Some Pokémon may appear in different forms during certain weather conditions or in certain regions. These Pokémon have some differences comparing them to regular ones of the species, such as different types, moves, base stats and height and weight.
In case of Unown, there are no different types, moves nor statistics among any of its forms. Each of these forms resembles other letter of Latin alphabet with addition of exclamation and question marks.
There are currently eight different patterns for Spinda and additionally eight another different patterns for its shiny variants, which gives total of sixteen different patterns for Spinda.
On May 22nd, 2018, Alolan forms of Pokémon, originally discovered in the Kanto region, were stated to begin to appear in-game.[1]
Some Pokémon such as Pikachu, Raichu and Sneasel are sexually dimorphic, meaning that they possess minor differences in appearance between males and females.
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