There are three playable mini-games in Beyond Good and Evil.
Location: Akuda Bar, ground floor
Goal: each player starts with 4 pallets. Shoot all of the pallets from your side to your opponent's side. The game is over when all 8 pallets are on your opponent's side.
Prize: Bet 100 or 1000 units to win 200 units or a Pearl, respectively.
Location: Akuda Bar, second floor
Goal: keep a careful eye on the shell under which Peepers puts the ball as he moves them around. Choose the correct shell when he's done to win the game.
Prize: Bet 50, 100 or 200 units to win 100, 200 or 400 units, respectively.
Location: Mdisk Decoder Menu
Acquisition: given to you by the Mammago brothers once you have collected all of the Pearls in the game.
Goal: using both analogue sticks, keep control of two pearls that move through an ever changing obstacle course. At the end of each level, the level repeats again but with the balls moving faster, making the obstacles harder to dodge.
Prize: high score counter and advanced ranking in the Darkroom.