Abstract: A gaming machine has a random percentage selection device for randomly selecting a percentage value of a jackpot amount. The gaming machine may have a plurality of random percentage selection devices for selecting a plurality of individual percentage values and a summation unit for summing the individual percentage values to provide a summed percentage value. A display means is provided for displaying the individual percentage values and the summed percentage value. The gaming machine is particularly used together with a plurality of primary slot machines. Each of the primary slot machines has a supplementary winning combination which entitles the player thereof to operate the gaming machine to try and win a part, or all of, the jackpot.

Abstract: The invention provides a card based game of chance which includes a set of standard playing cards; an additional special card; and a random selection device to be operated when the special card is dealt to a player to determine a supplementary payout to that player. Betting participation in a card based game of chance is enhanced by adding the special card to a standard set of cards and permitting a player to whom the card is dealt to operate a random selection device to determine a supplementary payout. Apparatus to play the game has a set of standard playing cards; a special card to be added to the set; and a random selection device to be operated when the special card is dealt to a player to determine a supplementary payout to that player.