Patent Abstract:
A system and method for conducting a wagering game providing an opportunity to earn an increased award is disclosed. A randomly selected outcome from a plurality of possible outcomes is displayed. The plurality of possible outcomes each including a plurality of symbols arranged in an array. An additional symbol is displayed separate from the array. If the displayed randomly selected outcome includes a winning symbol combination resulting in a first award, a determination is made whether the displayed additional symbol can be combined with the winning symbol combination to yield a second award being larger than the first award. The first award is provided if the additional symbol cannot be combined with the winning symbol combination to yield the second award. The larger second award is provided if the additional symbol can be combined with the winning symbol combination to yield the second award.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. national stage of International Application No. PCT/US2007/023257, filed Nov. 5, 2007, which is related to and claims the benefit of U.S. Provisional Application No. 60/858,298, filed Nov. 9, 2006, each of which is hereby incorporated by reference herein in its entirety. 
    
    
     COPYRIGHT 
     A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever. 
     FIELD OF THE INVENTION 
     The present invention relates generally to gaming machines, and methods for playing wagering games, and more particularly, to a wagering game including a supplemental symbol adapted to extend winning symbol combinations. 
     BACKGROUND OF THE INVENTION 
     Gaming machines, such as slot machines, video poker machines and the like, have been a cornerstone of the gaming industry for several years. Generally, the popularity of such machines with players is dependent on the likelihood (or perceived likelihood) of winning money at the machine and the intrinsic entertainment value of the machine relative to other available gaming options. Where the available gaming options include a number of competing machines and the expectation of winning at each machine is roughly the same (or believed to be the same), players are likely to be attracted to the most entertaining and exciting machines. 
     Shrewd operators consequently strive to employ the most entertaining and exciting machines, features, and enhancements available because such machines attract frequent play and hence increase profitability to the operator. Therefore, there is a continuing need for gaming machine manufacturers to continuously develop new games and improved gaming enhancements that will attract frequent play through enhanced entertainment value to the player. 
     Another way to increase the entertainment value of a game is to enhance the display of the gaming machines. For gaming machines with video displays, improvements in video technology have enabled the display of richer and more colorful graphics. For gaming machines with mechanical displays, however, the enhancements early on were less technologically advanced. For example, some mechanical reel symbols were colored by backlighting the mechanical symbols with colored lighting elements. Sometimes the reel itself might contain electroluminescent elements that defined one or more reel symbols. To display a symbol in multiple colors or formats using such an arrangement, multiple electroluminescent elements were needed for the symbol. 
     Recent advances in transmissive display technology have made it possible to more easily modify the appearance of mechanical displays. A transmissive display is essentially a transparent video display that is superimposed over the mechanical display. The transmissive display may then be operated to display selected video images over the mechanical display. These video images may include translucent portions such that the underlying mechanical display is visible, but in an altered state (i.e., different color, texture, etc.). The video images may also include opaque portions so as to completely block out parts of the underlying mechanical display. 
     The above-described transmissive display technology gives wagering game designers the capability and flexibility to more easily design and modify the appearance of mechanical displays. Accordingly, there is a need to develop new and improved wagering games for mechanical displays using this technology, with features that take full advantage of the capabilities of the transmissive display to thereby enhance the entertainment value of the wagering games. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, a method of conducting a wagering game providing an opportunity to earn an increased award is disclosed. The method comprises displaying a randomly selected outcome from a plurality of possible outcomes. The plurality of possible outcomes each including a plurality of symbols arranged in an array. The method further comprising displaying an additional symbol separate from the array. If the displayed randomly selected outcome includes a winning symbol combination resulting in a first award, the method also includes determining whether the displayed additional symbol can be combined with the winning symbol combination to yield a second award being larger than the first award. The first award is provided if the additional symbol cannot be combined with the winning symbol combination to yield the second award. The larger second award is provided if the additional symbol can be combined with the winning symbol combination to yield the second award. 
