I used any door to go to Nobita, and accidentally found the parts of the robot, but because the parts were too big, I took them to the mirror world with Doraemon for assembly. After the assembly, Doraemon named him "Christmas Warrior". When I was happily manipulating Santa Claus, I accidentally found him wearing a devastating missile ... In the real world, Nobita accidentally met Li Lulu, who claimed to be the owner of the robot, and borrowed props to enter the mirror world. But then Nobita and Doraemon discovered that the mirror world had built a base to attack the earth! The conductor is Li Lulu, who was originally a robot sent by Mechanical Utopia to guide the Iron Man Corps to the Earth. In order to save the crisis of the earth, the heroes decided to fight the Iron Man Corps. Because Li Lulu was injured and saved by Jing Xiang, it was wrong to discuss conquering the earth with Li Lulu. The Iron Man Corps can't wait to get in touch with Li Lulu, and they have all reached the earth on a large scale, so Nobita and them began to fight the Iron Man Corps in the mirror world. Li Lulu was also moved by Jing Xiang and seriously thought about his misconduct. So she and Jingxiang went to the doctor of anthropology. He created the ancestors of mechanical utopia at that time more than 30,000 years ago, in an attempt to transform the ancestors of mechanical utopia so that their descendants would not want to conquer the earth.