Jiang Liuer (whose real name is Chen Xuanzang), whose Buddhist name is Tang Monk, was in his previous life the "Wudao Zhenren", a master in a certain world of immortality who was in the tribulation period. After the tribulation failed, he was pulled into the world of Journey to the West by the system and possessed the newly born Jiang Liu'er. The system forces him to "play" an ordinary monk - he must pretend to be weak in front of others, otherwise his merits will be lost. So even though he can kill the Bull Demon King with one punch, he still has to pretend to be a weakling who can fall down in front of Sun Wukong if the wind blows.
