Danny.

Danny (Japanese: ダン Dan) is the Gym Leader of the Navel Island Gym. He hands out the Sea Ruby Badge to trainers who defeat him. His Japanese seiyu is 松本保典 Tamoten Matsumoto, and his English voice actor is Dan Green.

He is the second Gym Leader Ash encounters in the Orange Archipelago. He appears to be is in his mid-20s and enjoys water sports including sailing and windsurfing. He and Misty seem to develop a relationship in the anime episode Navel Maneuvers.

Danny doesn't simply battle Ash, however; instead, he challenges Ash to work with his Pokémon in order to win the Badge. Initially, Danny and Ash have to climb a mountain without the aid of any of their Pokémon. Then Ash and Danny each choose three Pokémon to build a bobsled (or toboggan) of sorts, and the final challenge is a bobsled race down the side of the mountain.