I've put ten-plus hours into the game now. Really enjoying it and the atmosphere and soundtrack are just amazing. The pacing is pretty good, so far, and the game doesn't really do any hand-holding, which is much-appreciated. I think I'm getting close to finishing the game now, or should I say, I'm getting close to finishing the first part of the game since it's more like three campaigns in one.
The story and atmosphere are the big things here. It becomes pretty obvious what is going on fairly quickly in, but the game is written well enough that it stays pretty engaging. The plot is that at some point centuries in the past, aliens came to earth. Rather than invade directly, they sent out robots to work for them. In turn, humans fled to the moon and had androids fight for them. So this is one big proxy war between machines. Initially things appear to be pretty straightforward, with your side, androids, going down to the earth and destroying mindless robot drones, but you quickly find that there are robots with full intelligence and consciousness.
Major story spoiler:
spoiler (click to show/hide)
The android/robot war is completely pointless. Aliens and humans are long dead and the war is just continuing on to give the machines a sense of 'purpose'.
You play as Android 2B with 9S as your companion the first time around, then play as 9S the second time with some bits of new story (and different game play), and then you play as another character after this with a lot of new story and areas to explore.
Massive story spoiler:
spoiler (click to show/hide)
I haven't even gotten this far but found out that what's really going on with 2B and 9S is that 2B pretty much knows all this already. Her job is to watch 9S, who during the course of the game finds out about the android/robot war, and then kill him/wipe his memory over and over again.
The action is good, although I kind of wish this was a pure level-based action game instead of an 'open-world' style action-RPG. There's a lot of unnecessary running back and forth for a good while until you finally get to a point where fast travel is possible. They should have had this available from the start-- The save points you use to travel between have to be found and liberated from robots guarding them anyway. You can equip various chips that enhance your abilities, but if you don't want to bother with this, you can also have the game auto-equip them for you and keep things more action-oriented. The game play is mainly fully-3D hack and slash/shooting, but there's also some SHMUP-style sections and 2.5D platforming/action areas as well.
I'm pretty engrossed in the game right now and it's making me want to go back and check out the original Nier and Drakengard 3 when I'm done with it, although next up is going to be Zelda. Speaking of those other two games, there are a few Nier characters who pop up and there's also a certain type of flower you can spot here and there that appears to be the same as the one Zero wears in Drakengard 3, in what I assume is a nod to that game.