     According to another aspect of the present invention, a method of conducting a wagering game allowing an opportunity to form an enhanced winning symbol combination comprises receiving a primary wager from the player for playing the wagering game. The method further comprises initiating the wagering game and displaying, via a plurality of reels having symbols thereon, a randomly selected outcome for the wagering game. The method also includes displaying a supplemental symbol in addition to the randomly selected outcome. The supplemental symbol being initially displayed separately from the plurality of reels. In response to the randomly selected outcome forming a winning symbol combination and the supplemental symbol matching the winning symbol combination, the method additionally includes combining the supplemental symbol in conjunction with the winning symbol combination to form an enhanced winning symbol combination. 
     According to yet another aspect of the present invention, a gaming system for playing a wagering game comprises a wager input device for receiving a primary wager to play a game of the wagering game. The gaming system further comprises a display for displaying a randomly selected outcome of the game and a supplemental symbol. The randomly selected outcome is indicated by a plurality of symbols arranged in an array and the supplemental symbol is unassociated with the array. A first award is provided in response to the randomly selected outcome forming a winning symbol combination. A second award is provided if the supplemental symbol matches the winning symbol combination. The second award is greater than the first award. 
     Additional aspects of the invention will be apparent to those of ordinary skill in the art in view of the detailed description of various embodiments, which is made with reference to the drawings, a brief description of which is provided below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a free standing gaming machine embodying the present invention. 
         FIGS. 2   a - 2   b  are cross-sectional side views of a display area embodying the present invention. 
         FIG. 3  is block diagram of a control system suitable for operating the gaming machine of  FIG. 1 . 
         FIG. 4  is a screen view of a game incorporating the present invention capable of being displayed on the gaming machine of  FIG. 1 . 
         FIG. 5  is a screen view of the reels of the game of  FIG. 4  after a play of the game. 
         FIG. 6  is another screen view of the reels of the game of  FIG. 4  after the play of the game. 
         FIG. 7  is a screen view of the reels of the game of  FIG. 4  after another play of the game. 
         FIG. 8  is a screen view of an alternate embodiment of the game incorporating the present invention capable of being displayed on the gaming machine of  FIG. 1 . 
     
    
    
     While this invention is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. 
     DETAILED DESCRIPTION 
     While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail various embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated. 
     Referring to  FIG. 1 , a mechanical reel gaming machine  10  similar to those used in gaming establishments, such as casinos, is shown. The gaming machine  10  comprises a housing  12  and a number of input devices, including a value input device  18  and a player input device  24 . For outputs, the gaming machine  10  comprises a primary display area  14  for displaying information about base wagering games and a secondary display area  16  for displaying game events, game outcomes, and/or signage information. The primary display area  14  and/or secondary display area  16  may also display information about bonus wagering games and progressive wagering games. In accordance with embodiments of the invention, the primary display area  14  comprises a plurality of mechanical reels  54  and a transmissive display  56  superimposed over the mechanical reels  54 . Each of the foregoing components is described in more detail below. While the exemplary embodiments described below refer to the mechanical reels  54 , in other embodiments the mechanical reels  54  can be replaced with video reels  54 ′ (see  FIG. 3 ). Thus, alternatively, the primary display area  14  can include the transmissive display  56  being superimposed over a plurality of video reels  54 . 
     The value input device  18  may be provided in many forms, individually or in combination, and is preferably located on the front of the housing  12 . The value input device  18  receives currency and/or credits that are inserted by a player. The value input device  18  may include a coin acceptor  20  for receiving coin currency. Alternatively, or in addition, the value input device  18  may include a bill acceptor  22  for receiving paper currency. Furthermore, the value input device  18  may include a ticket reader, or barcode scanner, for reading information stored on a credit ticket, a card, or other tangible portable credit storage device. The credit ticket or card may also authorize access to a central account, which can transfer money to the gaming machine  10 . 
     The player input device  24  comprises a plurality of push buttons  26  on a button panel for operating the gaming machine  10 . In addition, or alternatively, the player input device  24  may comprise a touch screen  28  mounted by adhesive, tape, or the like on the primary display area  14  (over the transmissive display  56 ) and/or on secondary display area  16 . The touch screen  28  contains soft touch keys  30  denoted by graphics on the underlying primary display area  14  and used to operate the gaming machine  10 . The touch screen  28  provides players with an alternative method of input. A player enables a desired function either by touching the touch screen  28  at an appropriate touch key  30  or by pressing an appropriate push button  26  on the button panel. The touch keys  30  may be used to implement the same functions as push buttons  26 . Alternatively, the push buttons  26  may provide inputs for one aspect of the operating the game, while the touch keys  30  may allow for input needed for another aspect of the game. 
