AI cities (colonization and management)

[momfan]

Vanilla was very poor & heavily bugged. Insecticide is miles better and free of bugs.

...

Also, the decision whether to build a unit or a building needs a revision. I need to insert an emergency situation calculation. Not easy.

One outcome of the AI's attack/defend policy change in Insecticide is that the AI wizard fortress is now rather poorly defended.

In vanilla I could count on hordes of end-stage units (paladins, warlocks etc) and rare/very rare creatures (drakes, djinns, efreets, angels, storm giants) waiting for me in the fortress, so I'd bring my super duper stack. But in Insecticide, they sally forth on the overland map to meet me, which means I can usually just go around them and take the fortress directly.

I'm not sure how finely we can balance defending other cities versus protecting the present city, but clearly defending the fortress should receive top priority. If it's possible, the fortress city should run a different defence routine i.e. if there are strong enemies nearby the garrison units should stay put no matter what, better units should be built, and more powerful monsters summoned.

Otherwise, it's a bit of a letdown when I fight my way through the hordes only to be confronted with a few priests and halberdiers at the fortress itself.

[kyrub]

I'm not sure how finely we can balance defending other cities versus protecting the present city, but clearly defending the fortress should receive top priority. If it's possible, the fortress city should run a different defence routine i.e. if there are strong enemies nearby the garrison units should stay put no matter what, better units should be built, and more powerful monsters summoned.

The fact that the fortress is not well defended stems from the routine that sends away the best soldiers to attack / conquer / defense, from any city. I think I can easily reverse this function to follow the vice-versa for the capital, e.g. only the weekest are sent away.

The problem lies in the fact that the fortress city is often the most developped and it quite often has the summonning circle. The fortress spams the best units, in biggest quantities. For a large part of the early-mid game, it is the engine of AI expansion. (In fact the routine was bugged, until I repaired it, so it was sending wrong units - and believe me, AI performance was suddenly miles better after the fix!). So the change in routine needs to have more conditions, to let the AI figure the best turn-around point in the game (when it is best to start defending my fortress instead of ruthless expansion).

It is really not simple to determine such a point, especially with MoM having so many exploit prone tactics (Invulnerable GS, invisible warsphips, buffed up slingers). The non-vicinity of enemy stack is deceiving as well. Windwalking can throw a stack of doom on AI's capital in 5 turns from distance 25.

[momfan]

So the change in routine needs to have more conditions, to let the AI figure the best turn-around point in the game (when it is best to start defending my fortress instead of ruthless expansion).

It is really not simple to determine such a point, especially with MoM having so many exploit prone tactics (Invulnerable GS, invisible warsphips, buffed up slingers). The non-vicinity of enemy stack is deceiving as well. Windwalking can throw a stack of doom on AI's capital in 5 turns from distance 25.

Perhaps some arbitrary point e.g. turn > X, gold > Y, total power > Z or some combination thereof could signal the AI that it no longer needs to depend on the fortress to send forth units.

As for the "enemy nearby" issue, given how fast buffed stacks can move I think a primitive "visible by fortress" check will suffice. It is not realistic to account for every exploit. Windwalking is not the only problem. Flying warships with Wind Mastery move 8 squares per turn. Heroes with movement-boosting items plus pathfinding/waterwalking (or wraithform) can move 10 or more squares per turn. No realistic way to defend against these attacks, so I suggest you don't bother.

[kyrub]

The problem is that AI very often "parks" a unit near enemy city for unlimited time. It's mostly triremes, but I have seen other units as well (on an island, for instance). Sadly, it happens more or less in every game. This would totally paralyze the capital. I could check for triremes, but then I would have to check for empty triremes, which on the other side becomes really difficult and space consuming. The other part of your algorithm seems good. I'll think about triremes more.

Btw, I'm implementing your mercenary suggestion as well, seems pretty solid and down to earth. Thanks for assistance. This will do wonders for "Hard" level difficulty.

[momfan]

The problem is that AI very often "parks" a unit near enemy city for unlimited time. It's mostly triremes, but I have seen other units as well (on an island, for instance). Sadly, it happens more or less in every game. This would totally paralyze the capital.

I thought we were talking about the AI fortress garrison? Why would triremes paralyze the capital? If the AI sends out the weakest units in its fortress from mid-game onwards, instead of the strongest, what does that have to do with triremes?

And why does the AI build so many triremes anyway? I have never seen AI warships, even when the AI cities have already built maritime guilds. I think under vanilla I might have seen some galleys, but I don't recall galleys or warships with 1.40j/k.

Btw, I'm implementing your mercenary suggestion as well, seems pretty solid and down to earth. Thanks for assistance. This will do wonders for "Hard" level difficulty.

You mean this 6-step process below?

1. When there are enemies near the AI fortress, always buy if gold allows.
2. If engineers, always buy if gold allows.
3. Never buy spearmen or swordsmen
4. Never buy a unit the AI fortress can build
5. Before turn 100, buy if cost <= 30% of gold reserve
6. During/After turn 100, buy if cost >= 100 and cost <= 30% of gold

If so, how are you defining "enemies near AI fortress"?

[kyrub]

I thought we were talking about the AI fortress garrison? Why would triremes paralyze the capital?

Because the AI will interpret the trireme as a danger, enemy unit nearby. And what do you do when there is a node close to the city and the enemy captures it and there is a garrison? Is the city in danger? - I don't say it is impossible to discern, just that it is far from simple. And the AI improvement is not massive.

And why does the AI build so many triremes anyway? I have never seen AI warships, even when the AI cities have already built maritime guilds. I think under vanilla I might have seen some galleys, but I don't recall galleys or warships with 1.40j/k.

AI builds less triremes than in vanilla. I specifically targetted the nonsense numbers. I am surprised you don't see any galleys or warships. I am sure they were seen in my spectator games (galleys 100%) - e.g. some 140i version. I think I downgraded the boat building a bit since, but no galleys at all? That's strange. Maybe AI fills its (now: lower) boat capacity with triremes -> no galleys?

- Could you try to destroy some AI navy and see what it builds?

You mean this 6-step process below?

Yes. I put in another version, in fact. < 70 turns, anything bar spearmen, swordsmen, <125 turns any unit with cost >= 80, > 125 turn only top units with cost >=120. By the way, I am pretty sure that poor mercennaries decision were the source of typical complaint: why AI builds spearmen in turn 200? It did not build them (very low chance), it bought them from merchants. As a result, the fortress defensive forces will improve in quality!

Strange thing: The dwarven engineers are NEVER offered to any player. They are specifically excluded.

[Asfex]

At least, I have a game 1.40k with the galleys under AI control.
2. May be, the point "Ai will newer buy spearmens" is the same "Ai start select better quality army to defend fortress."

About world creation: I wonder, how often the nomad city stands on the platoo, with no ocean. So its ability to build shipyard , then merchant guild .. become useless. Is it hard to place neytral cities with the ability to build shipyard near the ocean? At the stage of world creation?

[FrancoK]

Strange thing: The dwarven engineers are NEVER offered to any player. They are specifically excluded.

Very strange. I recall hiring dwarven engineers in vanilla, but it was only once, more than 10 years ago, so I can be wrong.
If you say the code exclude them, I'm definitively wrong.

I never see a settler offered as a unit. Are them excluded as well?