Gaming machine with symbol propagation

1. A computer-implemented method comprising:

selecting, by one or more processors of a gaming machine, a set of symbols associated with an outcome event of a reel-based game, wherein the reel-based game is executed on behalf of a client machine, wherein selecting the set of symbols involves spinning a plurality of reels to determine the outcome event, and wherein a memory stores respective pluralities of symbols for the reels;

storing, by the one or more processors, the set of symbols in the memory;

determining, by the one or more processors, that the set of symbols includes a predetermined symbol on a designated reel and does not include any winning combination;

in response to determining that the set of symbols includes the predetermined symbol on the designated reel and does not include any winning combination, replacing, by the one or more processors, one or more symbols in the set of symbols with predetermined symbols such that the symbol set after replacement includes a winning combination; and

storing, by the one or more processors, the set of symbols after replacement in the memory.

2. The method of claim 1 , wherein the predetermined symbol is a Wild symbol.

3. The method of claim 1 , wherein each reel comprises a respective cyclical sequence of symbols, and wherein selecting the set of symbols comprises:

for each reel, randomly selecting a respective reel position that displays a subsequence of the symbols on the reel that are part of the set of symbols.

4. The method of claim 1 , wherein selecting the set of symbols comprises:

simulating a spin of all reels, resulting in the set of symbols.

5. The method of claim 1 , wherein selecting the set of symbols comprises:

transmitting, to the client machine, a representation of the set of symbols, wherein reception of the set of symbols causes the client machine to display a spin of the plurality of reels resulting in the set of symbols.

6. The method of claim 1 , wherein replacing the one or more symbols in the set of symbols with predetermined symbols comprises:

transmitting, to the client machine, a representation of the set of symbols after replacement, wherein reception of the set of symbols after replacement causes the client machine to display a spin of the plurality of reels resulting in the set of symbols after replacement.

7. The method of claim 1 , wherein replacing the one or more symbols in the set of symbols with predetermined symbols comprises:

causing the client machine to display an animation in which the predetermined symbols that replace the one or more symbols move from an arrangement position of the predetermined symbol in the designated reel to their respective arrangement positions.

8. The method of claim 1 , wherein the reel-based game has five reels and each of the five reels displays three symbols at a time.

9. The method of claim 1 , wherein the operations further comprise:

determining a payout amount associated with the symbol set after replacement; and

transmitting, to the client machine, an indication of the payout amount.

10. The method of claim 9 , wherein the payout amount is based on the predetermined symbol in the designated reel and at least one of the predetermined symbols that replace the one or more symbols.

11. The method of claim 9 , wherein the client machine is associated with a credit account, and wherein the credit account is debited to play the reel-based game and credited by the payout amount.

12. The method of claim 1 , wherein the gaming machine simultaneously executes reel-based games in real time on behalf of at least 30 client machines, and wherein each of the at least 30 client machines communicates with the gaming machine by way of a wide-area packet-switched network.

13. The method of claim 1 , wherein at least one of the predetermined symbols that replace the one or more symbols does not contribute to the winning combination.

14. The method of claim 1 , wherein the designated reel is a middle reel of the plurality of reels.

15. An article of manufacture including a non-transitory computer-readable medium, having stored thereon program instructions that, upon execution by a gaming machine, cause the gaming machine to perform operations comprising:

selecting a set of symbols associated with an outcome event of a reel-based game, wherein the reel-based game is executed on behalf of a client machine, wherein selecting the set of symbols involves spinning a plurality of reels to determine the outcome event, and wherein a memory of the gaming machine stores respective pluralities of symbols for the reels;

storing the set of symbols in a memory;

determining that the set of symbols includes a predetermined symbol on a designated reel and does not include any winning combination;

in response to determining that the set of symbols includes the predetermined symbol on the designated reel and does not include any winning combination, replacing one or more symbols in the set of symbols with predetermined symbols such that the symbol set after replacement includes a winning combination; and

storing the set of symbols after replacement in the memory.

16. The article of manufacture of claim 15 , wherein selecting the set of symbols comprises:

simulating a spin of all reels, resulting in the set of symbols.

17. The article of manufacture of claim 15 , wherein selecting the set of symbols comprises:

transmitting, to the client machine, a representation of the set of symbols, wherein reception of the set of symbols causes the client machine to display a spin of the plurality of reels resulting in the set of symbols.

18. The article of manufacture of claim 15 , wherein replacing the one or more symbols in the set of symbols with predetermined symbols comprises:

transmitting, to the client machine, a representation of the set of symbols after replacement, wherein reception of the set of symbols after replacement causes the client machine to display a spin of the plurality of reels resulting in the set of symbols after replacement.

19. The article of manufacture of claim 15 , wherein replacing the one or more symbols in the set of symbols with predetermined symbols comprises:

causing the client machine to display an animation in which the predetermined symbols that replace the one or more symbols move from an arrangement position of the predetermined symbol in the designated reel to their respective arrangement positions.

20. A gaming system configured for symbol replacement in a reel-based game, wherein the reel-based game is executed on behalf of a client machine, wherein the reel-based game involves spinning a plurality of reels to determine outcome events, the gaming system comprising:

a plurality of gaming devices each including at least one display device and a plurality of input devices including (i) an acceptor of a physical item associated with a monetary value, (ii) a validator configured to identify the physical item, and (iii) a cash-out button actuatable to cause an initiation of a payout associated with a credit account;

one or more gaming device processors; and

one or more gaming device memory devices storing (i) respective pluralities of symbols for the reels and (ii) a plurality of gaming device instructions executable by the one or more gaming device processors to perform operations comprising:

selecting a set of symbols associated with an outcome event of the reel-based game, wherein selecting the set of symbols involves spinning the plurality of reels to determine the outcome event;

storing the set of symbols in the one or more gaming device memory devices;

determining that the set of symbols includes a predetermined symbol on a designated reel and does not include any winning combination;

in response to determining that the set of symbols includes the predetermined symbol on the designated reel and does not include any winning combination, replacing one or more symbols in the set of symbols with predetermined symbols such that the symbol set after replacement includes a winning combination; and

storing the set of symbols after replacement in the one or more gaming device memory devices.