Abstract: Games requiring thinking and strategy are provided with concealable cards or game pieces, physical or virtual, which can be played on a game board which may be a square or rectangular grid or other shape. Together the cards or game pieces are a collection of sets and there may be more spaces on the game board than there are cards or game pieces in the collection. The cards may be a subset of a regular deck of cards, such as five sets of four cards of the same value, each of different suits, wherein these 20 cards are to be played on a 5×5 game board so that there are 5 extra spaces that will be empty after all cards are played. Cards may be played one at a time or grouped and some may be concealed before being played, with the order of concealed and revealed varying. A player aims to place the cards or game pieces to form combinations such as four of a kind in value in either rows or columns to score points. Other combinations may be played for such as three of a kind, flushes, full houses etc.