Transmigrating to the 80s to Become Stepmom to Five Bigwigs - Chapter 329 - Use this Chance to Get a Divorce

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

Reborn into a fantasy world of magic and aura, Rowan is the second son of a ranch family living boringly in a backwater village, with no magic and no inheritance.To avoid rotting away in the countryside, he becomes a mercenary instead. Better to die fighting than waste away.After his first kill, the Black Dream awakens: a power that lets him plunder abilities from everything he defeats.But it's more than that. When he fights alongside others, their techniques become his: a master archer's deadly precision, a hunter's supernatural tracking, an assassin's shadow-step…Every ally becomes his arsenal.Ascension awaits! From the lowly dirt to the throne of the gods.

Three Emperors have died in quick succession. The prince whom nobody had taken notice of unexpectedly succeeds to the throne. He is quickly plunged into layers upon layers of danger. The Empress Dowager dislikes him, wishing to install a younger, more obedient Emperor. His half-brother dislikes him, accusing him of stealing the throne that is rightfully his. The palace attendants and servants dislike him, believing that he is not a true Emperor. The Child Emperor must save himself.