     A player begins play of the base wagering game by making a wager via the value input device  18  of the gaming machine  10 . A player can select play by using the player input device  24 , via the buttons  26  or the touch screen keys  30 . The base game consists of a plurality of symbols arranged in an array, and includes at least one payline  32  that indicates one or more outcomes of the base game. Such outcomes are randomly selected in response to the wagering input by the player. At least one of the plurality of randomly-selected outcomes may be a start-bonus outcome, which can include any variations of symbols or symbol combinations triggering a bonus game. 
     In some embodiments, the gaming machine  10  may also include a player information reader  52  that allows for identification of a player by reading a card with information indicating his or her true identity. The player information reader  52  is shown in  FIG. 1  as a card reader, but may take on many forms including a ticket reader, bar code scanner, RFID transceiver or computer readable storage medium interface. Currently, identification is generally used by casinos for rewarding certain players with complimentary services or special offers. For example, a player may be enrolled in the gaming establishment&#39;s loyalty club and may be awarded certain complimentary services as that player collects points in his or her player-tracking account. The player inserts his or her card into the player information reader  52 , which allows the casino&#39;s computers to register that player&#39;s wagering at the gaming machine  10 . The gaming machine  10  may use the secondary display area  16  or other dedicated player-tracking display for providing the player with information about his or her account or other player-specific information. Also, in some embodiments, the information reader  52  may be used to restore game assets that the player achieved and saved during a previous game session. 
     In the illustrated embodiment, the gaming machine  10  is an “upright” version in which the primary display area  14  is oriented vertically relative to the player. Alternatively, the gaming machine may be a “slant-top” version in which the primary display area  14  is slanted at about a thirty-degree angle toward the player of the gaming machine  10 . Furthermore, although only three mechanical reels are shown in the primary display area  14 , those having ordinary skill in the art will recognize that the gaming machine  10  may comprise fewer or more mechanical reels (e.g., four reels, five reels, etc.), depending on the particular configuration of the primary display area  14 . 
       FIGS. 2   a - 2   b  illustrate exemplary implementations of the primary display area  14  in which a video image is superimposed over the mechanical reels  54 . Although not expressly labeled, each reel of the mechanical reels  54  has a plurality of reel symbols (see  FIG. 1 ) that represent a randomly-selected outcome of the wagering game. The video image may then be positioned over the mechanical reels  54  to enhance and/or alter the appearance (e.g., color, texture, etc.) of the mechanical reels  54 . There are at least two possible configurations for the primary display area  14 : a direct image configuration ( FIG. 2   a ), and a virtual image configuration ( FIG. 2   b ). These configurations are described below. 
     Referring to  FIG. 2   a , in the direct image configuration, a transmissive display  56  is positioned directly in front of the mechanical reels  54  and generates a direct image. In such an arrangement, the transmissive display  56  may be a flat panel transmissive video display, for example, a transmissive liquid crystal display (LCD) commercially available from LG Phillips LCD Co., Ltd., of Seoul, Korea, Sharp Electronics Corp. of Tokyo, Japan, and other display manufacturers. The flat panel transmissive video display is preferably preconfigured with the touch screen  28  (see  FIG. 1 ) mounted to a front surface of the display. 
     In the virtual image configuration, shown in  FIG. 2   b , a reflected video image is used instead of a direct image. In such an arrangement, the reflected video image may be generated by, for example, a standard video display  58  and a partially reflective mirror  60 . The standard video display  58  may be mounted below the mechanical reels  54  and substantially normal thereto, and the partially reflective mirror  60  may be positioned over the mechanical reels  54  at a predetermined angle (e.g., 45 degrees). Video images from the standard video display  58  are then reflected off the partially reflective mirror  60  so that they appear to a player to be superimposed over the mechanical reels  54 . The video projection display  58  may be any suitable video projection display known to those having ordinary skill in the art, including a CRT, LCD, dot matrix, LED, electro luminescent, and the like. In some embodiments, the primary display area  14  further comprises a transparent glass cover/window  62  positioned over the partially reflective mirror  60  to protect the mirror  60 . Such a cover/window  62  may be optionally configured with the touch screen  28  for receiving player input. 
