A newbie question about 100 opinion.

[Katheb]

I knew my brother was going to cause trouble, so I did all I could as a diplomacy guy to get his opinion of me to 100. So I assumed all was good at least for a bit until I got allies and what not.

But he attacked me and won (he was military focused) and then denounced me and took my land and game over.

what is the point of 100 opinion if he is going to attack me anyway? or am I not getting the point of opinions?

[CrUsHeR]

Opinion is just one factor. You can easily test this when you read the breakdown of the "invite to court" on a random NPC. Just having +100 opinion is only a factor of +25 in the decision wether to join your court or not. Being family would add +75 acceptance, which would beat the -50 base acceptance (unless they have other reasons to stay where they are).

The factor to conquer you over his claim is obviously much higher than thinking that you're a great guy.

The same also goes for e.g. murderplots, if the personality or motivation are high enough. So your impatient+deceitful+ambitious son with +100 opinion will still murder you.

[Ogami]

Its much more important what their traits are and their claims.
A greedy, ambitious character with claims you hold will ALWAYS scheme against you and try to get those lands, no matter how much they "like" you.

[EA Latium]

There are AI Personalities that determine their behaviour, you can see a small description under characters name.

Edit:
There is an entry as well in the Wiki for the details.[ck3.paradoxwikis.com]

[kaiyl_kariashi]

NPCs with low honor don't put much value in opinion. It is a factor but it's weighted so lowly that pretty much any other factor is gonna sway their actions more than the opinion they have of the target.

[CrUsHeR]

The AI personalities chart above only deals with the hidden stats like Zeal, Honor etc.

Your brother has a just claim on your kingdom, so by any means he should try to take it back. The only connection i see with the AI personalities would be "Rationality", which decides how strong his troops/alliances need to be in relation to yours, before he decides to attack.

[ste]

From what Ive found the AI all behave the same, personalty does not matter, they all behave mindlessly aggressive. If there numbers equals more than yours, its war

Its basically as simple as that.

[EA Latium]

Originally posted by CrUsHeR:

The AI personalities chart above only deals with the hidden stats like Zeal, Honor etc.

Your brother has a just claim on your kingdom, so by any means he should try to take it back. The only connection i see with the AI personalities would be "Rationality", which decides how strong his troops/alliances need to be in relation to yours, before he decides to attack.

That's definitely an important factor in this case, absolutely. I posted it mostly to explain AI behaviour in general, although if the the brother in question was Content let's say, things would have certainly played differently (like the Denouncing part).

[EA Latium]

Originally posted by ste:

From what Ive found the AI all behave the same, personalty does not matter, they all behave mindlessly aggressive. If there numbers equals more than yours, its war

Its basically as simple as that.

That's actually pretty complex under the hood, sometimes they may go for direct confrontation, sometimes they may go the Intrigue route or not even care at all.

[ste]

I dont doubt its complex under the hood, and its intended for all these personalities and everything to play a roll,
but all that complexity can be wiped out just by getting some of the numbers abit wrong.
If my army bigger than yours, equals war over rules everything else then all that other complexity is wasted.

I played the same start many times and its always the same. If a ruler has high enough stewardship to have space in his domain cap, he will start revoking, possibly be over thrown by the tyranny, if he wins the war, he'll give it away if he realise he cant hold it anyway, then repeat.
If hes not at war and an enemy has more men including his allies plus mercs, than whoever, he'll start a war, if he wins that, he'll start another.
if an ememy has less men but spots someone getting attacked by more men, he'll start a war counting them as his troops. Possibly for even the same title and then end up having to fight the winners.

Ive not seen much intrigue, and not alot that made much sense.

[EA Latium]

Try a spectator mode with console commands, you can see many things playing in different ways. That's how it is in the code by the way, you can also check the game files in case.

Edit: This is the Faction bit for instance:

NFaction = {
CREATE_OPINION_THRESHOLD = 75 # An opinion below this value will give the chance of create a faction
CREATE_MIN_SCORE = 15 # Minimum score value to try to create a faction
JOIN_OPINION_THRESHOLD = 75 # An opinion below this value will give the chance of join a faction
JOIN_MIN_SCORE = 15 # Minimum score value to try to join a faction
LEAVE_SCORE_THRESHOLD = 5 # If the join score goes below this value the member will leave the faction
DEMAND_EXTRA_THRESHOLD = 20 # The AI is going to wait ultil have a sum of power and demand greather than the thersholds + this value to press demands

DREAD_MODIFIED_BOLDNESS_FACTOR = 1.0 # The effect of Boldness (modified by the liege's Dread) on the AI when considering creating or joining a Faction (Boldness can never make a negative evaluation score positive - it's a bad idea.)

RATIONALITY_FACTOR = 1.0 # The effect of Rationality on the AI when considering creating or joining a Faction (Rationality can push the evaluation score below or above 0.)

ENERGY_FACTOR = 1.0 # The effect of Energy on the AI when considering creating or joining a Faction (Energy/Lethargy can only increase or reduce an already positive evaluation score.)
}