AI devoting too many units to fight hostile city-states

[Bison]

Hello everyone! Little feedback about the AI and city states.

Problem:
I've noticed in two games that when the AI is at war, and there's a nearby hostile city state, that the AI moves his entire army to beat up on the CS, leaving a subpar force to defend or attack, often neglecting the rest of the war completely. I've had this happen in my 2 recent games.

In this game, Korea asked me to do a joint war against Russia and they had a defensive pact with the Zulus. The Zulus were a massive force, conquered his whole continent and had 3 times mine and korea's military power. Anyway, the war was basically a stalemate for 30 turns, with Russia killing some units from Korea until I moved my force to help, and the Zulus was NOWHERE to be seen (warscore 0 or 2 against korea). Towards the end of the war I send a spy to a city state and that's where I find his whole army: the city state at full health while he had his army surrounding the CS. Maybe he had trouble moving siege in due to the sheer amount of units, idk, couldn't get a better picture. He didn't capture the city state for another 20 turns, after the war was over.



The point is he had enough of an army to dominate the world at that point, he could've helped Russia and take some of Korea's cities, beat me up and make me show him some respect, but he instead chose to do nothing. In the end he was out-teched and lost to my diplo victory, with korea a little behind on the culture victory. Had he actually used his army at that point the game would've gone much differently.

In another game I played against the Celts it was the same deal; she declares war on me with like 4 attacking ships, but I have an allied city state near her and she just moves her whole army to beat it. For the next 15 turns I move all my army against her poorly defended cities and just raze them and she capitulates.


Solution:
I'm thinking AIs should only use 10 units tops, or maybe 20% of their supply, when trying to deal with a hostile CS, not their whole army. They need to always stay prepared against the army of a rival civ reaching them. From what I've seen they're giving higher priority to a CS because it's closer to their capital, but a CS can do jack squat to them compared to what a player can do.
Also I believe the amount of units is preventing them from properly moving siege engines to hit the city.

Thoughts?

 

[hokath]

I saw something similar recently, though nowhere near this extreme.

 

[andersw]

Yeah thats some difficult stuff to code descision making for an AI but I agree, use less stuff vs CS.
Otoh I see CS getting taken over fast so I wonder what was happening in your game, zulu should roll a CS fairly swift.
Were he at peace with Inca, siam and egypt during the war? cheesy archers on mountains are rough for the AI.

 

[looorg]

Am I missing something or are four Impi to much to send vs a city-state? I assume there a few more tho inside the fog of war. But they don't appear to have brought much artillery. They can't even encircle the city as it is. But I don't really find this very odd. Go in heavy and hard and crush them quickly. Makes sense.

Does Zulu have open borders with Russia? Otherwise that explains why he hasn't come charging down towards Korea. He might not be able to reach Korea by land or sea due to it. He might not be able to make it to the other continent either.

Sure the AI target picking might sometimes be a bit weird. They seem to go for weakest targets first. Which is why you tend to see them run back and forth and so on. A city-state is then weaker then a CIV. But it could also just be that it's closer.

Also they (Malacca) are at war since Korea is their master and dragged them into it. It's also very close to the Zulu capital. So considering that Malacca is probably surrounded by Zulu lands, possibly also a bit of Russia, it makes sense to take them out before you march down for Korea. From the Zulu perspective.

From just the tooltip and the map I don't really see what else he is supposed to do here. He (Shaka) is at war with Sweden, Denmark and Korea plus about eight different city-states. I assume most of the those are allies of the three mentioned civs.

I assume Sweden (the player) have more or less crippled Denmark (3 cities left?) and/or have them as their vassal. They are on a different continent. Korea is beyond Russia from the Zulu perspective so it might not be an easy trip or even possible to reach without going way into the ocean and then down. Or march across Russia.

From the rest of the picture I am left wondering why he isn't also at war with the Inca, I assume the defensive pact came after the war or something. Russia is to large to be a vassal from the map, but you never know -- the ai do crazy volunteer vassalage some times. So they are at war with Sweden at least. but not sure if they are at war with Korea.

The Zulu appears to have crushed or nearly crushed Siam. Egypt doesn't appear to be doing great either.

For SHaka I assume he will come eventually, after he smacked down the entire continent and then the next continent is one the menu.

 

[Bison]

Yeah thats some difficult stuff to code descision making for an AI but I agree, use less stuff vs CS.
Otoh I see CS getting taken over fast so I wonder what was happening in your game, zulu should roll a CS fairly swift.
Were he at peace with Inca, siam and egypt during the war? cheesy archers on mountains are rough for the AI.

I'm not sure, they move their melee units and try going for a barricade, but they were not actually hitting it for much. All I could see was the melee units moving back and forth from the city during his turns.
Zulu was at war with Siam but finished conquering him like 5 turns in. Inca was fighting egypt and conquering his cities; in a later war the Zulu stepped in and fought the inca and gave the last city back to Egypt. In this war, for 30 turns, he didn't really do anything though.

