This anime is loosely based on the Zodiac Race. Is it worth your time? Definitely. Are you looking for a traditional Battle Royal anime? Then this is not for you.
Story:
The plot is what you will expect from a battle royal anime, but this time the focus is less on who is going to die, and more of a brief study of the aspirations and mindset each participating character has in this event. In that regard, it's also less about the battles themselves and more about the history and hubris of the characters; and in what way would it lead to their fate. If you are aware of the Zodiac Race, or have seen the first two episodes, then you would know immediately in what order each character will die. Juuni Taisen also heavily utilises tropes of irony and poetry.
Animation:
The combat scenes are well animated, despite not being the main focus. And the animation on a whole is consistent. There is one particular episode where the quality dipped lower than what's usual for this anime, but it wasn't to the point where the anime suffered. Computer generated animation was used in place of the more common 2D hand-drawn animation in that episode, but it was done in a way that it didn't matter.
The art for the characters are well-done as well. Each character has their own distinctive look and are easily recognisable from each other. They also have their own special way of walking and running, which helps sell each of their personalities. The background art doesn't stand out, and works how it was intended.
As for the sound direction, there aren't any particular standout soundtracks. There is only one piano track which stood apart from the rest. Otherwise, the opening and ending are standard fare.
Overall, you will find enjoyment out of this series if you have more interest in learning the history of the characters and wondering how they'll die, rather than musing about who will die.