For the Glory of Rome: Chronicles of an Isekai'd Legion - Epilogues: Mage, Entity

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

A young juvenile’s dantian was sealed since childhood. He can learn all elementary laws and master all martial art techniques. Various Kings strive to reach the heavens, new warlords rise together simultaneously, great races stand with thousands of numbers. From the moment that youth awakens, Everyone will shiver in his presence…….Humans unfair to ME, millions of corpses on the ground.

HEAVEN IS AGAINST ME , MY FURY WILL BURN THE HEAVEN ITSELF…….

- Description from Novelupdates

What does it mean to be invincible?

Many Sword Gods exhaust their entire lives attempting to cultivate a single supreme sword intent, yet Yang Xiaotian has cultivated fifteen!

For millions of years, no one has been able to cultivate the Primordial Heaven Destiny, but Yang Xiaotian has cultivated fifteen of it!

Throughout countless eons, no one has been able to cultivate the Primordial Universe Holy Fruit, yet Yang Xiaotian has cultivated fifteen!

Across the vast expanse of time, only the rulers of heaven and earth could cultivate the Eternal Divine Body, yet Yang Xiaotian has cultivated not only the Eternal Divine Body but also the Primordial Heaven Destiny Divine Body, the Primordial Universe Divine Body...

This thought had grown deep in William’s mind!