My starting summon is a small skeleton - Chapter 352 - 349 Divine Wrath

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.

Doomsday Online has descended, reducing the entire Earth to a ruined playground. It is occupied by countless terrifying monsters.

When waking up, Jiang Tian found out that it was not too late.

In his previous life, Jiang Tian was a member of Jiang family in Jinling. He suffered a disgrace that was his fiancee broke off the pledge of marriage, so he had to marry into the Zhao family. Although Zhao Xueqing, his wife was the first beauty in Hangzhou, he always beat and scolded her. A few years later, he went through a family upheaval, and his loved ones died one after another. With despair, guilt and hatred, Jiang Tian jumped from a cliff. But he did not die. Instead, he started a cultivation journey for as long as ten thousand years in another space.

He became the supreme god, but he died in the process of opening up the universe. With the regret for his parents and the guilt for Zhao Xueqing, Jiang Tian, who retained several thousand years of memory, swore that he would never let his loved one suffer any grievances and injuries this time!

- Description from Novelupdates

In a modern world, a professional assassin was murdered by her beloved and found herself revived in an ancient world as a general’s daughter with a weak physique. She was engaged to a prince, but because she did not have a nice appearance, her fiancé and sister attempted to kill her. Although she had to struggle to survive, there were also those who unconditionally loves her that supported her in her time of need.