     The superimposed video images may be selectively made transparent, semi-transparent (i.e., translucent), or opaque in selected places. This allows preselected images to be displayed over certain portions of the primary display area  14 , with the result that certain areas of the primary display area  14  are either altered in some way (e.g., highlighted, colored, etc.), or completely blocked by the superimposed images. All video images superimposed on the primary display area  14  may be rendered in two-dimensional (e.g., using Flash Macromedia™) or three-dimensional graphics (e.g., using Renderware™). The images may be played back (e.g., from a recording stored on the gaming machine  10 ), streamed (e.g., from the gaming network), or received as a TV signal (e.g., either broadcast or via cable). The images may be animated, or they may be real-life images, either prerecorded (e.g., in the case of marketing/promotional material) or as live footage, and the format of the video images may be an analog format, a standard digital format, or a high-definition (HD) digital format. Using superimposed video images in this way allows numerous types of improvements and enhancements to be made to the appearance of the primary display area  14  in real time and during on-going game play. 
     For information regarding the use of video overlay technology in gaming machines and for embodiments employing video overlay displays, the reader is referred to commonly assigned U.S. Published Application No. 20040198485, titled “Gaming Machine with Superimposed Display Image,” filed on Nov. 7, 2003, and also to commonly-assigned U.S. Pat. No. 6,517,433, titled “Reel Spinning slot Machine With Superimposed Video Image,” issued on Feb. 11, 2003, each of which being incorporated herein by reference in its entirety. 
     Turning now to  FIG. 3 , the various components of the gaming machine  10  are controlled by a central processing unit (CPU)  34 , also referred to herein as a controller or processor (such as a microcontroller or microprocessor). To provide gaming functions, the controller  34  executes one or more game programs stored in a computer readable storage medium, in the form of memory  36 . The controller  34  performs the random selection (using a random number generator (RNG)) of an outcome from the plurality of possible outcomes of the wagering game. Alternatively, the random event may be determined at a remote controller. The remote controller may use either an RNG or pooling scheme for its central determination of a game outcome. It should be appreciated that the controller  34  may include one or more microprocessors, including but not limited to a master processor, a slave processor, and a secondary or parallel processor. 
     The controller  34  is also coupled to the system memory  36  and a money/credit detector  38 . The system memory  36  may comprise a volatile memory (e.g., a random-access memory (RAM)) and a non-volatile memory (e.g., an EEPROM). The system memory  36  may include multiple RAM and multiple program memories. The money/credit detector  38  signals the processor that money and/or credits have been input via the value input device  18 . Preferably, these components are located within the housing  12  of the gaming machine  10 , but may be located outboard of the housing  12  and connected to the remainder of the components of the gaming machine  10  via a variety of different wired or wireless connection methods. 
     As seen in  FIG. 3 , the controller  34  is also connected to, and controls, the primary display area  14 , the player input device  24 , and a payoff mechanism  40 . The primary display area  14  in this embodiment uses the transmissive display  56  to superimpose a video image over the mechanical/video reels  54 / 54 ′, but a reflected image arrangement (see  FIG. 2   b ) may also be used in other embodiments. The payoff mechanism  40  is operable in response to instructions from the controller  34  to award a payoff to the player in response to certain winning outcomes that might occur in the base game or the bonus game(s). The payoff may be provided in the form of points, bills, tickets, coupons, cards, and the like. For example, in  FIG. 1 , the payoff mechanism  40  includes both a ticket printer  42  and a coin outlet  44 . However, any of a variety of payoff mechanisms  40  well known in the art may be implemented, including cards, coins, tickets, smartcards, cash, and the like. The payoff amounts distributed by the payoff mechanism  40  are determined by one or more pay tables stored in the system memory  36 . 
