MTL - Eternal Heart - Chapter 54 Outer door number 1

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.

I dedicated 10 years of my life, focusing solely on regression.[Authority: Death Regression has naturally been nullified.

He approached her and announced domineeringly, “Ten million, you're mine!” Little did he know that she would smash his head and flee in panic! Five years later, for the sake of her young son, she endured humiliation and became his wife, always on guard around him, “Get out, what are you doing coming in?” His handsome face darkened, “Woman, you couldn't have forgotten that we are husband and wife, could you?”

A guy became a brother of Iron man and got the ability to extract genes from anyone. Lets see how he changed the Marvel World

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