Revered long ago for its capacity to create iron from nothing, for some reason it has come back to life after 3,000 years.
At the end of its life-span, Melmetal will rust and fall apart. The small shards left behind will eventually be reborn as Meltan.
Centrifugal force is behind the punches of Melmetal's heavy hex-nut arms. Melmetal is said to deliver the strongest punches of all Pokémon.