Hi all, so like most of you, I've observed the AI collapse due to rebels everywhere. I wanted to describe the current situation (as I understand it) so we can discuss potential options to resolve it: 

Current game mechanics: 

When a player is over the city cap they suffer an influence per turn penalty

With this penalty it is possible for a player's influence per turn to go negative

If a player's influence per turn is negative, it is possible for their total influence to go negative

If a player's total influence goes negative, there is a penalty to stability

If a city stability drops low enough it will spawn rebels 

These rebels travel across the map pillaging - the impact of the rebels is not limited to the player with negative influence

As these rebels are from the leading AI, they are frequently higher tech units that pose a significant threat. 

Current AI behavior:

An AI player (typically the leading AI) will go well over the city cap by conquering a neighbor or independent peoples

The AI player will respond to the drop in stability by attempting to place large numbers of commons quarters and/or garrisons (often commons quarters with no adjacency)

These measures are insufficient, leading to the AI empire collapsing.

This collapse of the leading AI spawns rebels that hinder all other players 

If the human player has played sensibly, they can 'win by default' as their leading competition implodes 

Possible solutions:

1. Change the AI behavior to match the mechanic

2. Change the influence and/or city cap mechanics (and have the AI work correctly with the new mechanic)

3. Change the quality and/or behavior of rebels to lessen the impact of rebels

1. Change the AI behavior:

Have the AI liberate cities/pillage city centers to manage influence and prevent empire collapse (in the same way as the player does)

2. Change the mechanics:

Lots of options here, my personal preference is that total influence should not go negative. Instead the penalty should be a loss of money and science if total influence is zero. This will stall out a snowball without causing a collapse.  

3. Change the quality or behavior of rebels

Possibly the simplest fix is to have rebels be city levy quality instead of military units

Prevent rebels from pillaging - have them find an empty territory to found their own city

Be able to gift rebels an outpost like other independent people

Dayvit78 wrote:

Thank you for detailing the chain of events that leads to this common problem.

I would like to recommend something that fits in your second solution: allow people and AI to demote a city to an outpost. This way when the AI is over the city cap, they can simply demote one of their cities. Another option would be to make it cheap to merge cities - again so the AI has an option to reduce their number of cities.

Another way would be to add more events or opportunities to increase city cap. I actually like the city cap the way it is since to me it's one of the differentiators from Civ's city spam. It's not fun to manage 100 cities, so people may feel constrained by the limit but it is preventing that tedium.

But I think you're right that the best option would be to teach the AI to not lose influence.

1. You can already liberate cities. It's not the same thing as demoting cities to outposts, but it serves the same purpose. 

2. City merging costs should definitely be lowered.

isle9 wrote:

1. You can already liberate cities. It's not the same thing as demoting cities to outposts, but it serves the same purpose. 

In this case, it falls under his recommendation that the AI learns how to manage it better. Don't build a hundred common quarters. Liberate cities.

To agree with isle9, the city merging cost is currently too high. There's already (in my opinion) enough of a deterrent to merging cities with the various stability (luxuries etc are one per city) and food issues (food scaling means merged cities grow slower or even starve).

And to agree with Dayvit78, the AI should be modified to meet the current game rules. 

That's great to hear the feedback. Maybe it might be easier to have the AI trigger on influence (either per turn or total) instead of city cap? It's quite possible to be over the city cap by 2-3 cities if you're generating enough influence. 

Look forward to see how you get on, I'm enjoying the game and I'm confident it will only continue to improve!

I feel like "AI implodes even on highest difficulties and stops playing the game halfway through, deserting whole continents to roaming rebels and nothing else" should probably be a bit more of an urgent issue than "we'll consider it"

Merging cities is very poor game design right now. The time when you want to do it is when you have lowered or even negative influence gain, it's completely contradictory. I think a better solution would be to have merging cities be done by a national project one of the cities that essentially was the production cost of all the infrastructure you are doubling, maybe a bit more. 

I'm not seeing empires collapsing to low stability in my games, literally ever (HK difficulty). Which map settings are you guys playing on? I usually get a couple of continents, no new world and 40% land. Maybe the AI is not collapsing in my games because that's not enough land for them to get so many cities.

JNR13 wrote:

I feel like "AI implodes even on highest difficulties and stops playing the game halfway through, deserting whole continents to roaming rebels and nothing else" should probably be a bit more of an urgent issue than "we'll consider it"

I think there's a misunderstanding here. We are working on better City Cap management for the AI. The design team will discuss the price of City Merge, hopefully quite soon. Sorry if that wasn't clear enough.

dongliz wrote:

That's great to hear the feedback. Maybe it might be easier to have the AI trigger on influence (either per turn or total) instead of city cap? It's quite possible to be over the city cap by 2-3 cities if you're generating enough influence.

Indeed, good point. We are experimenting with a bit of both (taking into account the share of our influence production swallowed up each turn by the city cap upkeep + how long have we been with too many cities).

Please DONT fix this.

It is a brilliant implementation of the Rise and Fall of empires. An empire rises to great heights, overstretches and then has to divert all its resources to keeping the population happy. And eventually gets overrun by rebels and barbarians. This way, the initial era's don't lock the dominant powers for the rest of the game, but the balance becomes very dynamic. I had great empires fall and one city empires become a major power. Great! At the same time, it can still be competing for the title of greatest empire with the fame they collected earlier. Quite realistic and also fun because the game is not lost when you have a runaway AI, and you can still come back by scoring fame in every era.

If devs would have intended it this way it would have been a great implementation.

Yes I have this behaviour in most of my games. But in most cases I still had to work very hard to overcome their fame score, even after collapsing. Especially if they toke over another continent.  Obviously I don't consider it a bug or critical gap. I like it the map is not static and that they stop snowballing without me having to conquer the world.