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Across the different versions of Pokémon, Eevee has many evolutions. Is it possible to choose what evolution we get when we evolve an Eevee?
Umbreon when leveled up with high friendship during the nighttime (Generation II onward, excludes areas with a Moss Rock or Ice Rock), or when leveled up with a Moon Shard in the Bag (Pokémon XD).
Glaceon when leveled up near an Ice Rock (Generation IV onward).
We don't have Moss or Ice rocks, just Eevee candies. Is the evolution in Pokémon GO random, or is there a way to control which evolution is chosen?