MTL - Tech House System - Chapter 99 engineering mechanics

Year 2056, in a city in the Yuan Jiang Su Jin area. On top of a ruined, shattered six story residential apartment sits a teenager wearing a combat vest, militaristic trousers, and alloyed battle boots. On his back is a hexagonal shield and equipped is a blood-shadow battle knife. He sits there silently on the edge of the roof. At this time, the sparkling sky was shining and there was a refreshing breath within the air that blew towards him. However, there was only silence within the ruined, deserted city, with an occasional howl that makes your heart skip a beat.

- Description from novelupdates

He was The Greatest Talent in the Nine Hells Realm.

Shen Zhenyi began to practice his sword when he was four years and two months old.

At the age of seven, he studied the Ten Thousand Sword Sutra. By the age of eleven, he fought against the Yudao in Shangqing Palace. In an instant, he unleashed one hundred and eighty-five sword strikes, making it impossible for anyone to retaliate. The Yudao admitted defeat and deemed him as “The Peerless Genius.”

At the age of 14, Shen Zhenyi, with his Six Forms of the Ancient Sword, surpassed the swordsman Zuo Tianxing who was ranked among the top ten masters in the world, and won the title of “The First Swordsman of the Abyss.”

He now lies crippled. A fraction of the state he was in before. Or so they thought.

- Description from Novelupdates

Synopsis: Yang Chen, the inheritor of the divine throne of Hades, was separated from his family at a young age and sold to a foreign assassin organization. Enduring the darkest of worlds, he eventually returned to his homeland incognito. Intending to live a low-profile life as a street vendor selling lamb skewers, fate took an unexpected turn when he married a well-known local corporate CEO. Hoping for a quiet existence, he found himself drawn into the role of a guardian knight due to the presence of beautiful women from various walks of life. As he navigates through these connections, his past experiences and former comrades resurface. Inadvertently, he delves into the world of cultivation in China and uncovers the essence of this world.

The Yanhuang Ancient Domain, vast without end, gave birth to many Celestials and Demons of antiquity tore Heaven and Earth apart and surpassed the control of the 3 Realms and 5 Elements over the endless years it has existed. Numerous Gods, more than ten thousand races, and humans born with a God class body have also come out from the Domain, traveling through the nether, warping Yin and Yang, omnipotent.