MTL - Record of Mortal’s Journey to Immortality: Immortal World - Chapter 8 Shiraishi

An orphan dies while saving a bus full of children. For saving countless lives, the Universe grants him the opportunity to transmigrate to another reality.

There he realizes his dreams of supporting his new family and opening a company that will shake the foundations of this new world. He will be known as the MasterChef of the gods, a superstar singer, the best Mangaka to exist, the best Director, the businessman of the millennium and many other adjectives.

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

In a monstrous post-apocalyptic setting, this is a story of how a lowly Inventor, Lance, conquered a nation governed by immoral group of Scientists called The Corporation. He grew and climbed up to the highest rank possible as a Scientist with his inventions and side businesses. Eventually, he became a weapons inventor, building weapons to two opposing sides. In doing so, Lance always crossed a dilemma. How could a nobody topple the most powerful government? How could one overcome circumstances beyond his grasp, especially in a world filled with monstrous mutations called the Abominants?

In a world where strength determines one’s future, William, an orphan with no extraordinary talents, faces a grim destiny—until a brutal attack leaves him clinging to life. Instead of death, he awakens to a mysterious and powerful entity lurking within his mind: the Shadow System, a game-like interface that promises him unimaginable power. But this power comes with dark secrets, and refusing it would mean his death. Forced into a pact with a voice that can hear his every thought, William must navigate a dangerous new reality where shadow abilities and celestial power collide. As he enters the prestigious military academy, his newfound abilities draw both allies and enemies, all while a deadly conspiracy brews in the shadows. With the odds stacked against him, William must unravel the mystery of the Shadow System and decide whether to embrace the darkness within—or be consumed by it. His journey from a bullied outcast to a potential god will challenge not just his survival, but his very humanity. Power always comes at a cost—will William be able to pay the price? “What am I?” William asked the system. The system’s voice echoed in his head, cold and indifferent. “You are nothing.”