There is a legend that has been passed down to this day: During the prosperous period of the Mayan civilization, the Mayan nobles made thirteen crystal skulls and gave them to thirteen families for their protection. As long as these thirteen crystal skulls are gathered together, the mysteries of the universe can be unlocked, and all living creatures on the earth can even be saved.
However, over the past five thousand years, these thirteen families have all lost their crystal skulls. And a secret organization called "Enigma" suddenly appeared in the past fifty years. The members quietly carried out the task of collecting Crystal Skulls, and their ultimate purpose was unknown...