It debuted in Showdown In Pewter City. How Brock obtained Geodude is unknown; however, Geodude has always been a vital member of Brock's team, always being there for battle or for certain contests. Geodude is an unfailingly fun-loving Pokémon that is known to have fun with Ash's Pikachu and the other Pokémon on many occasions, though it was seldom seen. When Brock left for Hoenn, he also left Geodude in his younger brother, Forrest's care.
When Brock returns to Pewter City in the episode, Grating Spaces!, Geodude along with Flint's Golem and both Brock's Steelix and Crobat to reunite with Brock. After Max reveals to them that Team Rocket's Meowth is stealing the Gym's Pokémon which Forrest recognizes it while it was lying that he hasn't stole anything. Forrest angrily releases Geodude to tackle Meowth on the ground revealing its motives of stealing. Brock was furious to see Team Rocket is responsible for remodelling the Gym where they pose as Gym remodellers calling them a disgrace while Forrest also became angered from their actions for stealing the Gym's Pokémon is was unforgivable challenging them to a fight. Geodude uses Sandstorm to keep them at bay while teaming up with Brock's Steelix by deflect both Aggron and Charizard's attacks which they are owned by Butch and Cassidy. Steelix hits Aggron with Iron Tail while Geodude hits Charizard's gut with Mega Punch. Team Rocket is soon blasted off by Ash's Pikachu and Donphan's Thunderbolt and Hyper Bean combination followed by Brock's Steelix's Dragon Breath and Geodude's Sandstorm. After the incident, Brock's family along with Brock's Pokémon waved goodbye to Ash and his group.