Dragon Waves are used in Alkahestry/ Rentanjutsu, the Alchemy of the country of Xing. We are first shown how Dragon Waves are used when Mei Chan throws Kunais (Japanese throwing knives) at a collapsing mine. The Kunais then make a transmutation circle on the mine entrance. Mei Chan then creates a transmutation circle with her hands where she is standing, without chalk or anything. She then performs Alchemy and rebuilds the collapsing mine, saving the men inside. Mei Chan did that by sending 'dragon waves' through the earth, from her transmutation circle to the transmutation circle formed by the Kunais.