Patent Publication Number: US-11651645-B2

Title: Gaming machine with column specific awards

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/555,684, having a filing date of Aug. 29, 2019, the contents of the above-identified application is hereby incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     Gaming machines provide a variety of wagering games such as slot games, video poker games, video blackjack games, roulette games, video bingo games, keno games and other types of games that are frequently offered at casinos and other locations. Playing a primary or base game, hereafter base game, of a gaming machine typically involves a player establishing a credit balance by inputting money or another form of monetary credit, and placing a monetary wager funded by the credit balance on one or more outcomes of an instance or single play of the base game. For many base games, a player may qualify for secondary games, sometimes referred to as bonus games, feature games, or bonus rounds, by attaining a certain winning combination or triggering event in the base game. Secondary games provide an opportunity to win additional game instances, credits, awards, jackpots, progressives, etc. Awards from winning outcomes are typically added back to the credit balance and may be provided to the player upon completion of a gaming session or when the player wants to “cash out.” 
     “Slot” type games are often displayed to the player in the form of various symbols arrayed in a row-by-column grid or matrix. Specific matching combinations of symbols along predetermined paths or paylines through the matrix indicate the outcome of the game. The gaming machine typically highlights winning combinations/outcomes for ready identification by the player. Matching combinations and their corresponding awards are usually shown in a “pay-table” which is available to the player for reference. Often, the player may vary their wager by varying a number of active paylines and/or an amount bet on each active payline. By varying the wager, the player may alter the frequency or number of winning combinations, frequency or number of secondary games, and/or the amount awarded. 
     Typical gaming machines use a random number generator (RNG) to randomly determine the outcome of each game. The game machine is designed to return a certain percentage of the amount wagered back to the player (RTP=return to player) over the course of many plays or instances of the game. The RTP and randomness of the RNG are critical to ensuring the fairness of the games and are therefore highly regulated. Upon initiation of play, the gaming machine, per one or more random numbers generated by the RNG, randomly determines a game outcome and selects symbols which correspond to that outcome. Notably, some gaming machines provide games that may include an element of skill on the part of the player and are therefore not entirely random. 
     SUMMARY 
     Aspects of the present disclosure are directed to a gaming machine and a method of playing a game of such a gaming machine. The gaming machine permits a player to play a base game. During play of the base game, the gaming machine selects symbols for a base game outcome and displays the selected symbols of the base game outcome in columns. The gaming machine further award prizes based on the symbols in the base game outcome. If the base game outcome includes at least a threshold number of a feature trigger symbol, the gaming machine triggers or initiates play of a feature game, and awards a quantity of spins to each feature game column of symbol display positions. 
     During play of the feature game, the gaming machine holds each feature trigger symbol at its respective display position, and if a column has spins remaining, spins/respins reels of the respective feature game column to obtain replacement symbols for each non-feature trigger symbol in the feature game column. For each of the feature game columns, the gaming machine determines, based on the symbols in the feature game column, whether to award a prize associated with the respective feature game column. 
     Advantages, aspects and novel features of the present disclosure, as well as details of an illustrated embodiment thereof, will be more fully understood from the following description and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an exemplary diagram showing several gaming machines networked with various gaming related servers. 
         FIG.  2    is a block diagram showing various functional elements of an exemplary gaming machine. 
         FIGS.  3 A- 3 G  depict base game screens and feature game screens for an example play flow. 
         FIG.  4    depicts exemplary reel strips suitable for selecting base game symbols and/or feature game symbols. 
         FIG.  5    depicts a flowchart for an exemplary method of playing a base game and feature game provided by a gaming machine. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects of the present disclosure are directed to a gaming machine and a method of playing a game of such a gaming machine. During play of a base game, if the base game outcome includes at least a threshold number of a feature trigger symbol, the gaming machine triggers or initiates play of a feature game, and awards a quantity of spins to each feature game column of symbol display positions. During play of the feature game, the gaming machine holds each feature trigger symbol at its respective display position, and if a column has spins remaining, spins/respins reels of the respective feature game column to obtain replacement symbols for each non-feature trigger symbol in the feature game column. For each of the feature game columns, the gaming machine determines, based on the symbols in the feature game column, whether to award a prize associated with the respective feature game column. 
