AI overland stack/unit movement strategy

[Seravy]

I'm thinking that maybe a mechanism to force the AI to patrol and not use garrison stacks closer than X tiles to an enemy (not neutral or allied) stack that has at least a certain size (or total cost) is a good idea?
Doing this would prevent the AI to send out units one at a time near enemies, and would make sure cities aren't left undefended when a major attack is coming.

The only possible downside I see is, if the human player puts a stack next to all enemy cities, they AI will not be able to build stacks normally, and will be stuck at only using units from the "overflow", the weak stuff that gets pushed outside as 10th unit in garrison. So they can in theory keep all the strong units "locked" in the cities while killing the weak ones that leave. (which might still be better than them killing the strong units that leave one at a time?)

[Nelphine]

Make it a random thing based on personality. Mame all personalities have a greater or lesser chance to choose to build with enemy stacks nearby, that the human can't simply block cities that way.

For instance peaceful might check its chance every 20 turns, and have a 75% chance not to build stacks with enemy stacks nearby. Maniacal checks every 12 turns and has a 40% chance not to build stacks with enemy stacks nearby.

[Seravy]

Every X turns implies the result and the timer is stored. That's not an option.
Unless it's not random but predetermined based on turn count (such as, always from turn 20 -40 and never from 40-60) in which case there is no need to store data.

[Nelphine]

Ah, nope, I meant to have the result stored. I mean you could just do it every turn but that would wreck stack creation. The timer would always be the same, so it wouldn't be stored, it would just be updated once every so often, similar to peace status.

[Nelphine]

Might have to rethink shadow demons. I don't suppose there's enough space to build interplanar stacks? Life being the only AI that can cross planes without portals means its very easy myrran AI to get stuck and not be able to threaten the human player. Human just needs to have 9 strong units on the towers, and even if the AI would win the battle, they won't attack in the first place (things like Lionheart magic weapin elite jackal riders are enough that unless the AI happens to form a stack of 9 great drakes, they'll literally never attack the tower), preventing them from getting to arcanus, so the human can literally just not garrison anything on arcanus, build stacks behind the towers, and only attack when its safe.

Chaos and nature can blizzard/fire storm, life can cross the plane, sorcery have dispelling wave and will win with SoM, leaves death needing something.

[Seravy]

If the human player can clear and garrison all 6 towers with such powerful stacks before other AI clears it, they deserve to win?
...besides, the AI has more resources so 1 plane for both is good for them, not to mention they will eventually get that stack of 9 demon lords or death knights or wraiths or whatever else.
And what good would 1-2 shadow demons on the other plane do if the human player has such forces, anyway?
(ok, they can find and curse a few cities if lucky but that's about it.)

Specifically mono death has
-Demon Lord and Death Knight (and most likely Wraiths), strong enough to attack that stack in groups of 9.
-Demon Lord produces a lot of power per unit - the wizard gets increasingly powerful while you are merely preventing them to get to your plane.
-Final Wave - you are able to seal the towers, but you can't mass-produce troops to take advantage of the situation and get ahead for starting an invasion.
-Evil Omens and Eternal Night - even greater power/casting advantage
-Warp Node - they don't need to scout Arcanus to disable all your nodes. This paired with Eternal Night is a major blow to any wizard's power base.
-If they ever had any units on arcanus, they can curse cities they have seen before.

[Nelphine]

No, demon lords are only barely strong enough to attack that (remember I'm not talking about winning, I'm talking about strategic rating so that the AI thinks they can attack at all). Death knights are a tiny bit better but not much.

I actually forgot about final wave. That's an excellent point. Might be enough. Though I'm not sure relying on one specific very rare spell is a good idea.


And note, I still agree that 1 or 2 shadow demons at a time is mostly useless (although just being able to curse things is actually an extremely helpful thing. Basically that would put death into SoM position - they could curse and warp node everything and win by simply being ahead of the human regardless of fighting.)


And my point is that in the hypothetical situation where the myrran AI is the 'last boss', then its absolutely worth it for the human to literally empty ALL their garrisons (city and node) to garrison just 6 towers. Usually in this situation the human has far more than 6 garrisons to draw on - probably enough to have 2-4 stacks for each tower. These stacks don't have to be the invincible ones I talk about in my first post as long as they can hold the towers long enough to build those invincible stacks.

Then once the invincible ones are in position, whatever is left can be sent to attack indiscriminately because the AI literally won't attack the towers.

[Nelphine]

On doom stacks. Having played several more impossible games, I'm seeing the use of doom stacks a fair amount. I can imagine a player who doesn't use high vision radius units a lot having immense problems. Even oracles and nature's eye don't give you enough warning before the doom stack attacks, so either you have to have extremely strong defensive garrisons, or you have to see it coming and intercept with your own doomstacks.

However, its hard for me to judge what its doing to the defensive abilities of AI.

My playstyle specifically lets AI build up a fair a bit so they'll have more developed cities for me yo steal, but then when I attack, I'm attacking with one or more stacks that can fortress spike. Defensive garrisons mean virtually nothing to me, so I rarely pay attention to how strong they are.

Overall I think doomstacks are working well. Current game, 1405/1406 and the AI has 6 cockatrices, 2 basilisks, and the warrior mage roaming around. Nasty stuff.

The ai also love to stack with the windwalker, which if I'm not paying attention is SCARY. 'Oh look, speed 2 waterwalking units.. Holy hell why did they move 5 squares over mountains??' 'Banished'

[Seravy]

I think there might be one part of the doomstack algorithm that's "unsafe".
What if the unit picked has wind walking and moves alone to get included into the doomstack? That can result in dropping the other units and let them drown.

I've thought about it and I believe this is probably not prevented anywhere. Existing AI movement should be safe anyway - these are the existing movement types :

Move Settler. Settlers will never wind walk.
Move Engineer. Same as above.
Move Spirit. Same as above. All three are too low priority to get targeted by a Wind Walking spell in any reasonable game scenario.
Build stack (continental). Safe, the source tile is always land.
Land to land, or land to sea attack. Same as above.
Board ship, disembark, other ship related movements - a windwalking stack will never do it and even if they do the ship carries the units no matter what.
Pull units for garrison - only works from the same continent.
Sea attack or move to target continent - always moves entire stack.
Plane Shifting - Wind Walking units are unable to do it for this reason.

Doomstack creation falls into neither. It can happen over water and it can split a stack. We can't say "wind walking units never do this" because two important very rare creatures are naturally wind walking (archangels and djinn) and they should participate in doomstacks.

So we should most likely add a check and mark windwalking (native or enchanted) units that are on a water tile but have nonflying/nonwater units along as invalid. Not trivial but I think there was space left for it? I hope so...
(can't include other flying/water units because that includes other members of the doomstack itself, so it'd drop the windwalker immediately after it joins)

(Djinn and Archangels and the Wind Walking buff is also likely to hit strong creatures/heroes)

...btw windwalking units that don't also already fly/waterwalk/etc are already excluded. But Djinn and Archangels do.

[Nelphine]

Probably not possible, but what if you look at the whole windwalking stack? So if the archangel is with buffed hordes, they would all be eligible for the doomstack, since they are windwalking.