Nidome no Yuusha - Chapter 165 - Prologue 2

As the last abyssal demon in the world, Wen Long was pulled into various worlds to do tasks by a guy who claimed to be a system. The goal of her mission was to save those villains who had been blackened for various reasons…

- Description from Novelupdates

Civilization is destroyed and records lost. Only Dudian survives in a cryogenic sleep. Three hundred years later, Dudian wakes up and must become Dean to survive. Who can he trust in this world overrun by monsters without and within?

Emperor Ian Veroshion, the first noble mage, was betrayed and executed. Cursed to never be reborn, he awakens a century later as the illegitimate son of a disgraced ducal line, destined to be a hostage in a barbaric land. Stripped of his magic and his throne, he must navigate a world vastly different from the one he ruled, facing political machinations and a resurgent monster threat. But the embers of his past life still burn, and Ian will not surrender his legacy. He will reclaim his name, his magic, and perhaps, even his empire.

A Pill Emperor of his generation was set up by a traitor.

Since then, the world lost a Qingyun Zi and gained an invincible silkpants.

Once again, walking the Great Dao of Alchemy.

How can I defy the heavens . . . with the medicine in my hands!