Romaji: Desumasu) is a species of Pokémon in the series of the same name. It is a Ghost type Pokémon that made its first appearance in the fifth Pokémon generation in the Black and White games. It evolves into Cofagrigus starting at level 34. Yamask also has an alternate form native to the Galar region. This form is a Ghost/Ground type Pokémon that will evolve into a Runerigus when the player travels under the stone bridge in Dusty Bowl after Yamask takes at least 49 HP in damage (even if healed) without fainting.
Yamask is a shadow-like Pokémon holding a golden mask that has a face from its time as a human. It has two shadowy, tendril-like arms and large, red eyes. It also has a small tail-like appendage that holds the mask. Yamask is capable of speech when possessing a human, but not in its regular form.
Due to being a human long ago, Yamask retains its memories from before it became a Pokémon. It becomes furious when the mask is lost or taken away. If someone wears the mask Yamask carries, they will become possessed by the Yamask in question. Sometimes, it looks at this mask and cries, apparently in longing. Yamask is known to wander the ruins of ancient civilizations.
Galarian Yamask[]
Galarian Yamask, in contrast to its Unova variant, has purple eyes and has an ancient clay tablet directly attached around its tail. Galarian Yamask is said to have been born when that tablet was drawn to a vengeful spirit. The tablet bears cursed engravings that resemble a serpent's tail and is said to absorb Yamask's dark power. This process, brought by an ancient curse, triggers Galarian Yamask's evolution into Runerigus.