Their value will be determined by the total number of entrants into the tournament. Only one prize will be awarded per player. The cards are issued one per occasion from a random deck. Winners not present must leave an address in order to recieve their awards. For Double Elimination, use a standard double elimination tree.
Players play until they have two losses.
For Round Robin, use any round robin match setup where everyone plays everyone else. The winner is the player with the most victories, second is second most, and third is third most. For Ongoing Challenge, set a period of time that the tournament will take place. Players can sign up at any time during the tournament. Each entry gets you one character with 3 lives.