The Icy Rock, first appearing in Pokémon Diamond, Pearl, and Platinum games, is a hold item that extends the duration of the move Hail, which normally last for only five turns, so it lasts for eight turns instead. (A 60% increase in time).
 In-Game Descriptions
- Diamond/Pearl/Platinum: A Pokémon hold item that extends the duration of the move Hail used by the holder.
- HeartGold/SoulSilver: A Pokémon hold item that extends the duration of the move Hail used by the holder.
- Black/White: A Pokémon held item that extends the duration of the move Hail used by the holder.
 How To Obtain
• This item cannot be bought in shops in-game on any generations and game cartridges.
• This item can be traded between Diamond, Pearl, Platinum, HeartGold, SoulSilver, Black, and White games, provided the Pokémon being traded is holding the Icy Rock as its item and both game cartridges can trade back and forth.
- Diamond/Pearl/Platinum: The Icy Rock can be obtained from mining it in the Sinnoh Underground.
- HeartGold/SoulSilver: The Icy Rock can be found on the Icy Mountain Road Pokéwalker Route after taking 4,000 steps and using the Dowsing MCHN.
- Black/White: The Icy Rock can be obtained from the parasol lady on Route 8 once a day during the nighttime.
 Strategizing with the Icy Rock
A good strategy is to send an Ice-type Pokémon holding the Icy Rock into battle against an effective type matchup, such as Grass, and use Hail as your first move. Then, the opposing Pokémon will suffer damage each turn of the hailstorm, while you'll remain unscathed.
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