After a winning spin at some Microgaming slot machines you will have the option to gamble your winnings. If you don't choose to gamble, you will be paid out your winnings. If you decide to gamble you will have the chance to double or even quadruple your winnings. If you choose to the double option you will select one of two cards, one of which is the same suit as your card. If you choose to try to quadruple your winnings you will select one of four cards. One of these four cards will be the same suit as your card, giving you a one in four chance of winning. This is similar to doubling in video poker.