MTL - Black Tech Internet Cafe System - Chapter 320 How can I not use it?

I exist in the darkness, disappear under the bright light, and will eventually devour the sun and turn into the shadow of all things… Known by people as the indescribable terror of darkness; the king of shadows; the dark day; the existence of the shadow of the world , is still just a somewhat special high school student, facing a weird death game…

- Description from novelbuddy

Takahiro Nao, a 25-year-old burdened by crushing debt and driven solely by his love for his struggling family, meets a tragic end—until a mysterious Goddess of Benevolence offers him a second chance: reincarnated in another world, and his efforts there will provide for his family back on Earth. Awakening in the body of Naoki von Blackmore, a disgraced “Failed Hero,” Nao is thrust into a realm of sword and magic, monsters, and war, tasked with the impossible mission of defeating the Demon King. With newfound powers, a shadowy past, and the weight of two worlds on his shoulders, he must battle not only relentless enemies but fate itself. Blending emotional depth, thrilling action, moments of humor, and a spark of romance, this gripping isekai adventure asks: how far would you go—and what would you sacrifice—for the people you love?

He has been abandoned by his clan.

He has been considered waste from his childhood but he is a “Peerless Genius”.

His father with the help of another person has sealed his Dantian to stop him exposing his exceptional talent but after his rebirth, he becomes the most dazzling star of the continent. However he faces crisis and difficulties as his Dao goes against the Heaven’s will.

Overcoming everything, eventually he achieves the highest boundary “The God of War”.

- Description from Novelupdates

The girl submerged in the bottom of the lake suddenly opens her eyes. The noble ChuChao Gongzhu [Princess] becomes an abandoned daughter and woman. No problem. This type of slag father is not worth mentioning. By virtue of her exquisite medical skills, she becomes famous in the world. Slag father wants to reunite? Close the door, let out the dogs! Shizi [Heir of a noble title] wants to ask for marriage? Let him wait in line! The Regent has a chronic illness? Perfect. Godly doctor becomes a poison doctor. Let him neither live nor die and taste the pain of his evil deeds. She exacts bloody vengeance. Appointed Wuguo Gongzhu, she returns to her noble life. Slag father regrets, sister envies, stepmother hates!