Abstract:
A slot machine allows the operation of two or more independent slot games at the same time. The two or more slot games may have the exact same game format or different game formats. Each slot game pays independently of the other slot game, but uses a common pool of credits. One player may play cooperatively with another player, or other players, at the same gaming machine; or one player may play two or more slot games at the same time on the same machine. By placing multiple slot games on the same machine, the amount of money deposited into the slot machine increases without taking up any additional casino floor space. Therefore, casinos, especially those with restricted floor space or limited quantities of slot machines, may generate higher profits per square foot and offer more games to their clientele.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    This application is related to and claims the benefit of U.S. Provisional Application Serial No. 60/228,471, filed Aug. 29, 2000, entitled “Method of Playing a Slot Machine (Dual Slots)”. 
     
    
     
       FIELD OF TECHNOLOGY  
         [0002]    This invention relates primarily to electronic video gaming devices, and more particularly to electronic video slot machines which can operate two or more slot games at the same time on the same gaming device.  
         BACKGROUND OF THE INVENTION  
         [0003]    In a conventional slot machine, a single game is offered to the player. To play the game, a player deposits money in the form of coins, gaming tokens or paper currency either into a coin head or bill acceptor (“the coin-in”). The coins and gaming tokens are collected in a reservoir inside the gaming machine (“the hopper”) while the paper currency is collected in the bill acceptor inside the gaming machine. If the coins, gaming tokens or paper currency are validated as authentic, the player accrues the appropriate number of playing units (“credits”) on a credit meter on the gaming machine depending on the denomination of the wager as set on the gaming machine. For example, a twenty-five cent gaming machine will accrue four credits for each dollar deposited into the gaming machine by way of the coin head or the bill acceptor.  
           [0004]    After accruing credits on the credit meter, the player determines how many credits he wishes to wager on the next spin of the slot reels (“total bet”) and then spins the reels by pressing the spin button or by pulling a handle. When the reels stop spinning, symbols are displayed on each of the slot reels. The player collects credits for predetermined winning symbol combinations that appear in specific locations (“pay lines”) on the slot reels. Winning combinations typically require that three or more of the same symbols appear adjacent to each other reading from the leftmost position of a pay line to the right.  
           [0005]    Credits are awarded to the player for each winning symbol combination based on a predetermined schedule (“pay table”). The number of credits indicated by the pay table is multiplied by the number of credits wagered on the winning pay line. For example, a player may wager two credits each on five pay lines, spin the reels, and collect twice the amount indicated on the pay table for a winning symbol combination appearing on a pay line.  
           [0006]    Following any pays, the credits won are added to the player&#39;s balance of credits shown in the credit meter. As long as the player has credits on the credit meter, the player may continue to play the gaming machine or the player may collect the remaining balance of credits by pressing a Cash Out button the gaming machine. In addition, the player may view the rules of the game by pressing the Help button before any spin.  
           [0007]    Every casino seeks to maximize revenues from its gaming devices. One criteria used by casinos is to measure the amount of the coin-in per square foot of casino floor space. Thus, a casino can increase its revenues by increasing the amount of coin-in per square foot. Based on the mathematical probabilities built into each gaming machine, the casino makes on average a percentage of each coin deposited in the machine: the more coin-in, the more revenue. The amount of coin-in, therefore, can be maximized in two main ways:  
           [0008]    First, increase the number of machines per square foot. With each generation of new slot machine, the machine carcass and footprint grows smaller. However, since the conventional slot machine is restricted by the size of the physical reels (“mechanical reels”), cathode ray tube (“video reels”), or liquid crystal displays (“LCD reels”), the reduction of the overall size and depth of the slot machine is limited.  
           [0009]    Second, increase the maximum total bet allowed on each spin. With each new slot machine game, the maximum bet which the player is allowed to make grows larger. Since the conventional slot player is not likely to wager his entire bankroll on a single spin of the reels, however, the maximum total bet per spin is limited.  
           [0010]    In addition to these two primary methods of increasing revenue, coin-in may also be enhanced by increasing the speed of play. For example, all other things being equal, a game on a slot machine which takes six seconds to play will result in more coin-in than a game on a slot machine which takes eight seconds to play.  
