A slot machine and method of conducting a wagering game is disclosed. The slot machine incorporates a topper having a display unit corresponding to each primary game reel. Depending on its current state, the display units turn on and turn off in response to pre-established game indicia aligning along a payline. A payout is awarded when all the display units are turned on simultaneously after a game play. In other versions, a bonus display comprises a grid of display units or a segmented display unit in the form of a gaming symbol. With the grid, once a winning pattern of display units is illuminated, a bonus award is provided. Similarly, with the segmented display units, once all segments of one or more display units are illuminated, a bonus award is provided.