Le Loi's exploits to repel China's Ming forces from Dai Viet (a territory that is part of present-day Vietnam) is well known throughout history. However, history often overlooks that his fiery will for freedom from oppression was also backed by the Will of Heaven. Le Loi and his rebels did not fight the Mings alone. The magic sword called Thuan Thien—a loan from the Dragon King, Long Vuong—played no small part in that victory.
Those in later dynasties would come to see this as fiction, but those who fought alongside Le Loi knew the truth. The sword of conquest was ultimately returned, since a weapon that powerful could not remain in the realm of humans. The remnant of that act resides in modern-day Vietnam at Ho Hoan Kiem, or the Lake of the Returned Sword.