The Sunset Color symbol from Mystcraft controls the colors displayed when any sun or moon rises or sets. It takes a Gradient modifier, for which the total duration is set to the length of the sunset effect. It is normally a modifier for any normal sun or moon. However, if found "dangling" at the end of the book with no sun or moon found after it to describe, it has a small chance of setting the default sunset colors, for all suns or moons without their own sunset colors. Normally, it will simply cause another normal sun or normal moon to be generated, as those are the only primary variables that can accept it.