Am I missing something or are four Impi to much to send vs a city-state? I assume there a few more tho inside the fog of war. But they don't appear to have brought much artillery. They can't even encircle the city as it is. But I don't really find this very odd. Go in heavy and hard and crush them quickly. Makes sense.

Does Zulu have open borders with Russia? Otherwise that explains why he hasn't come charging down towards Korea. He might not be able to reach Korea by land or sea due to it. He might not be able to make it to the other continent either.

Sure the AI target picking might sometimes be a bit weird. They seem to go for weakest targets first. Which is why you tend to see them run back and forth and so on. A city-state is then weaker then a CIV. But it could also just be that it's closer.

Also they (Malacca) are at war since Korea is their master and dragged them into it. It's also very close to the Zulu capital. So considering that Malacca is probably surrounded by Zulu lands, possibly also a bit of Russia, it makes sense to take them out before you march down for Korea. From the Zulu perspective.

From just the tooltip and the map I don't really see what else he is supposed to do here. He (Shaka) is at war with Sweden, Denmark and Korea plus about eight different city-states. I assume most of the those are allies of the three mentioned civs.

I assume Sweden (the player) have more or less crippled Denmark (3 cities left?) and/or have them as their vassal. They are on a different continent. Korea is beyond Russia from the Zulu perspective so it might not be an easy trip or even possible to reach without going way into the ocean and then down. Or march across Russia.

From the rest of the picture I am left wondering why he isn't also at war with the Inca, I assume the defensive pact came after the war or something. Russia is to large to be a vassal from the map, but you never know -- the ai do crazy volunteer vassalage some times. So they are at war with Sweden at least. but not sure if they are at war with Korea.

The Zulu appears to have crushed or nearly crushed Siam. Egypt doesn't appear to be doing great either.

For SHaka I assume he will come eventually, after he smacked down the entire continent and then the next continent is one the menu.

The main problem is that he wasted a huge deal of time around the city state not doing anything to it, and without any presence on the map.
And sure it would be fine if they could take the CS down easily, but in this game and the previous one they have a lot of trouble getting its hp down. Might be some issue with the siege pathing.
Can't tell you if he had open borders with russia but probably yes, AI loves open borders and they were pretty friendly up to that point.

But like mentioned, perhaps it would be better to just assign 10 units to kill the CS's units so they stop bothering you and use the rest of your army to do something more productive.

 

[andersw]

I'm not sure, they move their melee units and try going for a barricade, but they were not actually hitting it for much. All I could see was the melee units moving back and forth from the city during his turns.
Zulu was at war with Siam but finished conquering him like 5 turns in. Inca was fighting egypt and conquering his cities; in a later war the Zulu stepped in and fought the inca and gave the last city back to Egypt. In this war, for 30 turns, he didn't really do anything though.

I think the combined wars are the reason.
I see more and more that the AI struggles in multiple front war, over aggressive play (which is good enough vs a single enemy) retreating injured units to places where they cant heal up.
The AI doesnt ignore a front like we do and instead sends units in every direction so when things go bad it really crumbles.
Could also be that Siam was an easy pushover and that he then got stuck in the incan mountains, cheesy archers sitting on mountains are hard enough for human player I dont expect the AI to do better, war vs Inca can be a serious pain, add that zulu prefer to spam melee units.

 

[myclan]

AI doesn’t have strategy, nor tactics, that’s why the easiest way to win a deity game is conquering.
There are few things we can do to make AI more clever, but another way is make CS weaker by reducing city strength like wall/castle forbidden. Players can conquer a CS very easily anyway.

 

[Bison]

I think the combined wars are the reason.
I see more and more that the AI struggles in multiple front war, over aggressive play (which is good enough vs a single enemy) retreating injured units to places where they cant heal up.
The AI doesnt ignore a front like we do and instead sends units in every direction so when things go bad it really crumbles.
Could also be that Siam was an easy pushover and that he then got stuck in the incan mountains, cheesy archers sitting on mountains are hard enough for human player I dont expect the AI to do better, war vs Inca can be a serious pain, add that zulu prefer to spam melee units.

He wasn't at war with the Inca. Like I said, he went to war with the inca later on (after having finally conquered malacca), and was pretty effective at it. If I wasn't there to defend with newely researched tanks he'd have taken the incan cities (formerly egypt's) by land and sea. Unfortunately he was just outteched at that point, but still had massive military power (450).
Here's some other pictures from that game.
Also note the Ishbaya from 4uc giving +100% defense modifier to the field gun, which should have no terrain bonus, I guess that's a bug?









Other than the massive blunder at that point with the cs, which cost him the game basically, he did do a good job.

 

[azum4roll]

No Defensive Terrain Bonuses doesn't include improvements.

 

[Bison]

No Defensive Terrain Bonuses doesn't include improvements.

Oh wow nice to know; maybe that distinction could be made clearer?