MTL - Manga Guidebook - ~ Explain and ask once

In a world fraught with innumerable dangers where living day by day is a struggle, a young man from the modern age transmigrated into such a world, accompanied by a peculiar system made for assassination.

One moment, Luo Jing was at the brink of death after accidentally touching a power outlet while showering. The next, he was in the body of a man named Garen, with memories of a past he was never a part of flowing into his head. As he slowly gets used to the body of Garen, he begins to explore a planet beyond his own logical comprehension. His journey will see him go from surviving in a planet locked in the 20th century, to wielding secret techniques so powerful that they level cities overnight. However, his journey doesn’t end with Garen. Instead this is but the first of many bodies that Luo Jing will come to wield in his mystical journey between worlds.

The engagement of the most adored daughter of the Li Family was broken off. Her furious family members railed against the heartless man and vowed to make him pay the price. * Later on, Li Qiao met her ex-fiancé’s big brother by chance. Some said he was the most mysterious man in Nanyang and his name was Shang Yu, aka Shang Shaoyan. While some others called him the overbearing and obsessive underground Overlord of Nanyang from whom everyone should stay away. Standing in the misty rain, Li Qiao gazed at the ruthless and untamed man with a shallow smile, said, “Hello, I’m Li Qiao.” She would become her ex-fiancé’s sister-in-law, if not wife. * Li Qiao and her ex-fiancé met again on the street several months later when he sneered at her, “Are you following me? Haven’t you given up hope yet?” A harsh voice berated him from behind, “Show some respect to your sister-in-law!” From now on, only one rumor was circulating in Nanyang City – The merciless Overlord of Nanyang had one woman he uncritically doted on. Her name was Li Qiao.

A world full of magic and wonders, where dragons stand for metals, sprites stand for farming, knights cultivate qi, mysterious wizards dwell. In this world, a man who had transmigrated into the body of a baron, follows the prompts of mysterious symbols to change his destiny.

- Description from Novelupdates