     Communications between the controller  34  and both the peripheral components of the gaming machine  10  and external systems  50  occur through input/output (I/O) circuits  46 ,  48 . More specifically, the controller  34  controls and receives inputs from the peripheral components of the gaming machine  10  through the input/output circuits  46 . Further, the controller  34  communicates with the external systems  50  via the I/O circuits  48  and a communication path (e.g., serial, parallel, IR, RC, 10bT, etc.). The external systems  50  may include a gaming network, other gaming machines, a gaming server, communications hardware, or a variety of other interfaced systems or components. Although the I/O circuits  46 ,  48  may be shown as a single block, it should be appreciated that each of the I/O circuits  46 ,  48  may include a number of different types of I/O circuits. 
     Controller  34 , as used herein, comprises any combination of hardware, software, and/or firmware that may be disposed or resident inside and/or outside of the gaming machine  10  that may communicate with and/or control the transfer of data between the gaming machine  10  and a bus, another computer, processor, or device and/or a service and/or a network. The controller  34  may comprise one or more controllers or processors. In  FIG. 3 , the controller  34  in the gaming machine  10  is depicted as comprising a CPU, but the controller  34  may alternatively comprise a CPU in combination with other components, such as the I/O circuits  46 ,  48  and the system memory  36 . The controller  34  may reside partially or entirely inside or outside of the machine  10 . 
     By virtue of the superimposed video images, a variety of traditional as well as visually-enhanced wagering games involving the mechanical reels  54  may be played on the gaming machine  10 . These wagering games may be provided to the gaming machine  10  using any suitable means known to those having ordinary skill in the art, including hardware upgrades as well as direct downloads via external systems  50 . In the latter case, the gaming machine  10  may communicate with the external systems  50  (in a wired or wireless manner) such that each machine operates as a “thin client,” having relatively less functionality, a “thick client,” having relatively more functionality, or through any range of functionality therebetween (e.g., a “rich client”). As a generally “thin client,” the gaming machine may operate primarily as a display device to display the results of gaming outcomes processed externally, for example, on a server as part of the external systems  50 . In this “thin client” configuration, the server executes game code and determines game outcomes (e.g., with a random number generator), while the controller  34  on board the gaming machine processes display information to be displayed on the display(s) of the machine. In an alternative “rich client” configuration, the server determines game outcomes, while the controller  34  on board the gaming machine executes game code and processes display information to be displayed on the display(s) of the machines. Numerous alternative configurations are possible such that the aforementioned and other functions may be performed onboard or external to the gaming machine  10  as may be necessary for particular applications. 
     Thus far, embodiments of the invention have only been described as video images being superimposed on the primary display area  14 . It is also possible, however, to superimpose the video images on the secondary display area  16  as well without departing from the scope of the invention. Still, in most embodiments, the primary display area  14  is the one with the video images superimposed thereon. The reason for this is because in most gaming machines  10 , the primary display area  14  is the one that includes the mechanical reels (e.g., for a slot machine), a mechanical wheel (e.g., a roulette game), one or more dice, a pachinko board, or other board game. In alternative embodiments, however, the primary display area  14  may include video reels  54 ′ by using a video display such as a CRT or LCD. Video images may then be superimposed on the video reels  54 ′ as needed. In further alternative embodiments, the primary display area  14  may include a diorama presenting a three-dimensional model of a game environment. The diorama may be stationary in some implementations, or it may slide or move around in one or more dimensions. 
     Turning now to  FIG. 4 , an image of a main game screen  63  is illustrated, according to one embodiment of the present invention. A player begins play of a basic wagering game by inserting a wager into the value input device  18  of the gaming machine  10 . A player can select play by using the player input device  24 , via the buttons  26  or the touch screen keys  30 . The CPU  34  (or a wagering-game control network in alternative embodiments) operates to execute a wagering game program causing the primary display area  14  to display the wagering game that includes a plurality of visual elements. 
     The main game screen  63  may be displayed on the primary display area  14  or on a portion thereof. In some embodiments, portions of the main game screen  63  may be displayed by superimposing a video image over mechanical reels (e.g., mechanical reels  54 ) or video reels (e.g., video reels  54 ′), as will be described in further detail below. In the illustrated embodiment, the main game screen  63  is used to display a plurality of reels  64   a - e  with symbols displayed thereon. The reels  64   a - e  are positioned such that the symbols are displayed relative to at least one payline  32  ( FIG. 1   a ), yielding a plurality of outcomes for the basic game. The main game screen  63  also includes a supplemental single-symbol reel  65  that will be described in more detail below. 
