I really wanted to give this a 10/10. But there were some things about it that are my reasonings.
The story is really compelling and interesting. But there were a couple times that it dragged on such as the middle of the York New city arc and (kind of) the arc with the ants. But overall worth the drag. A good thing about the story is that it hooks you straight away in the first couple of episodes. Major reason why it's not 10/10 for me is that they chose to show what happened to each character in 5 minutes at the end behind the ending song. I mean especially with the tease about kuripika (most likely misspelled) and Leorio not getting an answer.
Art- nothing outstanding, not crap. Not god tier.
Sound- for the first 30 episodes or so good op nice ending song, but then you realize they keep it for pretty much the entire show. I almost missed the resolution with the other MC's because they chose to do that behind the ending song. Should have had at least one other op. On a more positive note the Dubb is 10/10 in my book.
Characters- I really enjoyed and felt the characters on a personal level. I cried multiple times towards the end.
Overall- get your animu loving butt over to the web and watch this anime. It isn't #5 for nothing.
