Psychological quality training of special forces

I will. Some troops will give a player a bullet and let him spend the night alone in the wild grave. And his nearest companion is just another chaotic tomb more than ten kilometers away from him. In order to train the psychological quality of the players. Vietnamese special forces will put the team members into a 200-meter-long snake pool with thousands of poisonous snakes, and let them cross the snake pool through the skills they have learned. There are really many others, most of which are to put the players alone in places that make people feel horrible, exercise them and let them overcome their psychological fears.