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When the Poké Radar chain has reached 40, (as seen on Pokétch App 20#) the player can reset the chain and a patch of grass may sparkle. Once the player starts a battle in that patch of grass, the Pokémon will be Shiny. Entering the patch of shaking grass that is the farthest away from the previous patch of grass increases the chances of meeting the same kind of Pokémon consecutively. Long chains increase the chance of finding a Shiny Pokémon, which is indicated by the patch of grass glowing white twice rather than shaking. Though rare, it is possible to encounter a Shiny Pokémon in a regular shaking patch.
