Wizard: I Can Synthesis Everything - Chapter 20 - Cooperation

Getting lost in a trip made Tang Siyu be mistaken for streetwalker, and she lost her wedding night. After returning home, she found the fiance cheat her with her sister. She cancelled the wedding in anger and declared missing.

Five years later, she came back with her gifted son. Unexpectedly, her baby took part in the piano competition in order to find his father. “My name is Tang Bao, my mother is Tang Siyu who is super beautiful! I am four and a half years old this year. If there is a man who looks like me may be my father. Please contact me! ” Behind the scenes, a woman was mad. A few days later, the mysterious man called himself the father of her child. Tang Siyu looks at this tall and handsome man who looks like her son. She is angry. So, he was the bastard five years ago?

5 years after the world changed, the final boss appeared.

A teenager named Evan Mason was reincarnated into the magical world of Harry Potter and goes to school at Hogwarts!
With only his knowledge of the future and great talent for magic, he takes the path towards the top of the magic world, only to realize that ever step he took, changed everything!

- Description from Novelupdates

After crossing over into a world of magic, Dean Bruce was mistaken for a powerful sorcerer. Though he initially intended to sternly refuse the beautiful woman’s request to become her mentor, she offered him far too much to say no!Completely clueless about magic, Dean Bruce had no choice but to make up spells on the spot. However, when he saw the astonishing power unleashed by the beautiful woman after chanting his random incantations, he was stunned.The spells he had carelessly invented… could they really comprehend magic and even forbidden spells?As Dean Bruce ascended to the pinnacle of magical prowess and became the Archmage, he candidly answered a reporter's question during an interview with the Alliance: “ never understood magic. I just made up a few incantations, that's all.”People were in awe of him—this, they believed, was the true humility of a Grand Archmage!