Meltan

メルタン

Meltan is a small Pokémon featuring a silvery body composed of liquid metal. Its head is hard and resembles a golden hexagonal nut, containing a small black sphere that floats inside and serves as its eye. It possesses a red tail that looks like an electrical wire, ending in two tiny protrusions. Official concept art indicates that Meltan's liquid body consists of gallium, allowing it to shed gallium tears. Its arms are capable of stretching to become longer or shorter.
Meltan's body corrodes various metals, which it subsequently absorbs and consumes. These absorbed metals circulate within Meltan's body to generate electricity, serving as its energy source. Meltan can also utilize this electricity for attacks by firing it from its eye. According to Professor Willow, Meltan is described in ancient texts discovered in the same location as the Mystery Box, a mysterious item that attracts Meltan to its position when opened. Professor Willow also notes that Meltan is said to originate from small shards when a Melmetal rusts and splits apart. Meltan is known to live in groups, until a day arrives when one strong Meltan absorbs the group to evolve into Melmetal.
As depicted in the anime, the hexagonal nut on Meltan's body can be removed. It has also been observed working in packs. When provoked, it spins its head, producing a sound that summons others of its kind. This head-spinning can also serve as a sign of affection. The anime further shows that Meltan can be tamed if fed metal-like treats, and its numbers can multiply over time. Meltan ranks among the smallest Pokémon, tying with Alolan Diglett and Klefki as the shortest Steel-type.
Evolution
Meltan evolves into Melmetal.