     Embodiments of the present disclosure represent an improvement in the art of electronic gaming machines and software for such electronic gaming machines. For example, at least some embodiments of the present disclosure provide a visual correlation between a jackpot and a game result that resulted in an award of the jackpot. In such embodiments, a jackpot amount may be displayed above or near a column of symbols so as to correlate the jackpot amount with the column. Subsequently, awarding the jackpot amount due to trigger symbols in the column provides an easily perceived and understood visual correlation to the player that the jackpot award was due to the trigger symbols in the column. Thus, embodiments of the present disclosure are not merely new game rules or simply new display patterns, but provide technologic improvements in the art of electronic gaming machines and software for such electronic gaming machines. Moreover, the above example is not intended to be limiting but merely exemplary of technologic improvements provided by some embodiments of the present disclosure. Technological improvements of other embodiments are readily apparent to those of ordinary skill in the art in light of the present disclosure. 
     According to various embodiments of the present disclosure, a gaming machine includes a display device, a memory device, and a processor that executes instructions stored in the memory device. Execution of the instructions causes the processor to at least award a first quantity of spins to a first column of symbol display positions of the display device. Execution of the instructions further causes the processor to, in response to the first quantity of spins indicating at least one spin remains for the first column, spin one or more first reels of the first column to obtain a first column outcome comprising first symbols at respective symbol display positions in the first column. Execution of the instructions further causes the processor to, in response to the first symbols of the first column outcome corresponding to a first winning outcome for the first column, award a first prize associated with the first column. 
     According to further embodiments of the present disclosure, a gaming machine includes a display device, a player input device, a memory device, and a processor that executes instructions stored in the memory device. Execution of the instructions causes the processor to at least receive an input via the player input device to initiate play of a base game. For the play of the base game, execution of the instructions causes the processor to select and display symbols at symbol display positions on the display device. In particular, the processor selects the symbols from a feature trigger symbol and a plurality of non-feature trigger symbols. Execution of the instructions further causes the processor to initiate play of a feature game in response to a predetermined number of the feature trigger symbol being displayed in a base game outcome. For the play of the feature game, execution of the instructions causes the processor to hold each feature trigger symbol at a corresponding feature game symbol display position. The processor further awards a quantity of spins to each feature game column and spins one or more reels associated with each feature game column to select a replacement symbol for each feature game symbol display position that does not display the feature trigger symbol. The processor further awards a prize associated with a feature game column in response to the respective feature game column comprising at least a predetermined number of the feature trigger symbol. 
     According to yet other embodiments of the present disclosure, a method of a gaming machine includes initiating play of a base game in response to receiving an input via a player input device of the gaming machine. For the play of the base game, the method includes selecting and displaying symbols at symbol display positions on a display device of the gaming machine, wherein the symbols are selected from a feature trigger symbol and a plurality of non-feature trigger symbols, and initiating play of a feature game in response to a predetermined number of the feature trigger symbol being displayed in a base game outcome. For the play of the feature game, the method includes holding, in a first feature game column, each feature trigger symbol displayed in a first base game column of the base game outcome, spinning one or more of first reels associated with the first feature game column to select a first replacement symbol for each non-feature trigger symbol in the first feature game column, and awarding a first prize associated with the first feature game column in response to the first feature game column comprising at least a first predetermined number of the feature trigger symbol. 
     Various aspects of the present disclosure may be embodied in many different forms and should not be construed as being limited to the example embodiments set forth herein. Rather, these example embodiments of the disclosure are provided so that this disclosure will be thorough and complete and will convey various aspects of the disclosure to those skilled in the art. 
     As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise,” “include,” “comprising,” and “including,” when used in this specification, specify the presence of stated features, numbers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, elements, components, and/or groups thereof. 
     It will be understood that, although the terms first, second, etc. may be used herein to describe various features, steps, operations, elements, and/or components, these features, steps, operations, elements, and/or components should not be limited by these terms. These terms are only used to distinguish one feature, step, operation, element, and/or component from another. Thus, for example, a first feature, a first step, a first operation, a first element, and/or a first component discussed below could be termed a second feature, a second step, a second operation, a second element, and/or a second component without departing from the teachings of the present disclosure. 
     Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper,” and the like, are used herein for ease of description to describe a relationship of an element and/or feature to another element and/or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may be interpreted accordingly. 
     Furthermore, the term “and/or” means any one or more of the items in the list joined by “and/or”. As an example, “x and/or y” means any element of the three-element set {(x), (y), (x, y)}. As another example, “x, y, and/or z” means any element of the seven-element set {(x), (y), (z), (x, y), (x, z), (y, z), (x, y, z)}. 
