Pokémon GO players have managed to catch more than 589 million Magikarp during the popular mobile title’s first-ever Water Festival. This massive figure includes Shiny Magikarp, which were added on day one of the in-game event. During the Water Festival, the Water-type Pokémon Magikarp, Squirtle, Totodile and their Evolutions to appeared more frequently all around the world. Additionally, players had a greater chance to encounter several of the Water-type Pokémon originally discovered in the Johto region.
Source: @PokemonGoApp
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