           [0011]    The speed of the play of each game becomes even more noticeable when the situation of one player operating two separate slot machines is considered. When a player wishes to play two slot machine games at the same time, the player must insert money into two coin slots or bill acceptors—one on each slot machine. The player must monitor the outcome of the spinning of the reels on two separate display screens—one on each slot machine. The player must also reach back and forth between the two slot machines to control the bet, spin and cash out buttons on each of the slot machines. Managing more than one machine to play multiple games at the same time, therefore, results in a much slower average speed of play. Furthermore, the physical effort involved in managing multiple machines decreases the player&#39;s overall enjoyment of playing the games.  
           [0012]    With the foregoing problems in mind, it is an object of the present invention to provide a slot machine which requires reduced installation space and which will generate a higher total wager to increase revenues per square foot of casino floor space, while at the same time increasing average speed of play and enhancing the player&#39;s enjoyment of playing multiple games at the same time.  
         SUMMARY OF THE INVENTION  
         [0013]    The present invention includes a variety of methods of play that can be programmed on an electronic video slot machine. Each electronic video slot machine is programmed to operate two or more slot games at the same time. In a preferred embodiment of the present invention, the machine displays two slot games on the same video display screen. Each of the slot games may be identical in every respect, including but not limited to the wagering options, the symbol sets used on the reels, the graphics of the screen design, the sounds used during the operation of the slot game and the bonus features. Alternatively, the method of the present invention may use different games, such as two different slot games with different symbol sets, graphics, sounds and bonus features; or two different types of games, such as two video poker games or even a slot game with a video poker game.  
           [0014]    Each slot game shares a common pool of credits. All wagers for each game are deducted from the common pool of credits and all awards earned from each game are accrued into the same common pool of credits and shown on the common credit meter (e.g., the winnings of one game may be used to pay for the wagers of the other game). In a preferred embodiment of the present invention, the machine contains only one common pool of credits. Alternatively, any number of common pools of credits may be used, such as two common pools of credits used by four players playing the machine in two-person teams.  
           [0015]    Each slot game plays independently of the other. A wager made on one slot game has no effect on the wager made on the other slot game; the play pattern or the play strategy employed by a player on one slot game has no effect on the play pattern or play strategy of the other slot game; and the outcome of one slot game does not affect the outcome of the other slot game. In a preferred embodiment of the present invention, the slot games are played independently as described above. Alternatively, the games may interact through common bonus features, such as a bonus game which may be activated by the outcomes achieved during the play of either slot game. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    [0016]FIG. 1 shows a perspective view of a gaming machine of the present invention.  
         [0017]    [0017]FIG. 2 shows a front view of the gaming machine of the present invention.  
         [0018]    [0018]FIG. 3 shows a front view of the screen display portion of the gaming machine of the present invention with a first representative game outcome.  
         [0019]    [0019]FIG. 4 shows a front view of the screen display portion of the gaming machine of the present invention with a second representative game outcome.  
         [0020]    [0020]FIG. 5 shows a front view of the screen display portion of the gaming machine of the present invention with a third representative game outcome.  
         [0021]    [0021]FIG. 6 shows a front view of the screen display portion of the gaming machine of the present invention with a fourth representative game outcome. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]    The preferred embodiment of present invention includes the play of base games and additional bonus features, including Wild symbols and Scatter pays.  
         [0023]    Base Games. To play the base games, the player establishes a common pool of credits, plays one or more base games by choosing which games to play, selecting pay lines, setting the wager per pay line, spinning the reels, and collecting credits for winning symbol combinations and bonus features.  
         [0024]    Gaming Apparatus. In a preferred embodiment of the present invention, two slot games are displayed side by side on the single video display in the gaming machine. However, any other orientation of the slot games could be used, such as one of the slot game being displayed above the other slot game on the same video display device. In addition, two or more slot games may be displayed simultaneously on one or more video displays.  
