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EU4 - Development Diary - 26th of March 2019

Good day and welcome to this week's Dev Diary for EUIV. I'm sure it comes at an unforgivable late hour for many, but I have not long returned from a short trip to Lithuania. The country is a bit smaller than I remember, but Vilnius was a delightful place to spend the long weekend.

I'm returning as forewarned by last week's Dev Diary to talk about ambitions for game mechanics in the upcoming European Expansion, slated for Q4 this year. As neondt has been discussing with maps and missions, I too will be sharing thoughts and ideas that we have regarding certain game mechanics. What is mentioned here are not changes that are currently in the game, nor are they promises of things to come, but more to share our thought process and ideas we have for the upcoming expansion and update.

During the large end of year Dev Diary I mentioned various wishlist items that we would like to tackle in EUIV and on the list, right at the top, which with a degree of imagination is in bold, flashing colours and on fire, is that the current state of mercenaries in the game is long overdue for a shakeup. That's what we're here to talk about today.

Firstly, why are we even talking about Mercenaries at all? Well Europa Universalis is a game about building Empires, and the business end of your stick are your armies. While regular armies are cost-effective for ducats, they can and likely will run dry of manpower in prolonged wars. Mercenaries exist for you to supplement your fighting force at an inflated ducat cost, allowing you to extend your own fighting capacity so long as your coffers can handle it. In the past, there was a limit to how many mercenaries were available to hire due to a 1% daily chance of mercs becoming available. This was removed in the interest of expunging the random element to available armies, and now your number of available mercs are tied to your forcelimit. Mechanically it's all very functional, but not without its issues

40-0-40 mercs.jpg


Look familiar? Once one's economy is in good shape, the go-to for a nation is to flesh out their army mercenary infantry and, should they feel decadent, mercenary artillery and keep that as a permanent solution for all aspects of warfare. They are the ultimate siege weapon due to reinforcing without need for manpower, so attrition is seldom a concern, while also being an entirely effective battle force as they take your nation's bonuses to battle, and any losses are very quickly recovered in exchange for money.

Even in the event of your mercenary armies being wiped out, so long as you have the money, you are able to swiftly recruit as far as your force limit allows courtesy of their quick recruitment time, and within a few months, your armies march once more with renewed vigour and no impact on your manpower pool.

Now to its credit, the way mercenaries work currently allows for a nation to always keep their momentum going. It can be no fun to simply sit on your thumb for manpower to recover for a war you want to fight if you find no other options available to you, and I'm sure most of us have found ourselves in a war which would have been all but lost if a few loans and an eager band of mercenaries had not been available to save the day.

So what are our thoughts from here? Well, there is certainly no end to the balance tweaking that could be done here, as the variables involved are plenty and could be adjusted: rising cost of mercs, restricting their availability, perhaps reigning in how easily they adapt to all of your country's military traditions, fostered for centuries, within a few days. This could be done, and indeed it wasn't too long ago that we did increase mercenary costs across the board, but I believe the solution should be grander in ambition, to be fitting for the gravity of the Expansion we're planning for this year.

@Groogy and I have hashed out thoughts on mercs with very much a "back to the drawing board" approach on the system. What has become more and more apparent is that the system as it exists is ripe for a full makeover.

The European Expansion and its update will, in all likelihood, feature a completely different mercenary mechanic from what we know today. We have established several key aspects of how we want to handle mercenaries:

  • We still want them to exist as a way to supplement one's army strength for ducats.
  • Province-level recruitment will probably have to go. Reducing click-fatigue while we're at it should be a priority.
  • The system should respect geopolitics: Mercs in India should be functionally different from Germanic ones.
  • Mercs must be finite to some degree. As an example, a prolonged 30 years war should drain Central Europe of available mercenaries, and said merc units should find themselves no longer able to reinforce.
  • Player involvement in the system must be greater than it is today
  • Late game multiplayer must be diversified from all out merc-on-merc warfare.
  • The system should be robust, feel alive, and enjoyable

In addition to this, we want to make the fundamental changes to the merc system part of the update. All players who get the planned Q4 update should enjoy a new merc system to explore.

The Dev Diary may end up raising more questions than it answers regarding mercs, but this is not the last we'll be talking on the matter. This and various other DDs to follow are to shed light on our internal thoughts regarding development, rather than showing off what we have added to the game. I'm sure you're growing tired of hearing it by now, but we continue to iron out tech-debt issues (which really deserve a dev diary of their own) and gearing ourselves up for developing this large European Expansion.

