Isekai de Kojiin wo Hiraitakedo, Nazeka Darehitori Sudatou to Shinai Ken (WN) - Chapter 66: The New King.

In the endless Universe is eight primordial laws. Each of the eight laws have been fused with a supreme expert, but unbeknownst to everyone, there is a ninth law in the universe. It tears open the Primordial Chaos and is beyond reach.

Di Jiu—whose name is a homophone for ‘ninth’—is the ungifted son of a powerful Di family clan in the Ji Nation as he lacks martial roots. Unwilling to resign to his fate, he practices medicine, hoping to one day cure himself.

- Description from Novelupdates

Transmigrating into a poor and mistreated young lady's body, what will the craziest alchemist of the seven realms now do?

The whole world mutated. Mysterious resurrections happened in real life. The Tribulation descended.

Theatrical regression life of an old-fashioned villain (kkondae) who recalled his past life.

“There’s nothing I wouldn’t do for a better life.”

——

Survival in the ‘Otherworld’; a place where only the insane can set foot in.