         [0025]    [0025]FIGS. 1 and 2 show a representative gaming machine  10  that is configured to practice the present invention. The gaming machine  10  includes a video screen display  20  in any suitable location such as in the general center area of the gaming machine  10 . Belly glass  48  and top glass  49  can be provided upon which can be printed or otherwise marked information about the game. The gaming machine  10  also includes a button panel  50  which provides the mounting area for a plurality of buttons used by the player to operate the gaming machine. The button panel  50  also can provide space for a coin head  80  into which the player deposits coins or gaming tokens to make a wager or to accrued credits on a credit meter. A bill acceptor  82  is also provided in any suitable location into which the player can insert paper currency or coupons which are also used to make wagers or to accrued credits on the credit meter. A coin tray  84  is also provided as is conventional into which coins are dispensed from a coin hopper (not shown) when a player wishes to cash out.  
         [0026]    On the interior of the gaming machine  10  are the computer controls that operate the gaming machine as well as the other conventional hardware used in a gaming machine such as the coin hopper, the video monitor hardware, the wiring harness, the coin validator, the bill acceptor equipment and other suitable devices used to make the gaming machine  10  operational.  
         [0027]    The layout of the gaming machine  10  shown in FIGS. 1 and 2 is only representative of one suitable layout and other layouts may be used as desired.  
         [0028]    Video Display. In a preferred embodiment of the present invention, each of the slot games would have a five reel display using a five column by three row matrix. Alternatively, the games could utilize any number of columns and reels, such as a 3 column by 3 row matrix. As shown in FIGS. 1 and 2, the left slot game  22  and the right slot game  24  are positioned side by side, although any other suitable orientation may be used.  
         [0029]    Buttons. In the preferred embodiment of the present invention, a set of buttons are mounted on the button panel and are used by the player to control the functions of each slot game—the left slot game  22  and the right slot game  24 . As shown in FIG. 2, these buttons include Select Pay Lines  24 L and  24 R, Bet Per Line  26 L and  26 R, Max Bet  28 L and  28 R, Spin Reels  30 L and  306 R, Pay Table  24 L and  24 R, and Help  32 L and  32 R. Each button may be further identified on the top of each button with “LEFT” and “RIGHT” titles, such as Spin LEFT Reels and Spin RIGHT Reels. Any or all of these control buttons may be displayed on the video display and/or buttons hard wired to the gaming device. If necessary, any number of buttons may added to further facilitate control of the games  
         [0030]    The preferred embodiment of the present invention can also use a set of control buttons to operate both games at the same time, such as Spin BOTH Reels button  40  that spins the reels of both slot games and Cash Out button  42  that issues the number of credits displayed on the Credits meter  60  in coin, or other currency, to the player.  
         [0031]    Meters. In the preferred embodiment of the present invention, a set of meters are shown on the video display screen  20  to display the salient information for each of the left game  22  and the right game  24 , including Number of Pay Lines  52 L and  52 R, Amount Bet Per Line  54 L and  54 R, Total Bet  56 L and  56 R, and Paid  56 L and  56 R. The Number of Pay Lines meter  52 L and  52 R is associated with the Select Pay Lines button  24 L and  24 R and displays the current number of Pay Lines Selected. The Amount Bet Per Line meter  54 L and  54 R is associated with the Bet Per Line button  26 L and  26 R and displays the number of credits wagered per pay line. The Total Bet, meter  56 L and  56 R displays the cumulative value of the Number of Pay Lines  52 L and  52 R and Amount Bet Per Line  54 L and  54 R; and the Paid meter  56 L and  56 R displays the number of credits won on the last spin. In addition, the games both share the Credits meter  60  which displays the total number credits remaining in the common credit pool.  
         [0032]    Credit Pool. In a preferred embodiment of the present invention, the player deposits coins, tokens or paper currency into the coin head slot  80  or a paper currency bill acceptor  82  to establish a common pool of credits. The amount of this common pool of credits is displayed to the player on the Credits meter  60 . The common pool of credits increases and decreases according to the player&#39;s wins or losses and may be supplemented, if necessary, by the player by additional deposits of coins, tokens or paper currency.  
         [0033]    Choose Games. In a preferred embodiment of the present invention, a single player may choose to play up to two base games at the same time on the same gaming machine. Alternatively, two players may share the machine with one player operating each game. Alternatively, the player may play one slot game and allow the other slot game to remain inactive.  
