From Bulbapedia, the community-driven Pokémon encyclopedia.
Senta is a member of Team Great Rocket from Template:Card GB 2. He's one of the Trainers at the GR Water Fort.
His deck, Paralyzed! Paralyzed! Deck (Japanese: マヒ！マヒ！デッキ), focuses on Pokémon. He will not duel against the player unless they use a deck with 4 Magikarp cards.
When defeated, he gives out one Psychic Battle booster pack. Also, when defeated for the first time, he frees the imprisoned Grand Master Jack and puts a bridge over the water to make it possible to go to the next room, allowing the player to reach Aira.