MTL - Hail the King - ~ 1168, Star Battlefield

Lugh woke up to find that he had transmigrated to a hundred million years later.

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates

Anastasia Harrison, a young woman abused by her cruel family, thought her life was over when they forced her to marry Richard, the sleazy black sheep of the wealthy Wallace family. Meanwhile, her favored younger sister, Michelle, was set to marry Xavier, the elder brother, who was a CEO.Yet, an error at city hall ended up swapping their names on their respective marriage certificates.“What is this?! How are you married to Xavier Wallace?”“You're not getting any food or water until you sign the divorce papers!”To add fuel to the fire, the old Mr. and Mrs. Harrison passed away, leaving all their assets to Anastasia and not the rest of the family. This drove the Harrisons to their breaking point. To trade for a peaceful life, Anastasia was willing to leave her inheritance and leave the family, but the Harrisons had other plans in mind.They wanted to get rid of her. Permanently.However, it was by a stroke of luck that Anastasia was found by her new husband, Xavier, before her family succeeded. Determined to get her revenge, she struck a deal with Xavier.“Continue to be my wife and I will help you get your revenge!”

The world is terrorized by the powerful Black Witch who has been sealed in the moon. Every ten years, the night of Hexennacht arrives and a chosen witch must battle the Black Witch in hopes of finally defeating her.

As the current decade’s Hexennacht approaches, a mysterious girl named Kagami Kagami arrives and meets Horinouchi Mitsuru, the daughter of the previous Hexennacht representative.

It takes place between Kyoukai Senjou no Horizon and the City Series, two other series by the author.