Rummikub ("rummy-cube") is a tile-based game for two to four players, combining elements of the card game rummy and mahjong. Players have 14 or 16 tiles initially and take turns putting down tiles from their racks into sets (groups or runs) of at least three, drawing a tile if they cannot play.... An important feature of the game is that players can work with the tiles that have already been played. (wikipedia.org)