A gaming system randomly selects a trigger value for a feature, which starts when the current value of a symbol counter reaches the trigger value. In some examples, a gaming system includes memory that stores data defining reel strips. When a symbol counter is initialized, an initial value of the symbol counter is randomly selected from a range of allowable initial values having an upper limit. A trigger value is randomly selected from a range between the initial value and a ceiling value, which is greater than the upper limit. For each of one or more instances, symbols are selected from the reel strips for display, and the current value of the symbol counter is incremented based on the count of designated symbols, if any, among the selected symbols. Responsive to the current value of the symbol counter reaching the trigger value, the feature is started.