         [0034]    Select Pay Lines. In a preferred embodiment of the present invention, each of the slot games have a plurality of pay lines upon which to wager. The pay lines wagered on by the player would be activated a predetermined order. For example, the slot game may utilize nine pay lines of which the player&#39;s first wager is applied to pay line  1 , the second wager is applied to pay line  2 , the third wager is applied to pay line  3 , and so on up until the ninth wager is applied to pay line  9 . However, the games may utilize any other order of pay line activation and fewer or greater than nine pay lines may be used.  
         [0035]    Bet Per Line. In a preferred embodiment of the present invention, the player sets the value of the wager on each pay line; the same amount is wagered on each pay line. Alternatively, the player could be allowed to make wagers of different amounts on each pay line. The total amount wagered is determined by summing the amounts wagered on each pay line.  
         [0036]    Spin Reels. In a preferred embodiment of the present invention, the player then causes the slot machine to operate by effecting a “spin” of the reels. This can be done in any suitable manner, such as the player pressing a “spin” button on the machine&#39;s button panel and watching a video simulation of a reel slot machine.  
         [0037]    Symbol Set. In a preferred embodiment of the present invention, each symbol is chosen from a set of twelve symbols. For each spin, the machine randomly displays three symbols from the symbol set on each reel. A common theme can be used for the symbols, and in one embodiment, the symbols are related to a fishing theme. However, any suitable symbols may be used, including the traditional fruit symbols that commonly appear on other slot machines. Furthermore, fewer or greater that twelve symbols may be used as a symbol set.  
         [0038]    Winning Symbol Combinations. In a preferred embodiment of the present invention, the player is paid for predetermined winning combinations of symbols that appear on an active pay line. Each winning combination may involve three or more of the same symbols that appear adjacent to each other reading from the leftmost position of a pay line to the right. Each winning combination pays the amount indicated on the game&#39;s pay table times the amount wagered on that pay line. Furthermore, any appropriate pay table may be used and each slot game may use its own pay table. Alternatively, any desired group of symbols may be designated as winning symbol combinations and fewer or greater than three symbols could be designated as winning symbol combinations.  
         [0039]    Base Games Example. Sam Slotsky is standing in front of a nickel-denomination version of the preferred embodiment of the present invention. Sam sees two sets of 5-reel slot games side-by-side on the video display; the game  22  on the left is IGT&#39;s TEXAS OIL™ slot game and the game  24  on the right is IGT&#39;s LITTLE GREEN MEN™ slot game. Any suitable slot games may be used and the slot games may both be the same slot game or may be different slot games as in this example.  
         [0040]    Below each game on the button panel  50  are seven buttons: Select Pay Lines  24 L and  24 R, Bet Per Line  26 L and  26 R, Bet Max  28 L and  28 R, Spin Reels  30 L and  30 R, Pay Table  34 L and  34 R, Help  32 L and  32 R and Cash Out  36 L and  36 R. In addition, there are also four meters on the video screen display  20  below each game: Number of Pay Lines  52 L and  52 R, Amount Bet Per Line  54 L and  54 R, Total Bet  56 L and  56 R and Paid  58 L and  58 R. Between the games, in the bottom-center of the video display  20 , are two touch screen button locations and one meter: Spin Both Reels touch screen button location  66 , Cash Out touch screen button location  62 , and Credits meter  60 .  
         [0041]    Sam presses the Pay Table  34 L button for the left game  22  to view the pays for winning combinations achieved on the left game  22 . Using the numbers  1  to  12  to represent the symbol set, with  10  as the Wild symbol and  11  and  12  as the scatter symbols. The pay table for symbols  1  to  9  reads as follows (refer to the Bonus Features section below for more details on Wild symbols and Scatter Symbols):  
                                                           9-9-9-9-9 10000   9-9-9-9.. 2000   9-9-9 ....400           8-8-8-8-8 7500   8-8-8-8.. 1500   8-8-8 ....300           7-7-7-7-7 5000   7-7-7-7.. 1000   7-7-7 ....200           6-6-6-6-6 2500   6-6-6-6.. 500   6-6-6 ....100           5-5-5-5-5 1500   5-5-5-5.. 300   5-5-5 ....60           4-4-4-4-4 750   4-4-4-4.. 150   4-4-4 ....30           3-3-3-3-3 500   3-3-3-3.. 100   3-3-3 ....20           2-2-2-2-2 250   2-2-2-2.. 50   2-2-2 ....10           1-1-1-1-1 100   1-1-1-1.. 20   1-1-1 ....4           5 Scatters   1000X Total Bet           4 Scatters   100X Total Bet           3 Scatters   10X Total Bet                      
 
         [0042]    Sam then presses the Help button  32 L to view the rules of the TEXAS OIL™ left slot game  22 . After reading the game rules for the left game  22 , he returns to the base games screen.  