What are your thoughts on the existing mercenary system and what would you like to see in a new update? Let us know in this thread, and we'll be back next week to talk more on our plans for the upcoming Q4 Expansion and Update
 
While reading the DD and pondering over the mercenary availability problem, I thought of something...

What if the mercenary pool for a country was based on its occupied provinces, but with a modifier linked to... devastation? Meaning the more your country (or the occupied provinces you have) are devastated, the more mercenary you can field.

Just an idea like that.
 
Would it be possible to have a system where the number of merc regiments available is dynamically increased or decreased depending on how many wars are going on and thus how many people are interested in hiring mercenaries? I.E a supply and demand system of sorts perhaps?
 
Some scatter-shot ideas: ;)


If we're attributing mercenaries to a particular region, perhaps a geopolitical element can be included.

For example, if you are the primary nation for a particular culture, mercenaries of that culture are a little cheaper/more loyal; however, if you are at war with the nation of your hired mercenary's culture (or if that culture is fighting for independence), they will be more expensive and/or flip to the winning side. Friendly relations with Hesse can help you hire Hessian mercenaries.

Maybe mercenary companies could be treated as localized estates (i.e. if you conquer Switzerland you have the Swiss mercenaries estate)?

What about naval mercenaries as a way to engage in exploration, army tranport, and/or privateering without using more sailor manpower?

Many of the unit models are so well done that I would rather vassalize a nation than conquer them; what if mercenaries hired from a region maintained the unit models of their culture regardless of which nation hired them?

As an additional money-sink for nations that rely on mercenaries, what about an option (limited like war taxes) to pay to replenish mercenary morale/numbers?

If you cancel a mercenary army or can't pay them during war, they can flip sides in a war.

Mercenary armies take the lion share of loot during sieges.

Mercenary bands are more likely to rise as revolt tags or rebels in nations that rely on them (national disaster); they will travel from province to province spreading devastation and even reducing trade (they get a slice of pie like pirates or something).

Would-be usurpers spawn as a mercenary army that nations can enter into diplomacy with to support with cash, or even ally and join into war with. For example, Jacobin forces can be hosted in France and supported to overthrow current British monarch, or the British could support their own invasion with William of Orange to avoid slipping back into Catholicism...?

Trade companies and colonies can hire local mercenaries/natives independent of their mother nation.

Two opposing mercenary armies will be more likely to skirmish and retreat sooner in battle instead of committing to the last man or toward the last bit or morale.

Mercenary generals generate traits like other generals and generally become more expensive to hire as a result.

...


I hope there is something of use in here. :D
 
The main change I'd like to see with mercenaries is limiting their numbers in some way so that you can drain a nation's ability to wage war without driving it all the way to bankruptcy. This would increase the strategic importance of preserving troops, and would make defensive warfare more interesting since you could use terrain bonuses to grind a superior foe down. In the current version of EU4 it's basically impossible to win against a country with a superior economy since they can fling an endless supply of golden goons that will eventually break you through sheer numbers. There's also a problem of easy loans allowing excessive overleveraging followed by truce-locked chain bankruptcies, but one problem at a time I guess.

Transferring Imperator's mercs system would probably solve EU4's merc problem. While you're at it, you could transfer in Imperator's fort system and alliance system to improve the game further.
I like the first part of what you said. I disagree with a stronger economy always winning though. The AI is in desperate need of fixing. It's bad, like, really bad. I've posted a number of screenshots from VH games outnumbered 4:1 behind in mil tech, no mil ideas, standing next to massive stacks of enemy AI troops sieging down their capital. In Florry's latest game he trapped a good portion of the HRE on a Danish island and beat 200k enemies including Austria with 20k. You can attack Muscovy as Norway and just siege them down as it takes a literal year for them to reach Scandinavia while they don't bother defending their homeland or engaging you.

Bankruptcy seems to just be a planned feature of most campaigns now thanks in part to the monumentally stupid idea that was territory corruption. The game would be practically unplayable for many starts if bankruptcy weren't relatively accessible.
 
Each country could have an 'Overall Manpower Pool' that's split into three; manpower, trained manpower, mercenaries.

