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HOI4 Dev Diary - Custom Gameplay Rules

Hi everyone! Most of the team is now back after summer so it’s time to spin up the ‘ol diary machine again. Today we are going to be talking about something we have been thinking about adding for a really long time: Custom Gameplay Rules.

First off, let me explain why we are doing this - HOI4 is a game people play in a lot of different ways. Single player, multiplayer, achievement runs, casual relaxing and various other. There is also a big split between people who play “historically” vs people who don’t (it’s around 50/50). A lot of stuff that adds fun and a sense of power in singleplayer are not very balanced for organized competitive multiplayer so organizing these games can be challenging, often including long rulesets and policing by the server host. I personally think a big reason competitive multiplayer isn’t as common (about 6% of MP games are competitive) is because it’s so much harder to set them up when they require reading rulesets, which become fragile when the game itself isn’t enforcing them.
When it comes to single player, players often ask for ways to tailor how they play. For example; some will use console commands to switch nations to set them on certain paths to match their long term plans for the scenario they want to play out etc, but it’s not exactly beginner-friendly, and isn’t possible to do in multiplayer either. So looking at all of these things we decided that we needed to support different rulesets and let players affect how the ai did things in more detail.

So, enter Custom Game Rules. This is a new setting you can do before you start your game, and includes the old buff sliders for majors as well:
main.jpg


It’s possible to store and load presets if you have a couple of prefered profiles you run (say single player and multiplayer?). We have tried to make rules as moddable as possible although when they directly impact hard-coded gameplay mechanics we need to make sure we have worked them in first. We’ll go over the modding aspects towards the end!

So what kind of stuff can you do? We haven’t fully finalized it all, but let’s go through what we got. I am sure people will have tons of suggestions in the comments too ;)

All diplomatic actions have the possibility for rules. So we can restrict or ease up how things work. This is particularly good when you want to tie focus trees into it. The new British tree has a lot of interaction with releasable nations, so this also lets us manage that from scripts and avoid exploits and weird situations (such as the player going down the ‘empire’ path, and yet releasing every colony they own).

release.jpg


rule.jpg


Covert actions are also included here, so you can for example restrict coups and such only to AI nations (a common rule in our own MP sessions).
covert.jpg


There are also other bits and pieces like being able to limit fort levels constructable, limiting paratroopers and such we are playing around with. Other things rules we see people use a lot are for example limiting war declares before certain dates etc. I expect we will be presenting a full listing of options later when we stream stuff closer to release.

You can also affect how you want the AI to act. Mostly this means it will be preferring certain choices and switching to alternate plans. If you want to tailor-make your game experience this is a great way of ensuring certain (a)historical outcomes being attempted by the AI no matter your settings.
ai_ger.jpg


For most there are options for ideology while some like Manchukuo are more relevant to its situation:
man.jpg


Some settings, like this particular one, are dependent on DLC, so without Waking the Tiger (which comes with that focus tree) the option simply won't be there. Otherwise the whole custom rules system is part of the free update and is for sure something we will be building on in the future.

Rules will generally turn off achievements, but its possible to set it by rule so if we introduce something we feel is ok in both it will still work.

Modding
So, when we started with this we realized we couldn't support every tiny rule some MP groups were using and instead we’ve tried to make it as easy as possible to mod things in. It’s my hope that some cool ruleset mods will be developed specifically for competitive multiplayer and the like in the modding workshop. Very popular options may even see inclusion in the base game in the future, who knows :) I expect some of the big mods will want to include custom rules as well for their players.

Rule definitions look like this:
mod1.jpg


They can then be checked from triggers from say the tech tree, focus tree, events etc and in other places we have added support for triggers. Example:
mod2.jpg


Diplo actions are a little special. They each get two possible triggers. This way you can turn on or off the standard game checks (like checks against world tension from game code) with the _TRIGGER_OVERRIDES_GAME. For your own rule checks you use the _ENABLE_TRIGGER for the specific action and the scope will contain the target nation as well so you can do nation specific rules.
This is what the triggers for Guarantees look like:
Screenshot_1.jpg


That’s it! Tune in next week to find out more about what we are up to with Man the Guns and the 1.6 ‘Ironclad’ update.
 
Will there possibly in the future be the option to set AI Germany to go monarchist in achievement mode, or Hungary? This is just an idea but maybe it there could be a limit to how many countries you can have going different paths at once in achievement mode. Great Dev Diary can't wait for the update and DLC this looks like the biggest update and DLC for HOI IV yet! (I appreciate all the work you guys are doing and thank you all for it!)
 