         [0043]    Sam presses the Pay Table button  34 R for the right game  24  to view the game&#39;s pays for winning combinations on the right game  24 . Using the numbers  1  to  12  to represent the symbol set, with  10  as the Wild symbol and  11  and  12  as the scatter symbols. The pay table for symbols  1  to  9  reads as follows (refer to the Bonus Features section below for more details on Wild symbols and Scatter Symbols):  
                                                           9-9-9-9-9 25000   9-9-9-9 ..6000   9-9-9 .. 1500           8-8-8-8-8 12000   8-8-8-8.. 3200   8-8-8 ....800           7-7-7-7-7 6500   7-7-7-7.. 1600   7-7-7 ....400           6-6-6-6-6 3200   6-6-6-6.. 800   6-6-6 ....200           5-5-5-5-5 1600   5-5-5-5.. 400   5-5-5 ....100           4-4-4-4-4 1000   4-4-4-4.. 240   4-4-4 ....60           3-3-3-3-3 500   3-3-3-3.. 120   3-3-3 ....30           2-2-2-2-2 250   2-2-2-2.. 60   2-2-2 ....15           1-1-1-1-1 100   1-1-1-1.. 20   1-1-1 ....5           5 Scatters   15 Free Spins           4 Scatters   9 Free Spins           3 Scatters   5 Free Spins                      
 
         [0044]    Sam then presses the Help button  32 R to view the rules of the LITTLE GREEN MEN™ right game  24 . After reading the rules for the right game  24 , he returns to the base games screen.  
         [0045]    Sam deposits $20 into the bill receptor and the Credits meter counts up from 0 to 400 since the denomination for this game is five cents per credit. Sam then his chooses the wager on the left game  22 :  
         [0046]    The left game&#39;s Number of Pay Lines meter  52 L reads  1 . Sam presses the Select Pay Lines button  24 L four times and the Number of Pay Lines meter  52 L counts up from 1 to 5. As Sam presses the Select Pay Lines button  24 L, the video display shows the locations of each selected pay line on the 5 column by 3 row matrix. For example, the first pay line starts in the middle row of the first column and proceeds in the straight line through the middle row of columns 2 through 5;  
         [0047]    The left game&#39;s Amount Bet Per Line meter  54 L reads  1 . Sam presses the Bet Per Line button  26 L two times and the Amount Bet Per Line meter  54 L counts up from 1 to 3;  
         [0048]    The Total Bet meter  56 L started at 1, but after Sam&#39;s adjustments it now reads  15 ; and  
         [0049]    The Paid meter  58 L reads  0 .  
         [0050]    Sam&#39;s adjustments to the left game  22  have not affected the right game  24  at all. So, Sam uses the control buttons under the right game  24  to select his wager for the right game  24 :  
         [0051]    The Number of Pay Lines meter  52 R at 9;  
         [0052]    The Amount Bet Per Line meter  54 R at 2;  
         [0053]    The Total Bet meter  56 R at 18; and  
         [0054]    The Paid meter  58 R reads  0 .  
         [0055]    After setting his wagers, Sam presses the Spin Reels button  30 L under the left game  22 . The Credits meter  60  counts down from 400 to 385. The reels of the left game  22  spin and then come to a stop. Using the numbers  1  to  12  to represent the symbol set, with  10  as the Wild symbol and  11  and  12  as the scatter symbols, the reels of the left game  22  display the following symbols as shown in FIG. 3:  
         [0056]    [0056] 3   1   6   7   5   
         [0057]    [0057] 4   4   4   3   8  (Winning symbol combination in bold.)  
