Elite Trainer Mark on X: Onix was Brock's first ever Pokémon. However, it didn't even evolve under his ownership, it evolved into Steelix while his brother Forrest was taking care of it.

REQUEST] What would Steelix's anatomy have to look like to be metallic and still have as low of a mass/volume as it does? : r/theydidthemath

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I'm making a Pokemon Game where you fight the Gen 1 gym leaders backward but also changed thinking about reversing the Elite 4 order as well and giving them dual typing to

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Ash's Pikachu - Bulbapedia, the community-driven Pokémon encyclopedia