Patent ID: 8360840

Claim:
A method of operating a gaming machine having a display and a game controller arranged to control images of symbols displayed on the display, the game controller being arranged to play a spinning reel game wherein at least one random event is caused to be displayed on the display and, if a predefined winning event occurs, the machine awards a prize, the method comprising: triggering a bonus feature, said bonus feature including a series of free spinning reel games, each of said free spinning reel games having associated reel strips carrying a number of symbols including a winnable symbol; before playing each of said free spinning reel games, inserting a said winnable symbol into one of the reel strips while not increasing said number of symbols on the other of said reel strips to increase the chance of a said winnable symbol being spun up in a said free spinning reel game, said inserting creating a stacked array of a plurality of said winnable symbols; and spinning said reel strips to provide a visible indication of said increase in the chance of a said winnable symbol being part of a winning event during a free spinning reel game.