Survival is a theme that is touched upon quite a lot, and not only when it comes to the anime medium. Most of these kinds of series tend to engage this rather generic theme with interesting and good-looking fights, completely ignoring the plot's development and the characters' growth on the audience, instead adding a lot of gore which apparently triggers the "feels" of ignorant masses because, you know, losing someone precious is hard. There are many ways to strike a certain series despite the generic concept, instead of doing that you might as well develop some characters hence making it feel not as retarded. Kabaneri does not do that, and it also is full of the "retarded adults syndrome", it being apparent in the whole anime, despite the main characters themselves being idiotic. Consequently, all it manages to be is a copy of Attack on Titan, if not even worse than that, and yup, that ain't good at all.
Koutetsujou no Kabaneri takes place in a post-apocalyptic Earth, in the face of an industrial revolution, where unknown creatures named Kabane have appeared, them eating flesh and drinking human blood, hence becoming humanity's natural enemy. Once a Kabane bites a human, that human becomes a Kabane and so on. Post apocalyptic Japan has been colonized into train stations, which themselves are cities and are surrounded by walls, with trains travelling between them for many reasons, including provisions and soldier transfers. Interesting huh? Well, despite some of the points of the concept being indeed interesting, such as combining a steampunk setting with survival in a world that has been destroyed were, not really, because there was nothing left in order for the concept to be supported, therefore the execution being extremely weak. Letting alone that the dialogue was really cringy and reminded me of SAO, everything else except the production values was, likewise. After all, trains can not save anything.
The havoc has wreaked, and then there is our main character, Ikoma, who is an overenthusiastic fellow. Guess what, he wants to kill the Kabane in order to avenge his sister who was bitten by them. He develops a weapon which can kill Kabane in an easier manner, and boards Koutetsujou because the city is not to be inhabited anymore with several other people, to whom I will get into later, him broadening his horizons and deciding that it's not fair that only strong people have to survive or whatnot. The moods of the main character change quickly depending on the situation, so he sometimes is extremely badass whilst in others you wanna hit him in his head with a screwdriver because of how retarded his actions are. Another bad thing about him is that he actually is the most likable character in Kabaneri. Unfortunately.
Enter Mumei, our second main character, who is your generic fare of courageous on the outside, feelsy yet manipulated in her childhood on the inside. Not that it matters, but it is the revelations about her that are extremely lazy, leaving me with a hand scratching my head. She is the one to inherit the standard "strong people survive, weak people die". The portrayal of that ideal is really bad, as it is played with and goes round and round to reveal that, in the end, Mumei should not become like her mum who was killed by the Kabane, and that she should remain strong and get experimented in order for her to become her "brother's" puppet, becoming a Kabaneri and wandering around like an idiot not knowing what to do with her life.
Mumei's symbol of admiration, Biba, whom she calls her brother, is the most interesting character in the whole series, appearing relatively later in the series, only for the audience to learn that he is the leader of the Kabane extermination troops in order to satisfy his egoistical means, adding yet another idiotic character to the cast. By the end of the series, he has become your common villain with only a flashback to be supported with, following the quote "in the face of our supposedly enemies, he is the one that should be exterminated because of his evil means". Apart from these three, there are other side characters which are cookie cutter like our mains, including your Ayame-sama, her knight who is always by her side, Ikoma's friend who dies for the sake of melodrama and many many more, including the retarded adults whose IQ is minus 150. Bad writing is all over the place, there are no explanations given about what the hell the Kabane are, and true, some but few characters might have gotten some development, but that was done with some of the lamest, laziest and most boring excuses aka. Plot devices I've ever encountered in my life. Along with an ending that obviously was not the best, after the trainwrecks all the other episodes were, the outcome most surely is not that noteworthy.
What Koutetsujou no Kabaneri lacks in every other department, somehow wins when it comes to the art and animation sections, because you might as well make something bad at least look good. The backgrounds are great, them being the best point of the whole series, the sceneries being fresh and given a good amount of lighting. The choreography of the so-judged significant battles, especially the ones in episode 8, is pretty detailed and make up for some shortcomings incoming with the drop of budget in the middle episodes, although it looks a whole lot like Attack on Titan's 3D Maneuver Gear. The character designs are as a matter of fact not bad-looking, but they somehow are unappealing in certain moments, especially when it comes to the character's faces. Mumei's face is a huge representative example, as when included in light-hearted moments, like those where she plays with the kids, where her face looks extremely moe-ish and unfitting to the whole thing (her armpits and legs make up for it though). A character design that I personally liked is that of Horobi, which is quite detailed and looks great in a certain battle scene. A plus, amongst others, would also be the costumes of each and every significant character, which are cool enough and remind me a lot of a crossover between the cheap clothes used by people back in the industrial revolution along with some style to support the steampunk setting. Overall, despite the animation quality drop in some episodes, the section as a whole smelled success, over how bad other things in the series were per say.
Soundtrack-wise, Koutetsujou no Kabaneri is fine. It comes down to each person to how much they will like edgy music or not after all, and in Kabaneri's case, the opening and ending songs have fitting music and lyrics to the series' concept. The OST was misused some times, a good example being Mumei's flashback where a happy-toned song was used in a scene which was downright sad. The voice acting was quite okay, though forgettable most of the times, the exception being Ikoma's, which was both exaggerated and unforgettable in a whole bad way. He sounded like someone who was getting laid off at the time and place he spoke in. Consequently, the soundtrack was above average despite myself not being a fan of Sawano-esque music because it is repetitive as heck.
To say the truth, I somehow enjoyed Koutetsujou no Kabaneri quite much, with both its goods and its of significant amount bads. I enjoyed the fights and their choreography, the sceneries and the backgrounds and I laughed at how tarded the characters were. Noticing how much of a "Nothing happened: The Animation" it was, was incredibly fun as well. It literally went round and round and achieved nothing but nothingness, void, darkness. And even if it did achieve something, it was by default pointless, because in the end, nothing happened. Only edgy teens trying to survive in a post apocalyptic world full of blood-drinking creatures, generic and undeveloped villains and retarded adults, with the whole meaning of the word. I would have enjoyed it way more, hadn't it tried to be as supposedly serious as it was in the first place.
In conclusion, Koutetsujou no Kabaneri is just another one show of the kind which includes overhyped Attack on Titan-esque shows like Black Bullet. If you expect a show with relatable characters, a realistic depiction of survival and interesting yet explained lore, avoid it like the plague it is. However, if you just need a show to cool off with and do not care about any kind of flaw and shortcoming, engage Kabaneri of the Iron Fortress like the ephemeral and cathartic journey it is. To finish with a bang, I am going to quote a friend: "It will be performed as an opera on the holodecks of the ships that disperse us into the heavens. We were really just clothed monkeys until it allowed us to transcend our animalism. I shall sing its praises to all that shall come forth and be enlightened. If it was not Clannad After Story that could make you cry, try Kabaneri, that is how amazing it is".