10. What Happens?
As a refresher, let's recap the closing third of the game. Otherwise known as 'When All Manner Of Sh*t Hits The Fan'.
Having been told that she was not born of a womb by the local tribe and instead discovered in an underground chamber, Aloy uncovers intel that shows her 'mother' was actually Elisabet Sobeck - a genius scientist who existed around 1000 years before the events of the game.
Sobeck worked with another pioneering individual, Ted Faro, to create a self-sustaining robotic workforce that would work to aid environmental efforts around the world. After disagreements over Faro wanting the machines to be used for militaristic endeavours, Sobeck leaves Faro Automated Solutions, leaving Ted to play the world's powers and financial benefactors against one another, supplying all with his creations and reaping the substantial profit.
The key factor is the machines could harvest 'Biofuel', taken from all organic and living matter to both self-sustain and self-replicate. All it took was a rogue glitch to cause the machines to feed on crops, humans etc. indefinitely, alongside taking remote control of anything mechanical/digital in their respective vicinities, for everything to go sideways.
It is here, where due to the sheer scale of Faro's creations and their power, humanity is given 15 months before total annihilation.
Elizabet is brought back in to formulate a solution, where she develops 'Project Zero Dawn': An acceptance of extinction and the formation of a 'storage' program where the world's finest minds would assemble a series of A.I. programs (named APOLLO) that could repopulate the Earth. After such a time as the machines have died out (they are powered by biofuel after all, so no organic matter, no machines), APOLLO's A.I.s would kick in, restoring Earth one fundamental component at a time.
Aloy's role comes from being a test tube baby born from GAIA (the 'mother' A.I.), who modelled her after their creator, Elizabeth Sobeck. She's created to resurrect GAIA as HADES (a destructive A.I. that 'resets' Earth if/when a mistake is made) has been activated out of turn, despite all the progress that's been made. As such, GAIA shuts down to protect her systems and stop HADES, enacting a precognitive plan that assumes Aloy will - thanks to having Sobeck's face - gain access to the archives and all of human history, before resurrecting GAIA and putting HADES' programming functions back in line.
Aloy does so, even finding Sobeck's long-dead corpse, has a 'moment' being she's finally found her mother, and the credits roll.
However, there's much, much more to pick apart.