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I really enjoyed this anime. It was many things really. Take for instance the violence. Not really gruesome violence but bloody and quick. A lot of people came and went and died, including main story characters. Then there is the story. I do not know what the producer of this anime did but this was one of the most well paced stories I have ever watched.
As far as the story goes I believe there are three arches. Zwei's training, Zwei's reign is what I will call it, and Zwei's escape. There was very nice balance in this story that I have never seen in other anime. I cannot describe it. There were not too many cliffhangers and the story never felt rushed or umm the opposite of rushed.
The story flows very smoothly. Even the jumps in time flow very smoothly into each other. After watching this anime I did not feel like I had spent only a couple hours watching 26 episodes. It felt more like I had watch closer to 50 ro 60 episodes. I do not know what the writers did. It was probably the short action sequences.
I really liked that about this anime. The action was not slow at all. I mean slow in many ways, slow as in not much action at all and slow as in the fight drags on forever. Most every fight was resolved quickly. Very rarely did a fight go on for longer than a few minutes. Even better when people were shot they generally stayed down. Which kept the fights from getting out of hand.
Probably my favorite part about this anime is it is a tragedy. To be honest I have not seen many animes where there is a very tragic story line. Most anime tells a story that is happy and uplifting or at least ends on a good note of some kind. The tale that is told is sad, that makes it very watchable. Maybe I am a masochist, but happy endings and happy go lucky characters only do so much for me.
Overall, I would definitely recommend this series to anyone and everyone... who can comprehend what is going on. As well as can accept that the hero..s are tragic. So pretty much everyone needs to buckle down and watch this anime.