Rules will generally turn off achievements, but its possible to set it by rule so if we introduce something we feel is ok in both it will still work.
Pleasepleaseplease allow us to at least select one custom AI Behavior choice and still allow achievements. I'm not talking about tailoring the whole game setup to make life super-easy, just the option to make sure one opponent does something fun rather than rely completely on RNG to get that one in a hundred games where AI Germany actually goes for Kaiser, etc.

Since we're currently allowed to pursue achievements with 'ahistorical' AI focus active, being able to dictate one directly rather than performing a hundred restarts, this wouldn't break current design paradigms wrt. achievements, only make the process far less painful and time-consuming (and yes, I *have* done this. Several times. AI Kaiser is best Kaiser.).

As an example - currently, the only feasible way to stay a neutral Austria-Hungary is to have AI Germany go Kaiser (as otherwise they'll pick the 'Align Hungary' focus which will turn Austria-Hungary fascist no matter what they do, and it can only be stopped by destroying Germany before they pick the focus). For this reason alone, I'd love the option to allow at least one erratic behavior in achievement mode.

Alternately, fix that particular German focus somehow (if Hungary has become Austria-Hungary, no can do / if Austria-Hungary at war with Germany, no can do / if Germany is dead, disable constant influence). I'm very pro-Kaiser in HoI4 these days. :p
 
This is really cool for multiplayer. Now, for single player, I wish there was an option to make ahistorical even more ahistorical than it is now, like the chance of Germany opposing Hitler is very low, I wish there was an option to make it like 50/50. Not only Germany's ahistorical path but to all countries. Randomness is fun, pre-setting it isn't that fun.
And pleeease add a button to our army to prevent them from going to the sea. I've ragequit so many games where 30 divisions of mine take a weird path across the sea and disappear from the game.
 
Any chance of an option to buff one or other side in the Spanish Civil War?

(This not at all induced by having to rerun multiple hands-off games to test balance because the Nationalists went and lost it)
 
Hi everyone! Most of the team is now back after summer so it’s time to spin up the ‘ol diary machine again. Today we are going to be talking about something we have been thinking about adding for a really long time: Custom Gameplay Rules.

First off, let me explain why we are doing this - HOI4 is a game people play in a lot of different ways. Single player, multiplayer, achievement runs, casual relaxing and various other. There is also a big split between people who play “historically” vs people who don’t (it’s around 50/50). A lot of stuff that adds fun and a sense of power in singleplayer are not very balanced for organized competitive multiplayer so organizing these games can be challenging, often including long rulesets and policing by the server host. I personally think a big reason competitive multiplayer isn’t as common (about 6% of MP games are competitive) is because it’s so much harder to set them up when they require reading rulesets, which become fragile when the game itself isn’t enforcing them.
When it comes to single player, players often ask for ways to tailor how they play. For example; some will use console commands to switch nations to set them on certain paths to match their long term plans for the scenario they want to play out etc, but it’s not exactly beginner-friendly, and isn’t possible to do in multiplayer either. So looking at all of these things we decided that we needed to support different rulesets and let players affect how the ai did things in more detail.

So, enter Custom Game Rules. This is a new setting you can do before you start your game, and includes the old buff sliders for majors as well:
View attachment 393772

It’s possible to store and load presets if you have a couple of prefered profiles you run (say single player and multiplayer?). We have tried to make rules as moddable as possible although when they directly impact hard-coded gameplay mechanics we need to make sure we have worked them in first. We’ll go over the modding aspects towards the end!

So what kind of stuff can you do? We haven’t fully finalized it all, but let’s go through what we got. I am sure people will have tons of suggestions in the comments too ;)

All diplomatic actions have the possibility for rules. So we can restrict or ease up how things work. This is particularly good when you want to tie focus trees into it. The new British tree has a lot of interaction with releasable nations, so this also lets us manage that from scripts and avoid exploits and weird situations (such as the player going down the ‘empire’ path, and yet releasing every colony they own).

View attachment 393773

View attachment 393774

Covert actions are also included here, so you can for example restrict coups and such only to AI nations (a common rule in our own MP sessions).
View attachment 393775

There are also other bits and pieces like being able to limit fort levels constructable, limiting paratroopers and such we are playing around with. Other things rules we see people use a lot are for example limiting war declares before certain dates etc. I expect we will be presenting a full listing of options later when we stream stuff closer to release.

