Zankyou No Terror aka Terror in Resonance is definitely one of the best animes to watch. Personally, I really liked the show.
The anime is brief with a total of 12 episodes. The story is great and it is good enough to keep you hooked during the time you watch it. The characters are great and their lives really touch you on an emotional level.
I feel the story was quite unique and the anime is truly one of a kind. I recommend watching the series as it is short and will entertain you for the time that you watch it. It is quite fascinating how the main characters are so devoted to their cause and are willing to sacrifice so much to achieve their goals. In a way, they had no choice but to do what they did and what the anime teaches you is that you can always make a difference if you choose to.