     Referring now to  FIG.  1   , several different models of gaming machines are illustrated, which may be networked to various gaming related servers. In particular,  FIG.  1    shows a system  100  in a gaming environment that includes one or more server computers  102  (e.g., slot servers of a casino) that are in communication, via a communications network, with one or more gaming machines  104 A- 104 X (slot machines, video poker machines, bingo machines, etc.) that may implement one or more aspects of the present disclosure. Also, aspects of the present disclosure may be implemented by a portable and/or remote gaming device such as, but not limited to, a smart phone, a tablet, a laptop, or a game console. However, such gaming devices may require specialized software and/or hardware to comply with regulatory requirements regarding devices used for wagering or games of chance in which monetary awards are provided. 
     Communication between and/or among the gaming machines  104 A- 104 X and the server computers  102  may be direct or indirect, such as over the Internet through a website maintained by a computer on a remote server and/or over an online data network including commercial online service providers, Internet service providers, private networks, and the like. In other embodiments, the gaming machines  104 A- 104 X may communicate with one another and/or the server computers  102  over radio frequency (RF) links, cable TV links, satellite links, and/or the like. 
     In some embodiments, server computers  102  may not be necessary and/or preferred. For example, in one or more embodiments, a stand-alone gaming machine such as gaming machine  104 A, gaming machine  1048 , and/or any of the other gaming machines  104 C- 104 X may implement one or more aspects of the present disclosure. However, it is typical to find multiple gaming machines connected to networks implemented with one or more of the different server computers  102  described herein. 
     The server computers  102  may include a central determination gaming system server  106 , a ticket-in-ticket-out (TITO) system server  108 , a player tracking system server  110 , a progressive system server  112 , and/or a casino management system server  114 . Gaming machines  104 A- 104 X may include features to enable operation of any or all servers for use by the player and/or operator (e.g., the casino, resort, gaming establishment, tavern, pub, etc.). For example, game outcomes may be generated on a central determination gaming system server  106  and then transmitted over the network to any of a group of remote terminals or remote gaming machines  104 A- 104 X that utilize the game outcomes and display the results to the players. 
     The gaming machine  104 A may provide a cabinet construction which may be aligned in rows or banks of similar devices for placement and operation on a casino floor. The gaming machine  104 A may include a main door  154  which provides access to the interior of the cabinet. The gaming machine  104 A may also include a player interface  120  that is accessible by a player of the gaming machine  104 A and that is configured with input switches or buttons  122 , an access channel for a bill validator  124 , and/or an access channel for a ticket-out printer  126 . 
     In  FIG.  1   , the gaming machine  104 A is shown as a Relm XL™ model gaming machine manufactured by Aristocrat® Technologies, Inc. As shown, the gaming machine  104 A is a reel machine having a gaming display area  118  comprising a number (typically 3 or 5) of mechanical reels  130  with various symbols displayed on them. The reels  130  are independently spun and stopped to show a set of symbols within the gaming display area  118 , which may be used to present a game outcome comprising a plurality of symbols. 
     In many configurations, the gaming machine  104 A may include a main display device  128  mounted to, or above, the gaming display area  118 . The main display device  128  may include a high-resolution LCD display device, a plasma display device, an LED display device, or an OLED display device, a cathode ray tube (CRT) display device, and/or another video display device. Furthermore, the main display device  128  may be flat or curved as shown. 
     In some embodiments, the bill validator  124  may also function as a “ticket-in” reader that allows the player to use a casino issued credit ticket to load credits onto the gaming machine  104 A (e.g., in a cashless ticket (“TITO”) system). In such cashless embodiments, the gaming machine  104 A may also include a “ticket-out” printer  126  for outputting a credit ticket when a “cash out” button of the player interface  120  is pressed. Cashless TITO systems are used to generate and track unique bar-codes and/or other indicators printed on tickets to allow players to avoid the use of bills and coins by loading credits using a ticket reader and cashing out credits using a ticket-out printer  126  on the gaming machine  104 A. The gaming machine  104 A may also include hardware meters to track, monitor, and/or otherwise record various game-related data. For example, the gaming machine  104 A may include hardware meters that monitor a player credit balance and that records a total amount of money wagered, a total amount of money deposited, a total amount of money withdrawn, and/or a total amount of winnings for gaming machine  104 A. Such hardware meters may further ensure that the gaming machine  104 A maintains regulatory compliance. 
