a cabinet;

a display device mounted to the cabinet and including a graphical user interface (GUI) display screen displaying computer-generated images thereon;

a control unit operably coupled to the display device, the control unit including a random number generator, a memory device storing computer-executable instructions, and a processor programmed to execute the computer-executable instructions to perform an algorithm to display an animated sequence of computer-generated images on the display device GUI including the steps of:

generating a plurality of virtual reels by:

accessing a reel strip data file stored in the memory device including computer-executable instructions associated with each virtual reel including a plurality of reel strips including a plurality of fixed symbol positions and at least one reel strip including a variable symbol position;

accessing a variable symbol reel strip data file stored in the memory device including computer-executable instructions associated with the variable symbol position including a plurality of special wheel symbols and associated selection weights;

randomly selecting a special wheel symbol from the plurality of special wheel symbols using the random number generator;

populating each fixed symbol position with a corresponding game symbol; and

populating the variable symbol position with the randomly selected special wheel symbol;

displaying a game screen on the display device GUI including the plurality of virtual reels displaying a plurality of game symbols, a bonus wheel positioned above the plurality of virtual reels and including a plurality of wheel wedges displaying prize symbols and a prize selector, and a bonus wheel meter displayed above the virtual reels and including a number of bonus wheel symbols;

animating the virtual reels to simulate spinning and stopping the virtual reels to display an instance of the game including a bonus wheel symbol and a bonus wheel upgrade symbol appearing in the virtual reels with the virtual reels stopped;

animating a copy of the bonus wheel symbol to move from the virtual reels to appear on the bonus wheel meter to increase the number of bonus wheel symbols displayed in the bonus wheel meter;

accessing a bonus wheel data file including computer-executable instructions associated with each wheel wedge including a wheel wedge ID and an associated selection weight;

randomly selecting a wheel wedge displayed on the bonus wheel based on the associated selection weights using the random number generator;

modifying the bonus wheel by transforming a corresponding prize symbol displayed with the randomly selected wheel wedge to display an upgraded prize symbol;

animating a copy of the bonus wheel upgrade symbol to move from the virtual reels to appear on the bonus wheel meter; and

animating the bonus wheel to spin and stop upon determining the increased number of bonus wheel symbols included in the bonus wheel meter is equal to a predefined number of bonus wheel symbols.