A gaming machine for displaying a computer-animated reel game is described herein. The gaming machine includes one or more processors programmed to execute an algorithm to display an animated sequence of computer-generated images of the computer-animated reel game on a display device GUI including the steps of initiating a prize upgrade animation sequence by randomly selecting a number of cells displaying prize symbols based on the number of collected prize upgrade symbols included in a prize upgrade symbol meter, determining a type of prize symbol being displayed in each selected cell, accessing a prize upgrade data lookup table to determine an upgrade prize symbol associated with each type of prize symbol being displayed in each selected cell, and sequentially animating each associated upgrade prize symbol to replace a corresponding prize symbol displayed in each selected cell.