This Brave Man Was Once the Devil

In the first life, Ephedos, who was reincarnated as the Demon King, inherited all the heaven-defying abilities of the previous Demon King, as well as the last remaining lifespan of the previous Demon King. He made painstakingly hard medicine, just to seek immortality and maintain peace among all races in the outside world. Little did he know that once he made the wrong medicine, he died in the alchemy room. In his second life, he was reborn as an ordinary warrior of the human race, but finally reaped the late harvest of the system. In order to continue the peace of all races, the Demon King Ephedos embarked on the path of adventure again.