How do you get the dubious disc?

To get Dubious Disc, the player must defeat one of the following Pokémon trainers in Battle Café Singles format:

- Celosia (1780 Coins or More)

- Chantelle (3736-6760 Coins)

- Ilima (8960-12800 Coins)

- Lana (4592-8360 Coins)

- Sophocles (3136-5760 Coins)