How to get Crystal Onix & Crystal Steelix in PBF

IV] Shiny Onix, Rock Tunnel, HeartGold, 10678 REs, Phase 2 for shiny Kangaskhan : r/ShinyPokemon

I want onix! #pokemon #nintendoswitch #fyp #151 #nintendo #pokemonscar

Pokemon Naranja #16 - Catch Crystal Onix (part 1)

Got back to this game, now at Frost Mountain. PS: The Shiny Geodude (now a graveler, as you can see) was completely random and I was not expecting it. : r/PokemonUnbound

Onyx Gijinka by munchii3 on DeviantArt

I can't seem to catch this Onix, no matter what pokeball I throw at it. I have 3 badges (can catch Pokémon up to level 35) Help?? : r/pokemonshield

PokéPlay: Pokémon Y - Part 15 - The Great Onix Disaster of '13

Pokémon Platinum- Usando só Pokémon do tipo Lutador - Parte 1 (Crédito

BBC iPlayer - Pokémon: XY - Series 17 - XY: 24. Climbing the Walls!

Gen 3] - Taking the Pick my Team challenge