Learning Rummy 51: A Complete Guide Rummy 51 is an engaging card game that blends strategy, skill, and a little bit of luck. A standaonline cash rummy gamesrd deck of cards is used for play, & two to six players are usually involved. Forming legitimate melds—card combinations that can be either sets (three or four cards of the same rank) or runs (three or more consecutive cards of the same suit)—is the aim of the game.