From Bulbapedia, the community-driven Pokémon encyclopedia.
Joshua (Japanese: シンタロー Shintarō) is one of the three Club Members from the Water Club, under Club Master Amy, in Pokémon Trading Card Game.
This person is required to duel with in order to reach their Club Master.
Joshua challenges to a 4-card prize match.
Upon defeat, he awards the player with two Mystery booster packs.
Michael plays two different decks over the course of the game. Both decks are four prize card matches.
Conserving Water Deck
Conserving Water Deck (Japanese: のこされたみずのデッキ) is the first deck played by Joshua. Upon defeat, Joshua rewards the player with two Beginning Pokémon booster packs.
This battle is available from the beginning of the game in the side communications room. Joshua continues using this deck after GR-3 is defeated, and does so until sometime after the player has access to GR Island. Later in the game, his deck is upgraded and this decklist can no longer be battled.
Energy Removal Deck
Energy Removal Deck (Japanese: エネルギー・リムーブデッキ) is the second deck played by Joshua. Upon defeat, Joshua rewards the player with two Sky Flying Pokémon booster packs.
Joshua starts playing this deck at some point later in the game, after the player has access to GR Island. Once available to play against, this is the only deck that Joshua uses.