Patent attributes
A symbol frame mechanic for a gaming device is described. The symbol frame mechanic generates a random based game outcome in a game instance of a base game that triggers a supplemental game feature. The random based game outcome includes a plurality of target feature symbols. The symbol frame mechanic generates a plurality of feature symbol frames at symbol window positions with the target feature symbols. The target feature symbols trigger generation of the feature symbol frames. The symbol frame mechanic determines a current symbol frame state according to the feature symbol frames and generate a random based game outcome in a game instance of the supplemental game feature. The symbol frame mechanic updates the current symbol frame state based on combining the random based game outcome in the game instance of the supplemental game feature with the current symbol frame state.