Forge Release

Forge Release (フォージ遁, Fōton; Viz "Forge Style") is the secret chakra nature of orginally possesed by hephaestus with it he is able to manipulate Yin and Yang chakra to create various weapons and tools, by manipulating metals and earth. Hephaestus later passed this nature to Azusa Nakano after seeing that he had a knack for creating items.