Strongest Survival by Otome Game’s Heroine (LN) - Vol 4 Chapter 7: Dungeon Exploration Floor 70

The objective was the World Domination.

108 Demons and their Dungeons descended upon the land as they battled each other to become the Strongest Dungeon Master.

Isaac Constantine, a Demon Baron who managed to survive until the end of the game, only to meet betrayal that lead to his death.

Just as he thought it was over, he received a second chance

[Artefact Sand of Time has been activated.]

[Players can restart the game.]

[Synchronizing…]

[Displaying status]

[Isaac Constantine - Rank 99]

The battle between Dungeon Masters has restarted!

With a thirst for revenge, Isaac swore to create the best Dungeon and the Strongest army to win the game. Demons, Monsters, Superhumans even God himself will know his name.

Follow Isaac's story as he Rebirth to become the strongest Dungeon master

At some point in the 21st century, the Christian God stopped listening to the prayers of humanity. Monsters with colossal strength and endurance began to emerge and humanity entered its darkest period.

The end of all worlds approaches.

The Demon King Order harvests lives from all manners of living beings.

Within this darkness full of despair,
A single person escaped from space-time, returned to before the world collapsed, determined to change the fate of the past.

But as time pass, he gradually finds out that the Apocalypse isn’t quite as simple as he thinks…

- Description from novelupdates

Xia Yan passed through to the world of Bleach and became an eleven-year-old boy. He was rescued by Renji and Rukia in the Seireitei, and he was studying at Shin’ō Academy, and he was a student of the same class.
He is a top student of the Shin’ō Academy, and he is vying for strength by various teams. In the end, he has entered the first team of secret mobile maneuvers.
He will use punishment to kill every person who tries to threaten the martyrdom and protect his loved one.

- Description from Novelupdates