How come the celestial technique I stole is so powerful?! - Chapter 367: Beneath the Azure Waves, the Submarine

Side story of Kyoukai Senjou no Horizon bundled with the first press release of the 1st, 3rd, 5th and 7th Blu-ray volumes of both seasons of anime.

This side story follows Asama, Kimi and Mitotsudaira aboard Musashi one year before the beginning of the main story, as Asama is considering to create a music band together with her two friends for the next festival in Aki, a territory under the governance of K.P.A. Italia.

The main character Lei Yu does not have the ability to practice his family’s martial arts. He gets stepped on and tossed around. Due to certain reasons, he leaves the family, coincidentally gains an ability, and makes his own path to becoming an immortal.

- Description from Novelupdates

Outer yard disciple of the Tiansang Spirit Palace, Xu Xiaoshou, had average talent. However, after coming out of his death seclusion, he realized that everything had changed. He had received a Passive System with many strange, miraculous passive skills: He would become stronger with every breath. He would become stronger when he got attacked. He would become stronger when he got mocked… Xu Xiaoshou was forced to shout, “Oh God, I don’t want to be like this either. Everything I did was because I was being forced to! I am so passive!”

Zou Liang, an otaku with a passionate interest in a fighting game came into a world governed by the beast tribes.

There the ones with high martial ability were respected.

Extreme beauties were a little silly.

This guy felt depressed. Such a crazy really could force a civilized people like him to turn crazy!

Scoundrel Zou began his unrestrained and destructive journey in the Beast God Continent.

Rules? There are no rules!

Principles? His actions defined the principles!

Occupations? Occupations were as unimportant as fleeting clouds. What he sought was omnipotence!

In a different world, Zou held the same passion.

This is a story of a nobody becoming the great conqueror—step by step—as a human, filled with touching emotions, explosive anger, and hot blood forever!

- Description from Novelupdates