         [0058]    [0058] 6   6   1   9   7   
         [0059]    The left game  22  awards Sam ninety credits for a winning symbol combination of  4 - 4 - 4  on pay line  1 . The award reflects the left game  22  pay table which states that  4 - 4 - 4  pays thirty credits for each credit wagered upon the pay line; or thirty credits times three credits wagered by Sam on pay line  1 . The Credits meter  60  counts up from 385 to 475 and the left game Paid meter  58 L reads  90 .  
         [0060]    Sam then presses the Spin Reels button  30 R under the right game  24 . The Credits meter  60  counts down from 475 to 457. The reels of the right game  24  spin and then come to a stop. Using the numbers  1  to  12  to represent the symbol set, with  10  as the Wild symbol and  11  and  12  as the scatter symbols, the reels of the right game  24  display the following symbols as shown in FIG. 3:  
                                                   4   1   2   7   5       5   4   1   3   8       6   6   4   9   7                  
 
         [0061]    The right game awards Sam 120 credits for a winning symbol combination of  4 - 4 - 4  on pay line  4 . The award reflects the right game  24  pay table which states that  4 - 4 - 4  pays sixty credits for each credit wagered upon the pay line; or sixty credits times two credits wagered by Sam on pay line  1 . The Credits meter  60  counts up from 457 to 577 and the right game&#39;s Paid meter  58 R reads  120 .  
         [0062]    Again, Sam presses the Spin Reels button  30 R under the right game. The Credits meter  60  counts down from 577 to 562. The reels of the right game  24  spin and, before the reels stop, Sam presses the Spin Reels button  30 L under the left game  22 . The Credits meter  60  counts down from 562 to 544. When the reels of the right game  24  stop, there are no winning symbol combinations and the right game Paid meter  58 R reads  0 . And when the reels of the left game  22  stop, there are two winning combinations which pay a combined 150 credits. The Credits meter  60  counts up from 562 to 712 and the left game Paid meter  58 L reads  150 .  
         [0063]    Sam continues to play the slot games by pressing the Spin Both button  40 . The Credits meter  60  counts down from 712 to 679. The reels of the right game  24  and the left game  22  spin and come to a stop as shown in FIG. 4. Using the numbers  1  to  12  to represent the symbol set, with  10  as the Wild symbol and  11  and  12  as the scatter symbols, the reels of the left game  22  display the following symbols:  
                                                   2   2   2   2   2       5   4   1   4   9       7   1   3   9   7                  
 
         [0064]    And the reels of the right game  24  display the following symbols:  
                                                   2   1   5   8   3       5   4   6   4   4       3   2   3   6   2                  
 
         [0065]    The left game  22  awards Sam 750 credits for a winning symbol combination of  2 - 2 - 2 - 2 - 2  on pay line  2 . The award reflects the right game&#39;s pay table which states that  2 - 2 - 2 - 2 - 2  pays two hundred fifty credits for each credit wagered upon the pay line; or two hundred fifty credits times three credits wagered by Sam on pay line  2 . The Credits meter  60  counts up from 679 to 1,429 and the left game Paid meter  58 L reads  750 . The right game  24  did not produce a winning symbol combination and the right game Paid meter  58 R reads  0 .  
         [0066]    Content with his winnings, Sam presses the Cash Out button  42 . The gaming device issues 1,429 nickels or any other form of currency, including cash, an EZ-PAY™ ticket, or electronic payment.  
         [0067]    Bonus Features. During play of the base games, the player may receive special pays for bonus features, such as Wild Symbols and Scatter pays.  
         [0068]    Wild Symbols. Wild symbols replace any or all other symbols in determining winning outcomes. Alternatively, wild symbols may only replace limited subsets of the other symbols. Wild symbols, therefore, increase the possibility of a player achieving winning combinations and the pay table must reflect that the wild symbols are in use. In a preferred embodiment of the present invention, the wild symbol acts as its own symbol (e.g., three wild symbols on a pay line) while at the same time a wild symbol could also replaces every other symbol. Alternatively, any suitable replacement rules for wild symbols could be used.  
