According to the official Pokédex entry for first Mythical Pokémon added to Pokémon GO, Mew is said to possess the genetic composition of all Pokémon. It is capable of making itself invisible at will, so it entirely avoids notice even if it approaches people. Building upon this unique trait, Mew is capable of appearing nearly invisible with a translucent sheen in Pokémon GO, as shown in the new promo below. Mew can be yours after successfully completing the first batch of Research tasks in Pokémon GO.
Source: @PokemonGoApp
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