When used in a Catching Show encounter in Pal Park, it catches the encountered Pokémon without fail.
The player does not gain ownership of the caught Pokémon until they complete the Catching Show and choose to place the caught Pokémon in their Storage System. The migrated Pokémon remain in the Poké Balls in which they were contained in Generation III; no Pokémon can have a Park Ball as its own Poké Ball.
When the player participates in Pal Park's Catching Show, they receive six Park Balls exclusively for use within the show. They are not placed in the player's Bag, and the player returns any unused Park Balls they have any remaining if they leave the Catching Show.