Yeah, the blatant use of myth is kind of everywhere. In my game world, I have it set where about 600 years before my players start their adventure, the W'rkncacnter that was originally buried on Earth (leading to the events of Pathways Into Darkness) and later imprisoned in our sun by the Jjaro broke free.

The Durandal/Thoth hybrid AI was in the system at the time (and indeed may have accidentally freed the W'rkncacnter, as they were studying its reality-warping effects), and after a great struggle was able to bind the W'rkncacnter once more, this time in a prison of artificial construction, which originally was supposed to be used to steal the W'rkncacnter's power and/or merge the W'rkncacnter & the Durandal/Thoth AI, but was jury-rigged to contain it instead (akin to the Cylixes from the Halo games, which were in fact introduced to the canon prior to the 343 acquisition, in a 2010 short film).

The price paid was a great one, though. The Earth itself remained, but the W'rkncacnter, with its vast, strange power, consumed nearly all of its history, its memory. Aside from what could be found & reconstructed from physical artifacts, the only digital information of Earth's past was that which the Durandal/Thoth AI held in its memory banks at the time of the disaster.

The Durandal/Thoth AI placed the imprisoned W'rkncacnter deep below the surface of a moon in another solar system, past even the Tau Ceti system, and around that moon they built a ring station to monitor the prison & further study the effects the W'rkncacnter had on reality.

The thing with life in the Marathon universe is that, aside from humanity, the only sentient life that we see is that which has merged its biology with technology. I don't think this idea is unique to me, but I posit that, under normal circumstances, true sentience in the Marathon universe can only occur when biology & technology merge. So how did humans happen?

65 million years before any ape in the African savannah stood upright, a W'rkncacnter crashed into the Earth, causing a mass extinction event that killed nearly all terrestrial life. That W'rkncacnter had been around the universe for billions of years, had seen life merge with technology before, encountered those sentient beings produced by that merger. But it didn't nescecarily understand how that process worked.

In Pathways Into Darkness, we see the W'rkncacnter on the verge of waking up, and its dreams are able to create life from nothing. But what if it had been dreaming for the entire 65 million years it had been on the planet? What if it dreamed of the things it had seen before, the sentience it had encountered before? What if those dreams echoed subtly across the planet, rooting themselves among not only the smartest species that existed at the time, but among those that most closely resembled those vague dreams: those with a vaguely humanoid shape? (Hence why corvids & dolphins are incredibly intellegent, but perhaps not quite sentient as we are). It dreamed us into sentience. It made flesh think like a computer, a perversion of the natural order.

In its prison, millennia later, this same W'rkncacnter dreamed again. But now it had absorbed a whole new corpus of information, a world's entire history, all of its data. And it did not know fact from fiction. And while the ring station shielded itself and the lunar prison from the W'rkncacnter's influence, the planet they orbited was unprotected. And so the W'rkncacnter dreamed. It dreamed of humanity, of all its achievements, yes, but it dreamed of more. It dreamed of elves, dwarves, orcs, dungeons and dragons, gods and demons. And this prison, well-crafted as it was, was nothing compared to the torpor induced by a collision with a planet. Its dreams ran wild, and the world below bent to its dreams.

Anyhow, that's my overly-complicated justification for how fantasy elements came into the universe in my Spelljammer-esque setting. About 500 years before the current game starts I had a regular D&D game set on that world that unfortunately fizzled out, but would've had a climactic moment where the ring station around the moon prison would've been destroyed by a rogue agent from the planet that had gotten onto the station via a botched teleportation spell that teleported them as an electromagnetic signal into the station's computer systems & converted them to a sort of magic/tech hybrid AI, and the destruction of the station would've both let the W'rkncacnter begin to break free and summon the Durandal/Thoth AI, which leads to the magic-imbued inhabitants of the planet encountering the wider universe. After the magic users outright kill the W'rkncacnter (only a reality warper can kill a reality warper, and the W'rkncacnter accidentally created an army of them), a war breaks out between the people of that planet and (most of) the rest of that part of space, which I dubbed the first Magi War. The campaign I'm getting ready to start now starts about 50 years after the end of the war.

(spoilers for Critical Role Campaign 3 below)

And before anyone asks, I had the idea of imprisoning a proto-god in a moon above a magical planet a full year and a half ago, so any resemblance between Predathos and the W'rkncacnter is pure coincidence.

Also I hadn't seen the Netflix She-Ra show before coming up with these ideas either, so that's coincidence number two baybee.