In Pokémon GO, the PokéStops that Team GO Rocket invaded have a different appearance than regular PokéStops in the Map View. Keep an eye out for any stops that twitch and look discolored. As you get closer to an Invaded PokéStop, you will see the Team GO Rocket logo appear over it. When you approach an Invaded PokéStop, you can engage in a Team GO Rocket Battle to defend the PokéStop. Winning Team GO Rocket Battles gives you a chance to catch Shadow Pokémon.
After catching a Shadow Pokémon, you can choose to Purify the Pokémon with a combination of Stardust and Candy. Purifying a Shadow Pokémon will make it stronger and reduce the amount of Stardust and Candy required to Power Up, Evolve, or learn a new attack. The Charged Attack, Frustration, will be replaced with the exclusive Charged Attack called Return, and the Pokémon’s aura will also change from a dark aura to a bright, luminous aura. The required amount of items needed for Purification has been reduced. Rattata and Zubat now require 1,000 Stardust and one Candy; Bulbasaur, Charmander and Squirtle now require 3,000 Stardust and three Candy; Dratini and Snorlax now require 5,000 Stardust and five Candy.
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