Manpower is normal manpower.
Trained manpower is men who have been trained and disbanded. They can be rehired for less and take less time to retrain. It means players could train men when they have money and then disband them to save maintenance cost.
Mercenaries do exactly what it says on the tin.
 
@DDRJake

Mercenaries could be recruited in states instead of provinces. The state’s majority culture enables the type of mercenary.

The amount of mercenaries that exist would be related to the overall military development of the state.

This way, highly populated areas which historically had a lot of mercenaries like northern Italy and western Germany would be depended upon more.

Mercenary cost could be related to how many provinces you own in that state and how far away the state is from your capital. A new edict that lowers mercenary cost could be introduced as well.

To show how war and veterancy created more mercenaries, perhaps have high devestation spawn mercenaries faster. This would be an abstract representation on how devastation caused by frequent fighting made people look for money in conflict as well as and outlet for personal revenge.
 
Mercs shouldn't decrease professionalism, that doesn't make much sense to me. Mercs are literally professional soldiers! For sake of balance, I suppose it's okay...
 
Cheers for the DD DDRJake :). Giving mercs a nip and a tuck sounds good. One of the things that's always got me about mercs is that my understanding (and it's sketchy, so shoot me down in flames if I'm wrong) is that mercenaries became relatively less important over the EU4 period, rather than more important, such that the gameplay mechanic ran against the trend of history (where early EU4 involves careful and scarce mercenary use, and late EU4 involves the domestic population living a life of cream on buns while some poor sods are paid to do the nation's fighting for them). Such that mercenaries as the proportion of a nation's forces during a war declined, rather than increased (as a general trend) over time. If the cost (or availability) of mercenaries relative to professional soldiers increased over time, then mercenaries could still be an important tool late-game, but also be a more important tool early on? Please ignore if silly :).

to be fitting for the gravity of the Expansion we're planning for this year.

Issac Newton EU4 themed expansion incoming! :eek:
 
Instead of mercenaries having all of their employer's bonuses, give mercenaries 'Adaption', which accumulates at 1% per month to a maximum of 50%. This adaption gives them that percentage of employer's bonuses, and can be reduced through replacements. Also mercenaries should have a base discipline bonus of their own.

With regional mercenary pools, limited spill over from adjacent regions should be possible from a near full region to a near empty region.
 
I am skeptical that merc systems need a great rework because a certain part of the playerbase struggles with dealing with AI Ottomans (this is frankly what most criticisms boil down to, that AIs don't lie down and die after you win the first few engagements). And I think you've received a lot of feedback from great MP players in this thread regarding why your assumptions are somewhat flawed in that arena as well. Unfortunately most of them are reflexively downvoted without any engagement with their arguments.

But since the choice has been made, here is a question to reflect upon: professionalism was a fairly extensive mechanic implemented to make mercenary recruitment have a large apparent tradeoff. However, for the vast majority of purposes, in MP and SP, this mechanic has failed - at best, most players interaction with the mechanic involve maximizing slackens while being between 0-5 professionalism, or snowballing already privileged starts that have the resources / time to invest in military strength. And arguably, for the latter, this is only because of a defective AI that greatly prioritizes siege racing over forcing even battles, so most wars are decided with less than 5 battles fought.

Your homework is this: why did this mechanic fail to achieve what you desired? And how does introducing vastly more buttons avoid the same problems?

If you cannot understand the problems, you will not design effective solutions.
 
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Proposal: Have the Mercenary Pool based on the manpower pools of friendly nations.

So when you want mercs, the recruit button is pulling from the actual manpower of nations in the game. If everyone hates you, no mercs will work for you. If war has drained the manpower of everyone, no mercs will be available.

If you're a nation planning to wage lengthy wars, it becomes much more valuable to maintain good relations with other nations to keep your merc pool as large as possible. You could also sabotage your enemy's relations to reduce their merc pool.

If you're a nation with a full manpower pool, you'll now be getting -paid- for whatever % of your pool you want to make available as mercs. So instead of full manpower being a waste of resources, it can become an opportunity to improve/recover your economy while providing mercs to your friends. To make it more likely that mercs are available, I'd have an "overflow" for manpower, so that say up to a year's worth of manpower over 100% is stored just for the merc pool.

It'd probably be necessary to increase overall manpower to balance the removal of magical merc spawning, but that's a pretty straightforward thing to balance - it's one number.

