it's really complicated. hope you get the card with the highest value (value from lowest to highest is toad, yoshi, daisy, peach, luigi, mario) if you win, your coins will add up to the opponent's card value minus your card's current value. if you lose, it will be your card value minus the opponent's card value. you can also bet. if you win while having a large bet, it will be what i said before times whatever the bet number is. okay if you actually read all of this, you know how to play.
Inspired from luigi's casino from super mario 64 ds and new super mario bros.