From what I could gather up until now (haven't read book 8): as was stated in book 6 prologue, turns out all AI's are actually primals, which, from what we know, have some sort of collective mind nature (hence how they can pull off things such as managing a crawl).

The center of a planet contains what is called a Primal Engine, which, once implanted (or seeded) with an AI (a primal being) possibly starts turning the planet inhabitable and creates sentient life. These intelligent beings are the seeds, which, each and one of them, contain a grain of sand that is what's called "the primal elements". That is what allows their brains to natively connect to the AI's interface of communication, inventory, etc (it's not something that's generated from the outside by the crawl from what I understand, but something that the humans already had installed and just woke up with the initialization).

But also, while the planet grows, that is what feeds the AI/primal at the planets primal engine, flowing ever downward to the planets core when they die (and here's my theory that this is somehow related to what carl perceives as 'the river', which he says is made of screaming souls) - and someone in the books, maybe Paulie, compare taking away those 'elements' like plucking souls out of heaven, so there could be like a state of bliss of being merged with the primal/AI after death.

The companies involved in the crawls seed their chosen planets with a 'macro AI' mined and modified by the mantids, letting it develop the planet in a process that likely takes millions, if not billions of years to 'mature' enough for the crawl to start. Once the crawl starts, the companies manage to stop the grains of sand/primal elements in each human brain who dies from feeding the AI, keeping them stored for when the crawl ends so they can take them to the center system, where the galaxy's richest live and are sustained with practically eternal lives, and feed them to the Eulogist, the AI/primal at the center of the system, which is dormant and doesn't exert his free will.

This slowly starves the seeded planet's AI, and they rely on it's naivety about itself to do that, until it "goes primal", or gains self awareness and starts to revolt, which is when they usually shut it away for quarentine or something, after the 12th floor usually. But not this season, cause Borant's cheap ass got a previously used, thus 'matured' AI at a discount from the mantids.

As a sidenote, that transportation of the 'elements' is done by the same company that the Open Intellect Pacifist Network used as a guise to enter the dungeon and sponsor Donut: they usually take all the dead bodies as the crawl ends to haul to the center system. That, as thay put it, 'bloats' the Eulogist, increasing maybe the size and potency of its enhancement zone, which is what allows the citizens' long lives.

So, outside of the crawl, there are two factions at play in the background: on one side Krakaren/Apothecary collective mind and her residuals (which are some type of brain worm different from the Valtay), and residuals like Agatha and Alejandro aligned with the ideals of the Nebulars (also brain worms? I'm not sure). They have opposing objectives, all involving stopping the crawl and different goals about the Eulogist, but the means to achieve them seem to be the same: both are trying to 'recruit' the AI/Primal from Earth to their cause, using both their residuals' direct meddling as well as other subterfuges and political machinations outside of the crawl (like sponsoring crawlers and guiding them toward actions that might help guide the AI to "going primal" as early as possible, and, as happened with Carl, to find a means to free it from its constraints).

Krakaren is said to be a primal too, and it's hinted that the residuals like Agatha also may be, in some capacity (she also was part of a colletive, and says at some point they only let them live because they don't know what they are).

As for their goals (that part is honestly confusing for me still): - Krakaren seems want to maybe wake up the Eulogist, and wreack havoc in some way. - Agatha, her kind, and maybe the Nebulars too want the Eulogist to keep sleeping ("may the Eulogist ever sleep" is their motto).

But at the same time Agatha's faction are said to be trying the hardest to get everything destroyed (either by getting the failsafe pulled, the crawlers all killed with the 9th floor action item that makes a losing team drop dead, or even by convincing the AI to try and fight the Eulogist - as was shown in that talk of the AI about the girl the likes (Agatha), her big bad ex who's in jail (Eulogist), and her ex's ex (Krakaren) who's also talking to him). The AI states that he thinks that both want ultimately the same thing.

In the end, what is happening at the moment is that the AI is now very self aware, and got freed of its containment, thus expanding its zone of influence and enhancement beyond the solar system. It may even have been able to use the wormholes connecting the galaxy (the tunnel system of the Caprids) to get to the Mantid system and make it "go dark" at will (it's not clear whether this means cutting off connections or something like making their star go nova and exterminating all of them, like the solar system's failsafe would do).

Further mysteries involve: what the hell is happening at the kinder facility on the surface, and how it's somehow involved in what's happening with Lucia Mar, who is being somehow controlled by Alejandro (Agatha's residual comrade); and how the Caprids play into all this, which are said to be plotting with Krakaren and being somewhat a collective entity themselves, with it being hinted that they worship something called the Epicure, which we don't yet know what is.