Hidden Grottos, also referred as Hidden Hollows in Japan, are small areas throughout the Unova Region. These areas are accessible by going through small gaps in between trees. Essentially this is what determines a Hidden Grotto's location. This area contains a variety of possible items or Pokémon. All such areas render Pokémon with their Hidden Ability. Apart from regular items you may find there are also hidden items that can be collected in Hidden Grotos. Make sure to use your Dowsing MCHN, while in a Hidden Grotto. Once you have farmed a Hidden Grotto, there is a 5% chance of it being regenerated for every 256 steps taken.
Hidden Grottos were introduced with the launch of the Pokémon Games, Pokémon Black 2 and Pokémon White 2. Unlike the previous Generation V Games, this feature allows access to some Pokémon with their Hidden Ablity, without the use of an internet connection.
All Hidden Grottos have the chance to obtain these items:
Poke Ball, Great Ball, Ultra Ball, Repel, Super Repel, Potion, Super Potion, Hyper Potion, Full Heal
All Hidden Grottos have the chance to obtain these hidden items:
Growth Mulch, Damp Mulch, Stable Mulch, Gooey Mulch, Big Mushroom, TinyMushroom, Red Shard, Blue Shard, Yellow Shard, Green Shard, Rare Candy, PP Up, PP Max
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