Gaming machine and method with symbol collection and array expansion

A method of operating a gaming machine, the gaming machine primarily dedicated to playing at least one casino wagering game, the gaming machine including an electronic display device and one or more electronic input devices, the electronic display device configured to display an active array of symbol positions, the method comprising the operations of:

• detecting, by game-logic circuitry associated with the gaming machine and via at least one of the one or more electronic input devices, a physical item associated with a monetary value that establishes a credit balance;
• initiating, by the game-logic circuitry, the casino wagering game in response to an input indicative of a wager drawn from the credit balance;
• spinning and stopping symbol-bearing reels through one or more spins to place special value-bearing symbols borne by the stopped reels in the active array and collecting the values borne by the special value-bearing symbols that appear in the active array over the one or more spins in a first collection;
• in response to a first predetermined number of the special value-bearing symbols appearing in the active array over the one or more spins, expanding, by the game-logic circuitry via the electronic display device, the active array to include additional symbol positions, repeating the spinning and stopping operations with the expanded active array for one or more additional spins, wherein none of the special value-bearing symbols that appear in the active array are carried over to the expanded active array, and collecting the values borne by the special value-bearing symbols that appear in the expanded active array over the one or more additional spins in a second collection;
• providing, by the game-logic-circuitry, an award based on the special value-bearing symbols, wherein the provided award is based on at least the first collection in response to the first predetermined number of the special value-bearing symbols not appearing in the active array over the one or more spins, wherein the provided award is based on at least the second collection in response to the first predetermined number of the special value-bearing symbols appearing in the active array over the one or more spins and a second predetermined number of the special value-bearing symbols not appearing in the expanded active array over the one or more additional spins;
• and
• receiving, by the game-logic-circuitry via at least one of the one or more electronic input devices, a cashout input that initiates a payout from the credit balance.