Bruno's Onix - Bulbapedia, the community-driven Pokémon encyclopedia

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Pokémon Adventures: HeartGold and SoulSilver, Vol. 2, Book by Hidenori Kusaka, Satoshi Yamamoto, Official Publisher Page

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Best Monotype Runs in Pokemon Gold, Silver, Crystal, HG, and SS

Geodude or Onix? - Pokémon HeartGold/SoulSilver - Giant Bomb

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Why is Onix, a 28 ft ROCK Pokemon, half the weight of a 6 foot Snorlax?

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Onix Characters - Giant Bomb