     In some embodiments, a player tracking card reader  144 , a transceiver for wireless communication with a player&#39;s smartphone, a keypad  146 , and/or an illuminated display  148  for reading, receiving, entering, and/or displaying player tracking information is provided in gaming machine  104 A. In such embodiments, a game controller within the gaming machine  104 A may communicate with the player tracking system server  110  to send and receive player tracking information. 
     The gaming machine  104 A may also include a bonus topper wheel  134 . When bonus play is triggered (e.g., by a player achieving a particular outcome or set of outcomes in the primary game), bonus topper wheel  134  is operative to spin and stop with indicator arrow  136  indicating the outcome of the bonus game. Bonus topper wheel  134  is typically used to play a bonus game, but it could also be incorporated into play of the base or primary game. 
     A candle  138  may be mounted on the top of the gaming machine  104 A and may be activated by a player (e.g., using a switch or one of buttons  122  of player interface  120 ) to indicate to operations staff that the gaming machine  104 A has experienced a malfunction or that the player requires service. The candle  138  may also be used to indicate a jackpot has been won and to alert staff that a hand payout of an award may be needed. 
     The gaming machine  104 A may also include one or more information panels  152  which may be a back-lit, silkscreened glass panel with lettering to indicate general game information. Such general game information may include, for example, game denominations (e.g., $0.25 or $1), paylines, pay-tables, and/or various game related graphics. In some embodiments, the gaming machine  104 A may implement the information panel(s)  152  via additional video display devices. 
     The gaming machine  104 A may also include a handle  132 . The handle  132  may be mounted on a side of a main cabinet  116  for the gaming machine  104 A. In some embodiments, a player may pull the handle  132  to initiate play of a game provided by the gaming machine  104 A. 
     Many or all the above described components may be controlled by circuitry (e.g., a gaming controller) housed inside the main cabinet  116  of the gaming machine  104 A. Details of example circuitry are shown in  FIG.  2   . 
     Note that not all gaming machines suitable for implementing embodiments of the present disclosure necessarily include top wheels, top boxes, information panels, cashless ticket systems, and/or player tracking systems. Further, some suitable gaming machines have only a single game display that includes only a mechanical set of reels and/or a video display. Other suitable gaming machines may be designed for bar counters or table tops and have displays that face upwards. 
     An alternative example gaming machine  1048  illustrated in  FIG.  1    is the Arc™ model gaming machine manufactured by Aristocrat® Technologies, Inc. Note that where possible, similar features of the gaming machine  104 A and the gaming machine  1048  are identified using the same reference numbers. As depicted, the gaming machine  104 B does not include physical reels and instead shows game play functions on main display device  128 . An optional topper display device  140  may be used as a secondary game display device for bonus play, to show game features or attraction activities while a game is not in play, or any other information or media desired by the game designer or operator. In some embodiments, topper display device  140  may also or alternatively be used to display progressive jackpot prizes available to a player during play of gaming machine  104 B. 
     The gaming machine  1048  may include a main cabinet  116  including a main door or service door  154 , which opens to provide access to an interior of the gaming machine  104 B. The main door  154  may be used by service personnel to refill the ticket-out printer  126  and collect bills and tickets inserted into the bill validator  124 . The main door  154  may also be accessed to reset the gaming machine  104 B, verify and/or upgrade software of the gaming machine  104 B, and/or for general maintenance of the gaming machine  104 B. 
     Another example gaming machine  104 C shown is the Helix™ model gaming machine manufactured by Aristocrat® Technologies, Inc. The gaming machine  104 C may include main display device  128 A that is in a landscape orientation. Although not illustrated by the front view provided, the main display device  128 A may have a curvature radius from top to bottom, or alternatively from side to side. In some embodiments, the main display device  128 A may include a flat panel display. The main display device  128 A may be used for base or primary game play while secondary display device  1288  may be used for secondary or feature game play, to show game features or attraction activities while the game is not in play, and/or any other information or media desired by the game designer or operator. In some embodiments, the gaming machine  104 C may also include speakers  142  to output various audio such as game sound, background music, etc. 
     Many different types of games, including mechanical slot games, video slot games, video poker, video black jack, video pachinko, keno, bingo, and lottery, may be provided with or implemented within the depicted gaming machines  104 A- 104 C and other similar gaming machines. Each gaming machine  104 A- 104 C may also be operable to provide many different games. Games of the gaming machines  104 A- 104 C may be differentiated by themes, sounds, graphics, type of game (e.g., slot game vs. card game vs. game with aspects of skill), denomination, number of paylines, maximum jackpot, progressive or non-progressive awards, bonus games, and/or class (e.g., Class  2 , Class  3 , etc. embodiments). 