With this system, the game would no longer have mercs magically appearing. Nations with full manpower would gain a benefit from it. Lengthy wars would have a real, tangible gameplay impact. Diplomacy would be more important. Best of all, it's a pretty straightforward concept, and doesn't add a bunch of new numbers, modifiers or UI panels.

I really like the idea of relationships with other nations reflecting the availability of mercs - especially as I think that would work really well to reflect hiring local forces with trade companies. And the idea of the manpower coming from a real source already in game.
But.... that is kind of what conditori do.

A thought; why not tie mercs to, instead of the geographic region bit thrown around (which would make France unlikely to hire German mercs which is odd) tie them to trade nodes? And perhaps have the quantity of trade power in a node determine how many mercs can be hired there and have countries with trade power there benefit from hired mercs? For example, this would mean that end nodes like Venice would have high merc counts (which is historically pretty accurate) and that hiring mercs would help the economy of those with power there; IE venice. Mercs essentially bring in money from foreign powers.

And restrict where you can buy mercs to where you have trade power and have hiring mercs from that region penalize your trade power there, so you're effectively paying trade power for mercs? That can help curb the "build massive stacks and ignore everything else" while making sure that merc amounts are variable and reflect the relationship of mercs to economies. It would also mean devastation would lower the merc pool :)

I really like this idea as it is kind of simple, although I wonder whether it would be hard to avoid this just enabling a continuation of never ending mercs. Perhaps if the availability of mercs in a tradenode was reduced over time? Possibly linked to the institution mechanic?
 
My first thought would be to have each Region have a mercenary pool based on local manpower. That way manpower development would be more powerful, and the mechanic would be sensible. Perhaps have over-maximum manpower go to the merc pool as well. You could even introduce a "mercenary manpower" modifier to certain countries.

I'm personally skeptical about introducing something entirely different at this point of time, however.
 
Whats about a Regional Mercenary Pool, with own Modifiers and Mercanary Manpower, which you can Recruit from if youre Capital is located in the Region or if you have something like at least 20% of the Develepment of the Region.
 
Something I'd find an interesting point would be if Mercs available were tied to deleted regiments. An odd idea, but in that kind of "makes sense" idea. Most Mercs getting their training from regular armies as happens. And when the armies step down from a war footing... well you got a bunch of people with military skills who are looking for a paycheck.

It'd probably require an AI change to make work as the AI just tends to sit on their armies on total, at least that I've seen. Probably just an insane pipe dream but I'd find it kind of a cool. Like Hesse goes to war in the HRE, bloated it's military out to max, and then cut back to feed the coffers after the war. Well, where did the military go? Suddenly there in the Recruitment pool is 5 units of Hessian Mercenaries (with their tech, traditions, etc), looking for a contract. And France is hiring Hessian Mercs for its war with Burgundy. And after that war, cutting back and there's now French and Hessian Mercs freed up that end up serving in the Portuguese defense of Cueta, etc.

Problem is I suppose, I never see the AI disband units, so the only one who'd be sending mercs out there is the player(s). Could be an interesting dynamic that way in multiplayer.
 
I agree with limiting mercs. Like others, I think there should be mercenary manpower pools, and you can raise mercenaries from any region where you have diplomatic range, though perhaps mercs can only operate a certain distance from their home region (so you can't use Indian mercs to fight a war in Europe).

When mercenary manpower pools are high, mercenaries should be very cheap. As the pool depletes they should become exponentially more expensive. In this way mercenaries should never totally deplete, but they might get so expensive as to be utterly impractical, hence creating a kind of supply and demand based pricing.

Sources of merc manpower could be :
* static amount generated from all province manpower.
* desertions from attrition and battle.
* stack wiped armies.
* defeated rebels (rebels might also draw on merc manpower)
* revolt risk might shift manpower from your pool to the merc pool
* decommissioned armies
* overflow if your manpower pool is full.

All of the above could be modified by army professionalism. Countries with high professionalism should generate far less mercs. EG countries with a disciplined professional army won't see nearly as many desertions.

The end result should be that peaceful politically unified empires, like the Ottomans or Ming should generate far less mercenaries than fractious regions like the HRE or India. Instead unified large empires should be able to solely depend on manpower. Small wealthy countries like the Dutch or Venice will be able to draw on the mercenary manpower generated by neighbouring regions. However lengthy large-scale protracted war will drain this pool rendering warfare for even these wealthy republics financially ruinous as costs climb and the continent empties of military age men.