During filming when Nathan Jones was to pick up one of the extras and toss him to the floor, Jones got too much into the spirit and the extra ended up going to the hospital with cracked ribs.
Nathan Jones took a fall badly during filming and almost lost several teeth. He refused medical attention and kept filming.
Brandon Rhea insisted that the long stick weapon, known as "mao", be equipped with a proper sharp point, else it'll look strange. He demonstrated his accuracy by having one of the extras hold a stack of newspaper three meters away from him. He did one lunge and thrust the point straight through the middle of the stack. Even Woo-Ping Yuen was impressed.
Nathan Jones is so large (he is 6' 11"), and the beds in Chinese hotels so small, he had to fit three beds together.