The Reborn Evil Sword Emperor

In the Xuanhuang Continent, there are thousands of races and constant disputes. Among them, the three races of humans, demons and demons are the most powerful. Three thousand years ago, the three emperors of the human race came into being, destroyed the demon lord and killed the demon emperor. All races surrendered, the human race entered a golden age, dragon luck was prosperous, talents emerged in large numbers, and evildoers were rampant. . . . . . What kind of story will start when an extraterrestrial visitor comes to such a world?