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The Trovita Gym (Japanese: ユズジム Yuzu Gym) is the official Gym of Trovita Island. The Gym Leader is Rudy. Trainers who defeat him receive the Spike Shell Badge.
The Trovita Gym made its only anime appearance in Misty Meets Her Match!. In this episode, Ash Ketchum challenged Rudy in a formal Gym battle.
Trovita Island is surrounded by large rocks that were formed millions of years ago when the island rose out of the ocean. The Spike Shell Badge reflects this unique island trait. Trovita Island is home to the third member of the Orange Crew, Rudy and his sister Mahri. The Trovita Gym battlefield is on a big flat rock.
There is also a two-story building that resembles a Pokémon Center. On the first floor is a gigantic dance floor/exercise room for Rudy's Pokémon. While the battlefield is located elsewhere, this building serves more as a training center.
Like all Gyms in the Orange Archipelago, the Trovita Gym executes a unique battling style. Before the Leader, Rudy, can be challenged, a qualifier must be completed in which the Trainer's Pokémon must knock down or destroy a succession of targets. The qualifier is carried out on a boat traveling down a river on Trovita Island, and the targets are shaped like bullseyes. Knocking down all the targets will entitle the challenger to battle with Rudy.
Because the battles of the Gym are conducted on the aforementioned rock, there is a risk that either Trainer's Pokémon may fall. In battle, both Trainers will use three Pokémon. Rudy's Pokémon will be of the same type as the challenger. Because of this, he has a wide variety of Pokémon at his disposal, all of which have been trained to dance. Rudy uses his Pokémon's unconventional skills to overcome the type disadvantage usually found when fighting a Pokémon of the same type, such as spinning out of the way of attacks.