What an incredible game. I'll be spending a lot of time in this thread I think - I'm looking forward to the Western release so we can get more folks in here. There's a lot to unpack with this game.
So the rough timeline of the game is:
-Project Gestalt fails and humanity is eventually wiped out (the events of Nier)
-Aliens invade earth and Emil helps the surviving androids defeat them. However, the victory is hard fought, and the machines the aliens used as soldiers are never completely wiped out.
-Project Yorha is started to give androids - whose sole purpose originally was to protect humanity - something to believe in. Data on humanity is stored on the moon and the flashy Yorha units are designed with a combination of android and machine parts.
-The first test of the Yorha units, meant to collect data for a second model, leaves one survivor - A2. A2 has a heightened tactical awareness and realizes she was sent to die, and goes rogue. Her analytical skills are the basis for the special operations E units.
-A scanner unit is designed to aid with data collection, but problems soon arise as it's discovered that he will always eventually discover the truth behind Yorha. An E-class assassin unit, disguised as a battle unit, is assigned to him to surreptitiously keep him in check. He is killed and reformatted/manipulated or guided into situations where he will lose the information regarding the purpose of Yorha (through brave sacrifice, "accidental" death, etc) without ever realizing he's being watched.
-On their data collection missions, 2B has had to kill 9S many times. She puts up an emotional wall between them, which explains her seemingly irrational behavior throughout the A/B routes. She has developed a love for 9S.
-2B and 9S investigate machine activity and discover Adam/Eve, who are a machine/android hybrid developed by the machines, similar to the Yorha units. They are "superior" to the Yorha, as they are connected to the vast machine network hivemind.
-Some machines have begun to leave the network and develop self-actualized consciousness. 2B and 9S get help from Pascal and his village of similarly "free" robots.
At the end of the A/B route, 2B allows this loop of 9S to continue. Sadly, this is the beginning of the end.
-9S discovers the truth about Yorha and humanity. Coupled with the distress caused by 2B's death, his mental state begins to deteriorate.
-A2 continues her machine destruction mission without Yorha, but after absorbing 2B's memories through her sword, begins to notice the same things 2B noticed during the game re: the machines exploring consciousness.
-9S begins a similar crusade to destroy all of the machines and also A2, fueled purely by rage.
-Their paths converge at The Tower, a data collection facility similar to The Bunker, created by the machines (or created specifically by Adam? I'm a little unclear on the relationship between Copied City and The Tower)
-From here I'm also a bit unclear on the details - is the entire cycle
implied to repeat, or is this the first time these circumstances have forced the endgame choices/9S's eventual discovery the thing that always repeats?
on the Machine side:
-Without their alien masters, the machines continue with their programmed mission of destroying all of the androids.
-Some machines eventually disconnect from the network that controls them and gives them their original purpose. Many different groups split off, developing in different ways.
-A primitive tribal society in the desert.
-A colony obsessed with the human reproductive system, eventually responsible for the creation of Adam and Eve
-A village of philosophers/thinkers who explore the human concepts of economics, gender, and class under Pascal's guidance.
-A hedonistic group who take refuge in an abandoned amusement park and busy themselves with entertainment.
-A group in the forest who crown a king and organize themselves in a feudal state with a dynastic ruling class (with no actual way to continue the dynasty)
-A group who build a creation myth around the factory in which they were built and develop a Judeo-Christian style religion.
-It's noted in a codex entry that lots of these groups exist and always collapse "almost as if they were meant to" as nearly all of them draw from human practices that were eventually wiped out or simply fell out of practice, replaced by new practices. The religion is the most obvious example of this, but separated from the network, each group had to search to find their own meaning in the world, and turned to human archives for answers. As the Yorha commander states in a cutscene, "everyone needs a God to fight for." While the androids created a mythic humanity to rally around as their "God," the machine groups searched for new reasons to live.
-Adam and Eve, fascinated by human data, lure 2B and 9S to the alien mothership and attempt to get them to take them to the humans so they can evolve even further, ironically unaware that just like the aliens they rebelled against, humanity is long gone.
-Adam kidnaps 9S for leverage and is defeated by 2B.
-Eve, moved by the loss of his brother, goes haywire, and in turn drives the machines still on the network berserk.
-Eve is defeated, but the networked machines do not stop. With no one "at the helm" of the network, so to speak, machines begin to go haywire.
-The machines not on the network also start to malfunction, as previously hinted at by logs. The religion becomes a death cult. The tribe becomes a Mad Max-ass war party. The hedonists become mindless zombies. The pacifists have no means to defend themselves.
-The Tower recognizes that it's time to recycle all of these parts and begin anew, and begins sending the resource collection units out to keep all of the parts and data so they can begin again.
-Something I'm unclear on here is if The Tower is the collective consciousness of the network, or if it's a separate entity.
Obviously there are waaaaay more details to pick apart with this game, but I *think* that's an okay-ish rundown of the events of the game. There's a bunch missing simply because there's tons I'm sure I missed/I haven't read through all the logs yet. There's a lot more I wanna write about for this game.