         [0069]    Each wild symbol may also be used to affect payouts which utilize one or more wild symbols. For example, a wild symbol used in a winning combination of symbols, may double the value of the winning combination. The slot game can also be configured so that the wild symbols increase or decrease the value of any payout in any manner which results in an average value that can be utilized to control the gaming machine&#39;s overall average payouts. In the preferred embodiment of the present invention, however, the Wild symbols do not affect the value of the winning symbol combinations.  
         [0070]    Scatter Pays. A scatter pay awards the player a predetermined payout for the appearance of a scatter symbol, or a combination of scatter symbols, anywhere on the main game screen display. This is known in the art as a “Scatter Pay” in that the scatter symbols may appear anywhere on an active pay line (i.e. a pay line upon which the player has made a wager), across multiple active pay lines, or even on a position upon which the player did not make a wager. Scatter pays award a specific number of credits and/or trigger a bonus feature, such as entertaining animations, free spins, enhanced pay table values, and/or selection of bonus objects.  
         [0071]    In a preferred embodiment of the present invention, a scatter symbol combination of three or more scatter symbols award: a specific number of credits with an entertaining animation bonus feature; a selection of bonus objects and/or free spins. The number of credits awarded may be determined by multiplying the total amount wagered by a random number within a predetermined range of numbers; or the number of free spins awarded may be set by the number of scatter symbols displayed on the reels. Alternatively, the value of the bonus feature could be determined by any other suitable calculation as long as the bonus feature results in an average value that can be utilized to control the overall average payouts of the slot game.  
         [0072]    Wild symbols and Scatter pays do not necessarily result in the award of credits. The activation of the bonus feature may only result in a payout some percentage of the time. For example, Wild symbols may appear on the screen without forming a winning symbol combination. Scatter symbols may require the presence of another element, such as another special symbol. Alternatively, a bonus feature which pays more or less frequently could be used as long as the bonus feature results in an average value that can be utilized to control the overall average payouts of the slot game. In the preferred embodiment of present invention, Wild symbols do not always result in winning symbol combinations, however, Scatter pays always result in the award of credits.  
         [0073]    Bonus Feature Example.  
         [0074]    Sam Slotsky returns to the same nickel-denomination version of the preferred embodiment of the present invention, as described above in the Base Games Example section. Sam deposits $20 into the bill acceptor and the Credits meter  60  counts up from 0 to 400. Sam then presses the Help buttons  32 L and  32 R to view the rules of the games:  
         [0075]    The rules of the left game  22  state that there are two bonus features: Wild symbols and Scatter pays. Wild symbols replace any symbol on the reels except for a Scatter symbol. Scatter pays of ten to one thousand times the Total Bet occur whenever three or more Scatter symbols appear anywhere on the slot reels.  
         [0076]    The rules of the right game  24  state that there are two bonus features: Wild symbols and Scatter pays. Wild symbols replace any symbol on the reels except for a Scatter symbol. Scatter pays of three to fifteen free games occur whenever three or more Scatter symbols appear anywhere on a pay line upon which the player wagered.  
         [0077]    After reading the rules, Sam returns to the base games screen. Using the control buttons, Sam adjusts his wagers on the left game  22  and the right game  24 . For the left game  22 , he sets the Number of Pay Lines  52 L at 5 and the Amount Bet Per Line  54 L at 3; and, for the right game  24 , he sets the Number of Pay Lines  52 R at 9 and the Amount Bet Per Line  54 R at 2.  
         [0078]    After setting his wagers, Sam presses the Spin Reels button  30 L under the left game  22 . The Credits meter  60  counts down from 400 to 385. The reels of the left game  22  spin and then come to a stop. Using the numbers  1  to  12  to represent the symbol set, with  10  as the Wild symbol and  11  and  12  as the scatter symbols, the reels of the left game  22  display the following symbols as shown in FIG. 5:  
                                                   11   1   6   7   5       4   10   4   3   8       6   6   2   11   7                  
 
         [0079]    The left game  22  awards Sam 290 credits for two winning symbol combinations of  4 - 10 - 4  on pay line  1  and  6 - 10 - 6  on pay line  5 . The  10  symbol is Wild and acts as a  4  symbol to make the  4 - 4 - 4  combination and then acts as a  6  symbol to make the  6 - 6 - 6  combination. The  10  symbol does not replace as a Scatter symbols and, therefore, does not act as an  11  symbol.  
