What does it mean that the son of the ancient king and Xu Sanshao bet on six colors?

In the early Qing Dynasty, a descendant of the Xu family named Xu Shupi wrote a book "Xiao Zhi Record", which recorded the ins and outs of his uncle's cheating on the Humble Administrator's Garden, and let the descendants know the truth of the first change of doors in the Humble Administrator's Garden. It is said that Xu Shaoquan bet Wang's son with 1200 silver at that time, and agreed that the person who scattered bones at six o'clock would win. After gambling for a long time, when he was about to lose, Xu Shaoquan invited prostitutes to drink and play instrumental music together. When he began to get tired, Xu Shaoquan asked him to bet in the Humble Administrator's Garden and secretly took out a six-dividend skeleton and threw it over. I saw that the six points on the skeleton were all red, and everyone here shouted in surprise, because it was generally impossible. Wang's son didn't know that he was cheating. He was disappointed and couldn't say a word, so the Humble Administrator's Garden lost to Xu Shaoquan. Later, Wang, his son, was devastated and his family came down. When he was a grandson, he was too poor to make a living in mourning.