Toaru Majutsu no Index - Volume 13, Chapter 10: Their respective battlefields. The_Way_of_Light_and_Darkness.

All I ever wanted was for famous detectives like Sherlock Holmes or Arsène Lupin to appear in my dreams and share their wisdom. But instead, why am I hearing the voices of notorious serial killers in my head, guiding me to solve a string of mysterious cases?

I, a mere con artist, was unjustly imprisoned in Tantalus, the Abyssal Prison meant for the most nefarious of criminals, where I met a regressor.

But when I used my ability to read her mind, I found out that I was fated to die in a year…

and that the world would end 10 years later.

The legend of the continent, the battle that brought fame; the Sacred Phoenix Lady, the Windfire Meteor Godrealm saber-art; the pair that ascend and fuse, the golden sun and the blue moon, the fury of the crashing thunder. There is no magic, no battle qi, nor any martial arts in this land. However, there are martial spirits. Ten thousand years have passed since the founding of the Tang Sect on the Douluo continent, and it has declined. A new, proud generation of heaven’s chosen has been born. Can the new generation of Shrek’s Seven Devils rally the Tang Sect and once more compose the song of the Unrivaled Tang Sect?

Kyoukai Senjou no Horizon chronicles the story of a futuristic civilization returned to Earth after constant warfare hindered them from traveling beyond the post-Apocalyptic Earth. At this stage, a small archipelago called the Divine States were the only hospitable land on Earth. In order to regain the space-faring technology they had lost after many years of war, they decided to recreate history with a book called the Testament as a guide.

It is the year 1648 in the Testament Era. Toori Aoi, Chancellor and Student Council President of the only academy on the airborne city-ship Musashi, faces the ten-year anniversary of the death of his childhood friend Horizon Ariadust in an accident. As he prepares to celebrate the occasion by proposing to P-01s (an automaton who looks exactly like Horizon) he discovers that his suspicion about P-01s’ appearance actually has a basis in truth; P-01s is in fact Horizon Ariadust, reborn into a robotic body. In addition to this, Horizon’s emotions had been stripped away and are now stored in eight powerful weapons called the Mortal Sin Armaments; which are now in the possession of key people in various established countries in the Divine States.

To retrieve the emotions of Horizon Ariadust, Toori Aoi along with his friends and allies begins a crusade against different obstacles as key events in history are recreated in a futuristic manner.