacking it, and Age of Reformation gives you −25% more against other religion, already taking you over the cap. Other good sources are Malta monuments that go to -15%, and Mecca monuments that go to -10% but only for Muslims. You could also get −10% for military hegemony.

AIs will be giving you land practically for free, but you still need to get your AE and OE management game. This build relies on your religion being different, so picking Catholic or Sunni is notable counter-production. There's no real reason to pick Sunni anyway, Shia and Ibadi are mechanically almost identical to Sunni, and picking either gets you access to Mecca monument, so it's a great build.

Switching from Catholic to another Christian religion is more costly, as Catholic is by far the strongest Christian denomination since Emperor DLC (usually whoever got the most recent DLC is the strongest). Christian Europe is also a relatively poor way for going ham on province warscore cost, as you'd be facing coalition of the whole continent in no time. But even with these issues, it's still not a bad build. You'll be getting up to -90% against other religions (Council of Trent provides the last −10%, if they vote right) and -45% against other Catholics (-25% custom ideas, -20% from diplomatic ideas).

Overpowered Monarch Point Savings

All Power Cost. You can get literally -10% all power costs for 60 points. By midgame you'll be making about 13 points per month of each kind (3 base, 1 power projection, 5 advisor, and thanks to disinheritance and abdication monarchs average 11-12 points so that's about 4 of each type), so that's about 45 monarch points saved every year.

Administrative Efficiency. 10% costs 60 points. It's best if you stack it, unfortunately you'll need to wait for Age of Absolutism to start really stacking it. Until then you can get 5% more from Alhambra monument, and some more from mission trees.

Administrative Honorable Mentions

-20% coring cost reduction for 30 points. This would have been a top tier idea, but power creep went so far it's merely an honorable mention now. CCR is obviously good, and it's even better if you stack it, so take administrative ideas for −25%, and then you can squeeze the last percentages from your religions (Hindu can get the most -10% for Shiva plus another -10% for Kashi Vishwanath Temple monument) and mission rewards.

+1 colonist for 30 points. The first colonist is far more valuable than additional colonists, and you can get one for really cheap. This used to be somewhat limited, as you had to wait for maps, but nowadays if you have a colonist, you can get free explorer from your estates and do exploring, so that problem is completely gone. It depends on your location, but you can get far ahead on colonization if you put this in your traditions. On the other hand starting too early you might struggle with colonial range.

+20% goods produced for 30 points. This is decent economic modifier, and it becomes a lot more valuable once you get manufactories going everywhere. It's nowhere near as good as flat goods produced - if average province is 3/3/3 (0.6 goods produced), +20% bonus gives you +0.12 early game, and +0.32 after manufactories, while flat +1 for the same price gives you +1. You can stack percentile bonus and also flat bonus, and you'll run out of things to spend money on halfway through the game.

-20% minimum autonomy in territories for 18 points. This also applies to trade companies, but you can stack it with -20% from economic hegemon, -10% from expansion ideas, typically -10% from government reforms, for trade company autonomy cap of just 30%, or 7x the manpower and tax you'd be getting normally. You could get it even lower with Hindu or Confucian monuments.

+40% Governing capacity modifier for 30 points. You can normally keep up with governing capacity with technologies, estates, and buildings even when expanding rapidly, but bonus you can get here is surprisingly large. The most any normal nation gets is +15%, and even that is rare.

Diplomatic Honorable Mentions

-20% Aggressive expansion impact for 30 points. Not quite as good as −25% that Ryukyu gets in base game. This modifier is best when you stack it, so definitely take Espionage ideas for -20%. It's mediocre normally, but it's really useful for this build. Age of Discovery has ability for -10%. Maxed out prestige is another -10%. The Grand Palace of Bangkok monument is -10%. Many religions can top it off. Orthodox can get -10% from icon, Muslims can get -10% from Hanbali scholar, Hindu can ge -5% from Shiva deity and -10% more from Kashi Vishwanath Temple monument. Catholics can get -10% from a bull, and -20% from curia control, but you can't count on consistently having either.

-20% diplomatic annexation cost for 30 points. This is best if you stack it. You'll need to take Influence ideas for −25%. Estate privilege Nobility Integration Policy gives you -5%. Influence-Administrative policy gives another -15%, and you're probably taking Administrative anyway, so that's already -65%. Pushing it further is harder. Influence-Quality policy is extra -10% but Quality is a weak idea group you probably wouldn't want normally. Curia controller is −10%, but that's not reliable. Parliament can have an issue for -15% if you have two or more annexable subjects. Quite a few countries have a discount as mission reward, so if you want to form some nations on the way, that's your best way to reach the -90% cap.

+30 Vassalization Acceptance for 5 points. This is equivalent to 10 whole diplomatic reputation, for this one interaction. This is way better if you stack it, so you should definitely take Espionage for +15 more bonus. You'll probably want Influence for 2 diplomatic reputation (+6 more bonus) and cheaper annexation cost, the game has a lot of other diplomatic reputation bonuses to pick up. Going all into vassalization game leads to a very different gameplay than normal. If you want to try this in Europe, you should consider destroying HRE and getting the pieces as vassals. The main limitation of this is diplomatic relations limit, there's some DLC countries with subjects that don't count towards the limit, there's probably some potential for even more extreme build there.

Military Honorable Mentions

+20% siege ability costs 30 points. Your armies typically spend more time sieging than fighting, and for this reasonable price, you can make them 20% better at it.

+0.5% yearly army professionalism for 10 points. You can get more up to +2% for 40 points, but this is one of the modifiers where stacking is actually not recommended, as once you hit 100%, it won't do anything (except recover faster from slackening). The best thing about max professionalism is +20% siege ability, which is very nice mid-game, but you don't need to rush it. Taking a level or at most two is good use of points.

These seem really powerful, but the cost is just too high.

Siberian Frontier for 200 points. This is a great ability, but it's priced very high, and you want to take it early (in 2x cost slot) so it's really 400 point of your 800 very easy budget. To make it worth the cost you'd need to either start in Americas, or move your capital to Americas. And if you're playing natives, many recently got some speed colonization mechanics anyway.

Immortal ruler trait for 800 point. Immortal 6/6/6 is very tempting, but the cost is too high, so leave it for roleplaying. For 800 points you can get such insane custom ideas, you really won't miss it.

Free Ideas

If you want to fit limited budget of 200 points, you'll need some filler ideas, as you can't take 10 overpowered ideas.

You'll also need to balance your ideas between categories. Weirdly the game checks how many levels you took, not how many points you spent, so level 2 for 3 points and level 2 for 140 points count for the same.

Here are some 0 point ideas suggestion that provide decent value, by category. You can double most of them for 3 or 5 points if you have a few to spare. None of these are game changing, but since it's a free filler, might as well fill it with something useful.


  • +10% governing capacity
  • -5% core creation cost
  • +5% goods produced
  • -5% administrative tech cost
  • -5% minimum autonomy in territories


  • -5% aggressive expansion impact
  • -5% diplomatic annexation cost
  • +5% trade efficiency
  • +5% improve relations
  • +15 vassalization acceptance
  • -5% diplomatic tech cost


  • +5% siege ability
  • +0.5 army tradition
  • +5% infantry combat ability
  • -5% regiment cost
  • -5% military tech cost