       FIG.  2    provides a block diagram depicting exemplary internal electronic components of a gaming machine  200  connected to various external systems. All or parts of the example gaming machine  200  shown could be used to implement any one of the example gaming machines  104 A-X depicted in  FIG.  1   . The gaming machine  200  includes a game controller  202  that controls play of one or more games provided by the gaming machine  200 . To this end, the game controller  202  includes one or more processors  204  and memory  208  coupled to the one or more processors  204 . The memory  208  may store game software or a program  206  having instructions that are executed by the one or more processors  204  to control operation of the gaming machine  200  and play of games provided by the gaming machine  200 . The memory  208  may include one or more mass storage devices or media that are housed within gaming machine  200 . Within the mass storage devices and/or memory  208 , one or more databases  210  may be provided for use by processor  204  when executing instructions of the program  206 . 
     The gaming machine  200  may further includes a random number generator (RNG)  212 . The RNG  212  may be implemented in hardware and/or software. Moreover, the RNG  212  may generate random numbers that are used in the operation of game play to ensure that game play outcomes are random and meet regulations for a game of chance. Alternatively, a game instance (i.e. a play or round of the game) may be generated on a remote gaming machine such as a central determination gaming system server  106  (see  FIG.  1   ). The game instance is communicated to gaming machine  200  via the network  214  and then displayed on gaming machine  200 . Gaming machine  200  may execute game software, such as but not limited to video streaming software that allows the game to be displayed on gaming machine  200 . When a game is stored on gaming machine  200 , it may be loaded from a memory  208  (e.g., from a read only memory (ROM)) or from the central determination gaming system server  106  to memory  208 . The memory  208  may include RAM, ROM or another form of storage media that stores instructions for execution by the processor  204 . 
     The gaming machine  200  may include a topper display device  216  or another form of a top box (e.g., a topper wheel, a topper display device, etc.) which sits above cabinet  218 . The cabinet  218  or topper display device  216  may also house a number of other components which may be used to add features to a game being played on gaming machine  200 , including speakers  220 , a ticket printer  222  which prints bar-coded tickets or other media or mechanisms for storing or indicating a player&#39;s credit value, a ticket reader  224  which reads bar-coded tickets or other media or mechanisms for storing or indicating a player&#39;s credit value, and a player tracking interface  232 . The player tracking interface  232  may include a keypad  226  for entering information, a player tracking display  228  for displaying information (e.g., an illuminated panel or video display device), a card reader  230  for receiving data and/or communicating information to and from media or a device such as a smart phone enabling player tracking. Ticket printer  222  may be used to print tickets for a TITO system server  108 . The gaming machine  200  may further include a bill validator  234 , player-input buttons  236  of a player interface, cabinet security sensors  238  to detect unauthorized opening of the cabinet  218 , a primary game display device  240 , and a secondary game display device  242 , each coupled to and operable under the control of game controller  202 . 
     The gaming machine  200  may be connected over network  214  to player tracking system server  110 . The player tracking system server  110  may be, for example, an OASIS® system manufactured by Aristocrat® Technologies, Inc. The player tracking system server  110  may be used to track play (e.g. amount wagered, games played, time of play, and/or other quantitative or qualitative measures) for individual players so that an operator may reward players in a loyalty program. The player may use the player tracking interface  232  to access his/her account information, activate free play, and/or request various information. Player tracking and loyalty programs seek to reward players for their play and help build brand loyalty to the gaming establishment. The rewards typically correspond to the player&#39;s level of patronage (e.g., the player&#39;s playing frequency and/or total amount of game plays at a given casino). Player tracking rewards may include complimentary and/or discounted meals, meals, lodging, entertainment, and/or plays. Player tracking information may be combined with other information that is now readily obtainable by a casino management system. 