         [0080]    The 290 credit award reflects the left game&#39;s pay table which states that  4 - 4 - 4  pays thirty credits for each credit wagered upon the pay line (e.g., thirty credits times three credits wagered by Sam on pay line  1 ) and also states that  6 - 6 - 6  pays one hundred credits for each credit wagered upon the pay line (e.g., one hundred credits times two credits wagered by Sam on pay line  5 ). The Credits meter  60  counts up from 385 to 675 and the left game Paid meter  58 L reads 290.  
         [0081]    Again, Sam presses the Spin Reels button  30 L under the left game  22 . The Credits meter  60  counts down from 675 to 660. The reels of the left game  22  spin and then come to a stop. Using the numbers  1  to  12  to represent the symbol set, with  10  as the Wild symbol and  11  and  12  as the scatter symbols, the reels of the left game display the following symbols as shown in FIG. 6:  
                                                   11   1   6   7   5       4   11   4   3   8       6   6   2   11   7                  
 
         [0082]    The left game  22  displays an entertaining animation of oil pumping from an oil well and awards Sam one hundred fifty credits for a Scatter symbol combination of three  11  symbols anywhere on the slot reels. The award reflects the left game pay table which states that three Scatter Symbols pay ten times the Total Bet. The Credits meter  60  counts up from 660 to 810 and the left game Paid meter  58 L reads 150.  
         [0083]    Sam then presses the Spin Reels button  30 R under the right game  24 . The Credits meter  60  counts down from 810 to 792. The reels of the right game  24  spin and then come to a stop. Using the numbers  1  to  12  to represent the symbol set, with  10  as the Wild symbol and  11  and  12  as the scatter symbols, the reels of the left game display the following symbols as shown in FIG. 6:  
                                                   12   12   12   12   5       4   5   4   3   8       6   6   2   4   7                  
 
         [0084]    The right game  24  awards Sam nine free spins for a Scatter symbol combination of four  12  symbols adjacent from left to right on pay line  3 . The award reflects the right game pay table which states that four Scatter Symbols result in nine free spins. The game proceeds to spin nine times at the same wager level; Sam wins a total of 425 credits. The Credits meter  60  counts up from 792 to 1,217 and the right game Paid meter  58 R reads 425.  
         [0085]    Content with his winnings, Sam presses the Cash Out button  42 . The gaming device issues 1,217 nickels or any other form of currency, including cash, an EZ-PAY™ ticket, or electronic payment.  
         [0086]    The present invention is not constrained to parameters listed above. The number of games operated by the machine at the same time is not critical; more than two games can be used. The number of pay lines used in each game is also not critical; more or less than five pay lines can be used. The number of symbols located on each pay line may be more or less than the three symbol locations described above. However, it is preferable to have at least three symbol locations to provide mathematical combinations in sufficient amounts to offer reasonable winning payouts. Also the number of symbols with the symbol set used in a slot game may vary. However, it is preferable to have at least seven symbols within the symbol set to provide mathematical combinations in sufficient amounts to offer reasonable winning payouts.  
         [0087]    In addition, the present invention may be modified to work on multiple video displays or sets of mechanical slot reels with a base game on each display or set of reels. Existing slot machines with multiple games use multiple reel mechanisms that are dependent and, therefore, do not allow for separate operation. The present invention, however, uses video displays and allows each base game to operate independently using separate controls, pay tables, wagers, symbols sets, base game rules, bonus features and animations. Furthermore, the base games may be played one-at-a-time, in an alternating fashion, or simultaneously.  
         [0088]    Given the flexibility of the present invention, therefore, the preferred embodiment listed above should be considered illustrative and not limiting. Various modifications and additions may be made and will be apparent to those skilled in the art. Accordingly, the invention should not be limited by the foregoing description, but rather should be defined by the following claims.