Good questions all around! I'll answer a few here, as straightforwardly as possible. Apologies if I ask for clarification.
OK. What's the actual origin of the AI cores in Classic?
Why are there always _two_ AIs (not one, not three, not 42) in our section of space?
See:
Basically, once upon a time there were two rival human factions, who made increasingly competent military AIs to do their work. Then the AIs suddenly decided that they liked each other more than the meatbags and conquered the galaxy we're in. It's in the menu screen text crawl.
What's the story with the Marauders? What kind of life do they live?
You know, this is the second time I've been asked about them. I hadn't planned to do much with these guys, clearly that's a mistake.
What's the story behind the Cookie MonsterDevourer Golem?
What are the Dark Spire? How do their Vengeance Generators work, and why were they built?
These will be discussed in AI War 2.
The rest are for other games/expansions.
I thought the AI Cores were some kind of ancient Spire being/device that the Humans created, since I recall one journal noting that the technology behind the AI was well in excess of the technology available to the Humans of the day.
Nice catch. However, the AI is a uniquely human creation.
Firstly, how is Humanity still unprepared for a possible Alien invasion thousands of years after the near extinction of their species?
Secondly, did Humanity or anyone else try and hunt down the last remnants of the AI after the original war? Considering the massive amount of time that has lapsed one would assume plenty of time was given to try and at least see if the AI is still active elsewhere.
A parable: A village is overrun by vipers who poison many villagers, until the survivors band together to kill the vipers. They find the cave where the vipers nest and board up the entrance, saying that they will never forget what the vipers did to their village and they will guard the cave forever. They do until they die.
Their children remember the promise and guard the cave well, but some of them are required to fight in a war against another village. The third generation also remember, but a sudden influx of refugees brings new ways and new stories, and so on down the generations until the story of the snakes and their cave is just one story among many.
And then one day a giant anaconda punches through the roof of the cave and starts eating villagers whole.
Also, what year is it? Both during the original war and in the sequal? There's no real way to figure out the year in game.
Multiple calendar systems are in use and many societies no longer follow a 24 hour clock. Giving a date by our reckoning doesn't really have any meaning. If it helps, think about a time period advanced enough from our own to not understand what "Gregorian" means.
And why are they are so similarly sized and so intertwined? In my current game, AI1's home base has only one adjacent planet but AI2 owns it. How do they get along so well and remain equals, rather than jousting for dominance over each other?
Ooh, nice one. This isn't a spoiler so much as not said outright, but there's only one AI. The two merged into one. So the AI isn't getting along with an equal, it's displaying two facets of its personality.
What are the Spire up to, and did they retrieve a certain someone from their subspace signal?
You're asking about Fallen Spire?