     The main game screen  63  may also display a plurality of game session meters and various buttons selectable by a player. The game session meters include a “credit” meter  66  for displaying a number of credits available for play on the machine; a “total line bet” meter  70  for displaying a number of credits wagered for the number of paylines played; a “total bet” meter  72  for displaying a total number of credits wagered for the particular round of wagering; and a “win” meter  74  for displaying an amount to be awarded based on the results of the particular round of wagering. The user-selectable buttons include a “pay” button  76  to collect the credits remaining in the credits meter  66 ; a “help” button  78  for viewing instructions on how to play the wagering game; a “pay table” button  80  for viewing a pay table associated with the basic wagering game; a “select lines” button  82  for changing the number of paylines (displayed in the lines meter  68 ) a player wishes to play; a “bet per line” button  84  for changing the amount of the wager which is displayed in the line bet meter  70 ; and a “spin” button  86  for moving the reels  64   a - e  and the reel  65 . While the gaming machine  10  allows for these types of player inputs, the present invention does not require them and can be used on gaming terminals having more, less, or different player inputs. 
     In  FIG. 4 , the five depicted reels  64   a - e  have a plurality of symbols displayed thereon that are in association with a number of paylines (e.g., payline  91  in  FIG. 5 ). Although the paylines themselves are not shown in  FIG. 4 , each payline may, for example, pass through a single symbol on each reel  64   a - e  as generally shown in  FIG. 1  and as illustrated with payline  91  in  FIG. 5 . The leftmost ends of the various paylines are denoted by end markers  90 , which may be color-coded to help distinguish the paylines from each other. The plurality of symbols displayed on the reels  64   a - e  is used to indicate a plurality of possible outcomes along each of the activated paylines. The depicted symbols generally correspond to a “TREASURE DIVER” theme and include: “NECKLACE” symbols  92 ; “RING” symbols  94 ; “CUP” symbols  96 ; “TREASURE BOX” symbols  98 ; “SHIELD” symbols  100 ; “BONUS” symbols  102 ; “TREASURE DIVER” symbols  104 ; “VASE” symbols  106 ; and “PLATE” symbols  108 . Other TREASURE DIVER-themed symbols may also be depicted. In other embodiments of the present invention, the gaming machine  10  may portray other themes with corresponding like-themed symbols. Further, standard gaming symbols such as “1-BAR” symbols, “2-BAR” symbols, “3-BAR” symbols, “CHERRY” symbols, “SEVEN” symbols, and “BELL” symbols may be depicted on the reels  64   a - e  in other embodiments. The reels  64   a - e  displaying these symbols may be either traditional mechanical reels, such as the mechanical reels  54  described above, or video reels such as the video reels  54 ′ described above. 
     A winning combination occurs when the symbols appearing along an active payline on the reels  64   a - e  correspond to one of the winning symbol combinations listed in a pay table stored in the system memory  36  of the gaming machine  10  (or on the external systems  50 ). The pay table may also be displayed on the secondary display area  16 , the primary display area  14 , or both and be either displayed constantly, intermittently, or upon request by a player (e.g., by selecting the pay-table button  80 ). Winning combinations listed in the pay table can include three like-symbols appearing on a payline yielding a first payout, four like-symbols appearing on a payline yielding a second, larger payout, five like-symbols appearing on a payline yielding a third, even larger payout, and six like-symbols appearing on an extended payline yielding a fourth, even larger payout. 
     A player may play multiple paylines by selecting the select-lines button  82  until the desired number of paylines is displayed. A gaming machine  10  with a single payline or multiple paylines will work with the present invention. Additionally, a gaming machine  10  with any plurality of reels may also be used in accordance with the present invention. 
     The supplemental single-symbol reel  65  (“reel  65 ”) includes a plurality of symbols similar to or the same as those described above in relation to reels  64   a - e . In one embodiment, the reel  65  is displayed by superimposing a video image of the reel  65  over the reels  64   a - e , which can be either mechanical reels (e.g., mechanical reels  54 ) or video reels (e.g., video reels  54 ′), as mentioned above. In other embodiments, the reel  65  may be a video reel. While the reel  65  is displayed above the reels  64   a - e  on the basic game screen  63 , the reel  65  may be displayed in other locations on the basic game screen  63 , the primary display area  14  or the secondary display area  16 . 
