High School DxD - Volume 20 Chapter 5

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

This is a young man who traveled to the world of Azeroth.

For love and justice (don’t become a ghoul), fear of sacrifice (you can run the corpse to resurrect), in search of lost justice and humanity (temporary discipline), don’t stop.

Festival Exercises Retrieve the story of Festival Exercises.

- Description from Ptwxz

One of the Conferred Martial Emperors, Gu Feiyang, passed away in the Tiandang Mountains and was reincarnated 15 years later as Li Yunxiao of the State of Tianshui, embarking on a heaven-defying journey against the innumerable geniuses of the time.

The nine levels of the Martial Art; the Divine Realms of the ten quarters. From then on, the whole world fell into chaos!