Bruno's Onix, International Pokédex Wiki

Pokemon 4095 Crystal Onix Pokedex: Evolution, Moves, Location, Stats

Onix Reverse - Pokémon Go Pokémon card 036/078

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

Pokemon Heartgold and Soulsilver In-Game Tier List (MkII)

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

Pokemon HeartGold Version Box Shot for DS - GameFAQs

Pokemon HeartGold Version - ds - Walkthrough and Guide - Page 8 - GameSpy

Every Available Pokemon Trade In HeartGold And SoulSilver (& Where To Find Them)

Pokemon HeartGold and SoulSilver :: The Johto Safari Zone

Onix (Pokémon) - Bulbapedia, the community-driven Pokémon encyclopedia