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Hidden Grotto (Japanese: 隠し穴Hidden Hollow) is a feature introduced in Pokémon Black 2 and White 2 that allows the player to catch Pokémon that have a Hidden Ability or find items. The contents of the Hidden Grottoes are random, and if they are empty, for each 256 steps, they have a 5% chance to regenerate, usually with different content than what was inside on the previous visit. Hidden Grottoes will not regenerate unless the items are obtained or the Pokémon are captured or defeated.