The First Demon of the Chan Sect - Chapter 268 - 214 Defeat the Enemy in 30 Moves

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

Aric Valerian, the fourth prince of the Valerian Empire, bears many titles: The Forgotten Prince, The Whore’s Child, The King’s Bastard—names that have been spoken more than his own. Born with a crippling illness and devoid of mana or ki, Aric was a disgrace, scorned by his family and the court. But when the gods cured him and gifted him the strength to fight, Aric dared to hope. He sought glory in battle, only to be betrayed by his brother and sent to die in a hopeless war. In his final moments, as death closed in, a mysterious text appeared before him… [Would you like to change your fate?] After being given another chance, Aric embarks on a ruthless journey to claim absolute sovereignty. [Ki Circulation Mastered: Strength +10] [System Upgrade: Advanced tactical planning unlocked] [Hidden Fortress Established: Stronghold security +15%] The forgotten prince claws his way through the treacherous landscape of imperial politics, he is forced to make impossible choices, each decision pushing him further down a path soaked in blood. He learns that true power demands sacrifice, and the price of vengeance may be his soul.