A Professor of Magic at Hogwarts - Chapter 4: Felix’s Theories

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!

- Description from Novelupdates

Lilian laid on his deathbed, his life nearing its end.Surrounded by the cold quiet of a hospital room, he had spent his last months immersed in novels on his phone.One novel, in particular, had captured his heart, and he yearned to finish it before succumbing to his incurable disease.But as the end drew near, he realized he couldn't access the final volume.Helplessly, he regretted the opportunities he had missed in life.And death had finally come knocking.“If only there were another world... that could offer me a second chance,” He whispered.“If only I could live a second life... in a time when I had listened.”

Reborn in the cultivation world, Gu Feng becomes the most useless member in the history of his family!He creates the [Shared Flying Sword]!Establishes the [Immortal Sound Live Broadcast]!Initiates [Cave Heaven and Blessed Land Development]!Promotes the [Digitalization of Spirit Stones]!Founds [Qi Refining Local] and [Dao Companion Online]...In a world where people are the knife and he is the fish, he faces daily cunning schemes and crushes the arrogant geniuses!Cultivation starts from squandering... Gu Feng forges an entirely different path in the world of cultivation...

The latest offering from the pen of the creator of “My Military Branches Can Evolve Infinitely”, Bimo Zhijian.---------------------------------------------The world has experienced a radical transformation. Source Qi has awakened and the apocalypse has descended.This is a catastrophe and also the beginning of a new epoch.Tang Yu somehow obtained a domain system, and while summoning warriors, producing equipment, developing his domain, drafting rules...as he looked back, he discovered that he was already standing at the apex of the era.