MTL - My Two-sided Cultivation: Starting From Collecting Experiences - Chapter 66 I can use this killer move 3 more times!

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

Alvin had planned his future: after leaving the city of Serinthia and obtaining his graduation certificate in technology, he would return to his hometown, stay close to the only girl in his life, and kill a few people from time to time for fun and entertainment.But fate had other plans. On an ordinary day in the Royce Empire—one of the three great empires that ruled this world—the sky split open and a barrage of meteors descended. From that moment, the world changed, and the lands of the empire turned into a battlefield, as monsters appeared and people became hunters.Now, Alvin found himself forced to abandon his former dreams and return to his city before the companion of his life dies.

The consciousness of a Great Magus suddenly returned to his original body on earth, just before he transmigrated into the magic world.

Nothing has changed, it's still the same earth.

However, when he looked at earth once more as a former great magus, he discovered earth was not as simple as he knew it to be.

Hidden magus, legendary races such as vampires and werewolves, they do exist, ruling the world through the shadows.

Faced with a former great magus, who possessed as many spells as libraries, would the earth that had been ruled by a few people be able to remain calm?

She was a medical expert, talented and beautiful. She was reborn as his little wife. Her in-laws did not like her, her husband did not love her, and she was as timid as a mouse. She was weak and easy to bully.