Weird Stories About the Rules of National Destiny: Starting from the Cage Tower

A year ago, strange "doors" appeared out of thin air all over the world. Any country that steps through the door will have its national destiny value bound to the challenger team. If the challenge is successful, the country will be prosperous; if the challenge is failed or the rules are violated, natural and man-made disasters will be punished. This has become the "second battlefield" that Blue Star countries fear and rely on.