MTL - Those Years When I Was Cannon Fodder - Chapter 824 talk about it later

A man who was once called the world’s strongest agent ended up becoming a teacher after his retirement, to train a new generation of agents. After many years of training his disciples, he was killed at the age of 60 by a secret organization’s ruse and was reincarnated in another world with his memories intact. Though he was surprised by the existence of magic and the strange species in that world, he quickly adapted to his condition as a newborn and took advantage of it. He acquired special magic and gained a massive amount of strength thanks to his rigorous discipline, in order to reach his goal: Resume his career as a teacher which he left halfway through in his previous life. This is the story of a man, who, based on the memories and the experiences of his previous life, became a teacher who travels through the world with his students.

Princess Leah wrote a suicide note ahead of her wedding.

I finally managed to kill the demon lord.

This is a strange and inexplicable world…Mountains, water, stones, flowers, grass, trees, wood, the Sun, moonlight, stars… All creation under the Heavens and Earths are sources of energy. In this world, there are all the classics from his previous world, but there is a new addition: The Law of Dao. Fang Zhengzhi was conflicted. I can obtain power from reading books? Should I read Tao Te Ching first? Or should I read The Art of Becoming Invisible? What about the Analects of Confucius or… The Golden Lotus? With The Law Of Dao as his foundation, can Fang Zhengzhi master the Dao of All Creation and open the gate of God?