     In some embodiments, the reel  65  is spun each time the reels  64   a - e  are spun. In other embodiments, the reel  65  is spun with the reels  64   a - e  only if a secondary wager is placed in addition to a primary wager placed to spin the reels  64   a - e . The price of the secondary wager to spin the reel  65  may be one-half the primary wager. Other amounts of wagers to spin the reel  65  are also contemplated. Generally, the reel  65  gives the player a chance to improve their win, as will be described below. 
     Referring now to  FIG. 5 , the reels  64   a - e  and the reel  65  are displayed after a play of the basic game. A winning combination is formed along the reels  64   a - e  because three like symbols, the TREASURE BOX symbols  98 , are aligned along the active payline  91 . In accordance with one embodiment of the present invention, if a winning combination is formed on the reels  64   a - e  and the symbol displayed on the reel  65  matches the winning combination, as in the outcome illustrated in  FIG. 5 , the winning combination is extended by one symbol. This is shown by superimposing a video image of the symbol displayed on the reel  65  (i.e., the TREASURE BOX symbol  98 ) onto a position along the winning payline  91 , as illustrated in  FIG. 6 . Thus, in the illustrated embodiment, the winning symbol combination formed by three-like symbols was extended from a three-symbol winning combination to a four-symbol winning combination. If the symbol displayed on the reel  65  does not match the symbols forming the winning symbol combination on the reels  64   a - e , an increased award is not achieved and the award associated with the winning symbol combination on the reels  64   a - e  (i.e., three-like symbols) is awarded. 
     In some embodiments, additional advantageous symbols may be included on the reel  65 . For example, referring now to  FIG. 7 , a “3×” multiplier symbol  109  is displayed on the reel  65  after the reels  64   a - e  and the reel  65  have stopped spinning. If a winning combination is formed along an active payline (e.g., payline  93 ), the “3×” multiplier symbol  109  operates to multiply the winning symbol combination by three, yielding an award three times the amount of the award without the “3×” multiplier symbol  109 . As illustrated in  FIG. 7 , a winning symbol combination is formed on the payline  93  by the three PLATE symbols  108 . The “3×” multiplier symbol  109  thus may be superimposed along the payline  93  over the reels  64   a  or  64   e  and function to increase the award three times the original amount, i.e., three times the amount that would result from a three-PLATE symbol  108  winning combination. 
     Other multiplier symbols may also be used, such as, “2×” resulting in an increased award twice the amount of the original winning symbol combination, “4×” resulting in an increased award four times the amount of the original winning symbol combination, or other integer or non-integer numbers. Other advantageous symbols adapted to combine with a winning symbol combination resulting in an increased award are also contemplated. 
     In some embodiments, a second supplemental single-symbol reel may be added. Referring now to  FIG. 8 , an additional single-symbol reel  111  (“reel  111 ”) is illustrated alongside the first supplemental single-symbol reel  65 . Like the reel  65 , the reel  111  may be displayed as a superimposed image over the reels  64   a - e  or as a purely video reel. Additionally, the location of the reel  111  is not limited to that illustrated in  FIG. 8  and may be displayed anywhere on the main game screen  63 , primary display area  14 , or secondary display area  16 . The second single-symbol reel  111 , in some embodiments, may only be added during a free spin event or a bonus game. 
     The transmissive display  56  may assist in displaying the single-symbol reel  65 , as well as single-symbol reel  111  in some embodiments, on the primary display area  14  with certain types of enhanced graphics upon the occurrence of certain conditions. For example, if the single-symbol reel  65  matches a winning symbol combination, the transmissive display  56  may display the reel  65  as a flashing image, a bursting image, or some other type of interesting graphic to indicate to the player an enhanced winning symbol combination has been earned. The transmissive display  56  may also enhance the reels  64   a - e  by highlighting winning symbol combinations via different colors or otherwise. 
     Each of these embodiments and obvious variations thereof is contemplated as falling within the spirit and scope of the claimed invention, which is set forth in the following claims.

Technology Classification (CPC): 6