US Patent 8388435 Gaming system having multiple wagering games with shared features

A method of playing a wagering game comprises receiving a wager, and generating a randomly selected first outcome of a first wagering game, the first outcome comprising a first plurality of symbols arranged in a first matrix. The method further comprises generating a randomly selected second outcome of a second wagering game, the second outcome comprising a second plurality of symbols arranged in a second matrix, and simultaneously displaying the first outcome and the second outcome on at least one display. The method further comprises detecting an occurrence of a triggering event, in response to the triggering event, copying a first special symbol occurring in the first outcome into the second outcome to yield a modified second outcome, and evaluating the first outcome and the modified second outcome for winning combinations of symbols.