This is the first "first" episode of any of the seasons that I've been impressed by. I was pretty much meh about Season 1, 2, and while S3 Part 1 was an improvement, it still wasn't much of one. Me liking this episode so much might just be because of the context though. Not a whole lot has really happened up until this point, it's been a lot of build up and finally it seems like we are going to get some pay off. I even went so far, after watching Season 1, to skim through the manga and spoil myself on some major events, just to try and hype myself up about continuing to watch the show. I just felt like nothing was happening. So, to see a high stakes battle to reclaim a wall with more than just fighting blobs of flesh. It's something to dig into.
That being said, the music was pretty impressive. I was okay with the OP, but the background music during the actual episode was what was extremely impressive. It really sold me on how intense the situation was. So much so that when all those titans transformed I was so surprised I cried out, "Oh shit!" I didn't expect them to legitimately have a whole army of people who could transform into titans at will like that. I jokingly said to
@SkyOnAnime, "I'm not sure why they are so tense. It's not as though they are going to have to face a 1:1 army of humans to titans." I figured it would just be Beast Titan, Reiner, Bertholdt and some random, brainless titans they collected. That being said, I have a general idea of what happens during this battle, although nothing too specific. Most of what I looked at in the manga was after this.
Other than that, the art was noticeably better than any of the past seasons. So much so that I'm sort of even more salty about OPM2. Granted, I don't think AoT had that sense of "being rushed." They even went ahead and broke Season 3 into separate parts that are airing months apart. I know that AoT3 announced it would be "multiple" parts. I'm not sure how long this battle is, whether it will last all 12 episodes or not, so it's hard to speculate whether "multiple" parts is going to end up being 3+ or if they just meant they were making it 2 cour.
In regards to the actual episode; One of the weirder things that put me off was that Eren used the shell of his titan form to plug the hole. I thought he was going to seal it with the harden skin by like, layering it like bricks or something. I didn't expect him to literally crouch into the hole and leave the shell of his body in there. I'm not even sure if that would technically fill all the space? Other than that, I was glad to see Armin getting some involvement. He was one of the people I managed to like coming out of Season 1. Mostly because I was banking on him having the most potential for growth and character development. Seeing him piece together them being in the walls was nice, and hopefully he'll get a rather active role in this battle.