All the actors and actress were trained in Thailand for gun and unarmed combat one month before shooting. The crew hired a Thai royal body guard and a Class A marksman to train the actors. Eddies Peng was so obsessed with the training that he took a prop gun back to the hotel to train himself everyday. Peng's assistant described him as a "psycho."
The uniform Hanyu Zhang wore weighed more than forty pounds. At a press conference, he joked that he would be scared to death by seeing that kind uniform again because it already exhausted all his life's sweat.