The alien Gauna may have destroyed Mankind's original home, but aboard the asteroid-based spaceship Sidonia, the human race has found ways to adapt, change and survive in the endless depths of space. Now the former people of Earth can photosynthesize like plants, a third gender has been created, and military service is mandatory. Because what could be man's last battle is about to begin, and the survival of our species will require every resource humanity has left. That includes Nagate Tanikaze, who carries a secret buried in his past that could change the course of destiny. Unfortunately, the Guana have their own new tricks as well, and not all of Nagate's allies are who he thinks they are! The ultimate war of the worlds is about to be waged in KNIGHTS OF SIDONIA - The Complete Collection!