Sword Guards the Great Wall of Humanity

The system made me beg in the human world for twenty years. After twenty years, it would give me the cultivation of a swordsman. However, I was brought back to the sect for adoption by a lame old man in the Jindan realm. "Master, please let me go out to beg. In two years, I will be the current swordsman." "No." "Why?" "Because I am the master of swordsmanship in this world."