Isekai Maou to Shoukan Shoujo no Dorei Majutsu - Volume 1 Chapter 2.12

Lachlan, once a victim of deceit and betrayal, wakes up to find himself back in his high school days, just before his life took a dark turn.With a newfound system that grants him immense knowledge and skills, Lachlan vows to change his fate and protect his love, Julius. As he navigates through old rivalries and new opportunities, will Lachlan succeed in rewriting his destiny and exposing those who wronged him?

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!

- Description from Novelupdates

Ukei Kaito fought a desperate struggle in order to fulfill his role as a summoned hero. He defeated the Demon Lord and saved the very world, only to meet an end filled but with betrayal. The companions that he’d trusted throughout his journey betrayed him and killed him by sticking a blade through his chest.

He transmigrated and got a system but Lin Feng’s pressure is as big as a mountain.