\\\*\Warning: Potential Spoilers ahead\\\\*
Let me preface this by saying that I'm not what one would call a "strict" reviewer. I have very lax expectations when it comes to anime so my review may not be over analytical and may seem very forgiving. I will also try and be as vague as possible if you've decided to read this review before watching the anime.
I believe anime can be "deep" and move hearts and it can also be intellectually stimulating but most isn't. The Rising of the Shield Hero is an example of such an anime. On the surface there are mature themes; racism, slavery, rape and torture, but these are not presented in such a way that one can compare them to the real world. This is fine. Not all media we consume has to be some sort of commentary on society, in fact, when I delve into anime I generally do so with the intention of not being reminded of what the world is actually like. The Rising of the Shield Hero was unrealistic enough with these themes that it's obvious that they were used as plot devices more than anything else. If you feel betrayed or misled by such things then you're not approaching this media with the right mindset but I digress.
I haven't read the Light Novel so I cannot comment on the source material but it seems to me that this falls into the typical "isekai with dark themes" category. This is in line with something like Sword Art Online where there's a tone of seriousness but there's no actual evident danger to the protagonists of the story. Maybe that's not your cup of tea, maybe it is, but you've been forewarned either way.
The weakest element of this anime is the plot. There are a lot of inconsistencies and oversights that are difficult to look past or swallow because they fall apart when viewed through a lens of what one might call common sense. This is perhaps one of the reasons that are so many negative reviews. Maybe some were expecting a masterpiece and instead were served with the usual anime tropes that don't make sense when we apply our logic to them. If you're the kind of person that's majorly bothered by the MC-tripped-and-accidentally-grabbed-a-boob sort of logic then steer clear of The Rising of the Shield Hero. That's not to say that there are moments like that in the anime, but a lot of the plot is advanced by similar logic masquerading as something more profound.
Character development is probably the second weakest aspect of it. Some might say the MC is bland so the viewer can project onto him but I didn't see it that way. Maybe there are a lot of otakus in Japan that lead a similar lifestyle but I personally believe that the average Western anime fan is a far cry from the typical portrayal of the isekai protagonist. The MC isn't terribly original(but at this point, what MC is?) but he wasn't unlikable. Some things happen that transform him from a mild mannered young adult to a bitter, angry creature and the anime follows his mostly cold "hateful" persona. He does grow, however, and in his anger and hatred he finds that there are still things worth caring for in this new world(this is what I meant by not original). The supporting cast, however, is largely unchanging. The only person that seems to change with the MC is Raphtafilia, his first companion and even then it's a predictable change. These aren't bad things, however, depending on why you watch anime. I find comfort in "waifus" and MCs attempting to redeem themselves not so much because I can place myself in his shoes but because who doesn't love an underdog? (Apparently some of the other reviewers) The MCs main traveling companions are drawn to him by circumstantial events(just being at the right place at the right time) and care for him because he's a decent(albeit not open about it) human being. The motivations behind the actions of the supporting cast are also largely unexplored and the people who are vile seem to be so for the sole purpose of being assholes and the people who are contradictory do so for the sake of forced conflict. This falls in line with that "anime logic" I addressed in the previous paragraph.
Art wise, I don't have much an opinion. There is CG occasionally that may appear distracting but at this point in time, there are very few animes that don't make use of it. It'll get better as time goes on. For the moment, I just accept it as it comes. I actually was impressed with the character design because, while some of it is a little over the top, there is no blatant fan service in the characters' armor and clothing choices. This isn't a novel concept but it's rare enough for me to give a nod to it.
Overall, The Rising of the Shield Hero will not go down as one of the greats but if you're just looking for something to sink time into, it's not a bad choice. If you can look past the anime logic you'll find an entertaining story about an underdog that doesn't give up.
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