Bloody hell.

Guy with big sword killing just about everything, following the rise and (bizarre) fall of a clan.

If you have only seen the anime, that might be the only impression. But there is a lot more psychology and politics involved to make this a very interesting series. It's still very bloody, of course ;)

Fans of the manga will be pleased to know that the anime followed the manga very closely, although watered-downed quite a bit (and the few moments of humor have completely disappeared). Unfortunately, it was abruptly cut off around volume 14 or so. Perfect for a second season ^_^;;

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