Tierra is a character who appeared in the episode "Control Freak!" She's an archaeologist on a mission to locate a hidden chamber supposedly containing a magical mask and staff with the ability to control Pokémon minds.
The group actually finds her unconscious at her dig site, thanks to Brock's Golbat leading them there. Once she recovers, Tierra brings them back to her office and shows them the ancient tablet that sparked her solo research project. Brock helps out by fixing her equipment and even upgrading her laptop so it can sync with Golbat's Supersonic waves. When her digging machine gets destroyed, he doesn't hesitate to use his Geodude to tunnel down to the underground temple.
The problem is Team Rocket gets there first with their Dig-a-Tron mecha. When Jessie finds the mask and picks up the staff, she becomes hostile and starts using its mind-control powers for herself. The resulting chaos reduces the underground temple to rubble as Team Rocket makes their escape, though somehow Tierra and the group manage to get out safely. After Pikachu blasts Team Rocket away, Tierra recovers both the mask and staff, which means she can finally continue her research.
Content compiled by AnimeList.moe from publicly available sources.
