Originally posted by Blake
I'm 100% responsible for the AI in BTS.
Making the normal AI wussier was MY decision, granted it was a decision made partially on the basis of impassioned pleas (pfft, whines) for less unit spam, I am by nature every bit as cruel as Sirian when it comes to making life difficult for players, and yet that cruel tendancy ends up getting moderated, probably by compassion.
Basically there was:
Things I had time to do
Things I didn't have time to do
I can't think of anything I implemented which was not included.
Have you seen the list of changes in BTS? The number of new systems? To say as little as possible, there was not nearly enough time to perfect things, most time was spent making sure as little as possible was broken.
If I had spent the time to make an impassioned argument for replacing Aggressive AI with Peaceful AI then I'm fairly certain it would have happened - in spite of the obvious backlash about "Pointlessly changing things around" (trust me, however pointful something is, there will always be some who find it pointless...).
But other things got my attention (requiring impassioned arguments ), when there are things which are broken, those things take precedent over things which aren't perfect. Perfection is unattainable anyway, while not broken is attainable.
This is not a criticism of the BTS development, it can be called corporate reality if you want. Was BTS too ambitious? Maybe... probably... but I think it's still better than not being ambitious enough.
To further explain AI military behavior.
A naturally militaristic AI like Alexander or Monty will still make a respectable military effort under normal settings, in AI vs AI wars, it's all relative anyway. Some AI's have to be bad at defense, so others can invade them. In BTS the AI are far less "samey" in their strategy - in short they can pursue goals, but obviously in min-maxing their metagame they sometimes make themselves extra vulnerable to be invaded, it's the price of not being samey/predictable.
Aggressive AI no longer causes the AI to have a relationship penalty with humans. Basically it can be said that the AI expects things to get aggressive. The pacifist AI's aren't actually that much more likely to declare war, they just keep larger armies on hand as to not be easy victims. The naturally militaristic AI's go crazy. In any case if you neglect your army, any AI will notice and with it's larger power will be more likely to declare war and come for you. It is more likely you'll get declared upon, especially if you don't change your playstyle...
The default AI is a bit of a sandbox, you can employ the strategy you want and the AI may interfere with your plans... but on Aggressive AI, the AI can DICTATE your strategy! If Alexander is going to invade you, then you damn well prepare an army or you're going to taken out of the game! Even with the best prepeardedness if you fail to avoid a dogpile you're probably a goner.
On the normal setting, you just play, it's casual.
On aggressive AI, you adapt, it's hardcore.
Note that the vast majority of people who buy the game are not hardcore. Even those that are (proclaim to be) often prefer more of a sandbox style, one of the most common complaints was along the lines of "I don't want the AI forcing me to adopt a play style", in other words the player has to be choose a strategy, and the AI must accommodate them to a degree by not being too aggressive. While Aggressive AI, will be as aggressive as it darn well pleases.
Note that Aggressive AI, due to spending more on units, techs significantly slower than the default AI, if you can somehow stay out of the crosshairs it's actually easier to win peacefully - the default AI can be a speed demon when it comes to research.
What do I mean by difficulty?
Take this as an example: I played a game on emperor level and got a good start, I wiped out my neighbor, then another neighbor. But during that time an AI "tech whore partnership" of Elizabeth and Roosevelt had teched to the end of the tech tree while I was really nowhere near it, the warmongering, despite being successful, had slowed me down. That's part of the new balance of BTS - the AI's can under good circumstances tech very rapidly - in Warlords the AI - even at emperor - was easily capable of not getting to the end of the tech tree before 2050, meaning the player could take all damn game long consolidating a large conquest into an economic powerhouse, in BTS players don't have as much slack, so even if conquering your neighbors isn't harder it can be harder to actually win the game. That's something you get with default AI - you dick around invading people while some AI's refuse to fight and tech off into space. It doesn't happen predictably and I'll put it like this:
If you play at a difficulty which is exactly at your skill level, with 10 players:
10% of the games you should have an easy time, because you got a "top 10%" start point.
10% of the games you should have a very uphill struggle, because you got a "bottom 10%" start point.
Some easy games are to be expected.
(Note: Most players play far below their "equal skill level", in that they expect to win 100% of games, rather than 1/N games where N is the number of players used, this paradoxically is true of multiplayer too - the players just feel like they suck when they only win 1/N games)