Smelting (精錬, Seiren) is Quirk that allows the user to turn their body into a blast furnace and melt metals inside it.
The main strength of this Quirk is the ability to solidify the molten ore in the user's body and shape it into anything the user desires, including metal weapons. The user is also able to launch the extremely hot molten ore out of their body to attack others. They can also turn people into solid silver statues. They are also granted immunity from being burned by the molten ore and the initially hot metal it is formed into.
The user requires a supply of ore inside them in order to be able to form weapons, forcing them to constantly consume ore in order to use the Quirk.
The user of this quirk is given unbreakable teeth and is capable of consuming ore and other metals to fuel their power.