You can also affect how you want the AI to act. Mostly this means it will be preferring certain choices and switching to alternate plans. If you want to tailor-make your game experience this is a great way of ensuring certain (a)historical outcomes being attempted by the AI no matter your settings.
View attachment 393776

For most there are options for ideology while some like Manchukuo are more relevant to its situation:
View attachment 393777

Some settings, like this particular one, are dependent on DLC, so without Waking the Tiger (which comes with that focus tree) the option simply won't be there. Otherwise the whole custom rules system is part of the free update and is for sure something we will be building on in the future.

Rules will generally turn off achievements, but its possible to set it by rule so if we introduce something we feel is ok in both it will still work.

Modding
So, when we started with this we realized we couldn't support every tiny rule some MP groups were using and instead we’ve tried to make it as easy as possible to mod things in. It’s my hope that some cool ruleset mods will be developed specifically for competitive multiplayer and the like in the modding workshop. Very popular options may even see inclusion in the base game in the future, who knows :) I expect some of the big mods will want to include custom rules as well for their players.

Rule definitions look like this:
View attachment 393778

They can then be checked from triggers from say the tech tree, focus tree, events etc and in other places we have added support for triggers. Example:
View attachment 393779

Diplo actions are a little special. They each get two possible triggers. This way you can turn on or off the standard game checks (like checks against world tension from game code) with the _TRIGGER_OVERRIDES_GAME. For your own rule checks you use the _ENABLE_TRIGGER for the specific action and the scope will contain the target nation as well so you can do nation specific rules.
This is what the triggers for Guarantees look like:
View attachment 393780

That’s it! Tune in next week to find out more about what we are up to with Man the Guns and the 1.6 ‘Ironclad’ update.
Those two weeks felt more like two months.
Though it was already expected, I sure hoped this DD had a little more spice, but I'll take what I can get, I'm just glad it's back o/
 
This is really cool. Something the game lacked. I am looking forward to the release.

Two things; One: the ability to increase special forces percentage to countries that historically had more marine and airborne divisions than other countries such as the US had 1 mountain, 6 marine and 5 Airborne divisions for a total of 12 out of 97 or 12.37%. That is not easy to get to in cornflakes.
Two: Please do not lose the focus of this iteration to fix the naval engine and add fuel. I worry you will focus on the these cool features and take your eye off the real goals.
 
One step closer to perfection!
 
Lovely! MTG is shaping up to be rather fine!

I'm just wondering again if we might see some quality of life improvements to the launcher, especially the mods tab? In order to select only 'Active mods, or to Search for a mod by a keyword (sometimes they are tricksy and don't have the exact name as their Workshop title!), as alas, I am subscribed to as many mods as there are fully equipped divisions on the Eastern Front. Some kind of additional filtering would be a godsend.

Please, oh merciful Paradox gods, bestow upon us this boon!
 
Really interesting stuff. Though like other achievement hunters I'm wondering what sort of restrictions will be on achievements with the different AI rules. Because while hunting some achievements are made all too easy by the AI doing certain things, others are all but impossible without a specific series of events firing off in a very precise way, leading to dozens upon dozens of resets and start overs just to get it so that Yunnan and the Gangxui Clique accept Nationalist China as their overlord.
 
This is great!

Any chance of seeing a slider or ruleset which allows you to specifically tell nations to do anything except for their historical path i.e. Germany will go democratic or have the glorious return of the Kaiser?

EDIT: also possibly something along the lines of "Anything but Republic" come to think of it
 
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Cheers for the DD Podcat, and the extra info Bratyn/Havebeard :D. These changes look like they'll be pretty good for single-player as well, so not just an MP boon (but tops for MP). Also could come in very handy testing out mods (for example, how does my new NF branch for a Germany that only builds ships go? Now I could set it as a rule and make it super easy to test, and also test it against specific other combinations of paths) :cool:. Also love the moddability, am quite sure there'll be plenty of interesting custom rulesets pop up, as well as big mods like Kaiserreich and BICE having their own custom rules :).

As for a ship pic based around a ruleset...... here's USS Pensacola, one of the USA's first treaty-limited (rules, right? :p) cruisers :D.

0402411.jpg
 
yeah for sure. We have discussed a few of these. I feel like perhaps they might be better as rulesets from the community because there would be A LOT of options and they would only be interesting for specific groups. If you wanted to do this it would be a really quick mod job. Supporting some majors may happen tho if it fits in well.
Breaking my heart :(. I am a vanilla host type of guy.