     The gaming machines, such as gaming machines  104 A- 104 X,  200 , are highly regulated to ensure fairness and, in many cases, gaming machines  104 A- 104 X,  200  are operable to award monetary awards (e.g., typically dispensed in the form of a redeemable voucher). Therefore, to satisfy security and regulatory requirements in a gaming environment, hardware and software architectures are implemented in gaming machines  104 A- 104 X,  200  that differ significantly from those of general-purpose computers. Adapting general purpose computers to function as gaming machines  200  is not simple or straightforward because of: 1) the regulatory requirements for gaming machines  200 ; 2) the harsh environment in which gaming machines  200  operate; 3) security requirements; 4) fault tolerance requirements; and 5) special purpose componentry used to enable functionality of a gaming machine. These differences require substantial engineering effort with respect to game design implementation, hardware components, and/or software. 
     When a player wishes to play the gaming machine  200 , he/she may insert cash or a ticket voucher through a coin acceptor (not shown) or bill validator  234  to establish a credit balance on the gaming machine  200 . The player may use the credit balance to place wagers on instances of the game and to receive credit awards based on the outcome of winning instances. The gaming machine  200  may decrease the credit balance by the amount of each wager and may increase the credit balance upon a win. Moreover, the player may add additional credits to the balance at any time. The player may also optionally insert a loyalty club card into the card reader  230 . During the game, the player may view the game outcome on one or more of the primary game display devices  240  and secondary game display devices  242 . The gaming machine  200  may display other game and prize information via display devices  240 ,  242  and/or other display devices. 
     For each game instance, a player may make selections, which may affect play of the game. For example, the player may vary the total amount wagered by selecting the amount bet per active payline and selecting the number of active paylines. In many games, the gaming machine  200  requests the player to initiate or select options during course of game play such as, for example, spinning a wheel to begin a bonus round, selecting various items during a feature game, etc. The player may make these selections using the player-input buttons  236 , a touch screen of the primary game display device  240 , and/or some other input device of a player interface that enables a player to input information into the gaming machine  200 . 
     During certain game events, the gaming machine  200  may present visual and auditory effects that may be perceived by the player. These effects add to the excitement of a game, which makes a player more likely to enjoy the playing experience. Auditory effects include various sounds that are projected by the speakers  220 . Visual effects may include flashing lights, strobing lights, and/or other patterns displayed from lights on the gaming machine  200 , from lights behind the information panel  152  ( FIG.  1   ), and/or from lights separate from the gaming machine  200  which are provided in the area surrounding the gaming machine  200 . 
     When the player is done, the player may cash out the credit balance by, for example, pressing a cash out button of the player interface to receive a ticket from the ticket printer  222 . The ticket may be “cashed-in” for money or inserted into another machine to establish a credit balance for play. 
     In some embodiments, the gaming machine  200  may implement a slot-type or reel-type base game, play of which may trigger a slot-type or reel-type feature game as shown in  FIGS.  3 A- 3 G . In the interest of clarity, the following describes base game and feature game of  FIGS.  3 A- 3 G  as implemented by gaming machine  200 . Each of gaming machines  104 A- 104 X, however, may implement the base game and/or feature of  FIGS.  3 A- 3 G  via a similar manner. As shown in  FIG.  3 A , the gaming machine  200  may generate and present a base game screen  300  via display device  240 . The base game screen  300  may include a prize display area  310  that identifies one or more prize indicia  312   1 - 312   5  and the current prize value  314   1 - 314   5  of prizes associated with such indicia. For example, as shown in  FIG.  3 A , the prize display area  310  may display a mini prize indicia  312   1  and mini prize value  314   1 , a minor prize indicia  312   2  and minor prize value  314   2 , a maxi prize indicia  312   3  and maxi prize value  314   3 , a major prize indicia  312   4  and major prize value  314   4 , and a grand prize indicia  312   5  and grand prize value  314   5 . 
     In some embodiments, one or all of the mini prize value  314   1 , the minor prize value  314   2 , the maxi prize value  314   3 , the major prize value  314   4 , and the grand prize value  314   5  may be implemented as progressive jackpots, as fixed bonus amounts that do not increment, or as a mixture of both. In one embodiment, the grand prize value  314   5  is implemented as a linked progressive jackpot, while the major prize value  314   4  is implemented as a standalone progressive (SAP) jackpot which only takes contributions from the gaming machine itself, incrementing the jackpot as a function of an amount of coin-in or wagers. In the same embodiment, the mini prize value  314   1  and the minor prize value  314   2  are implemented as fixed bonus amounts that are based on the initial bet wagered and increase as the wager amount increases. In some embodiments, the grand prize value  314   5  may also be implemented as a standalone progressive jackpot, or the major prize value  314   4  may be implemented as a linked progressive jackpot. 
     The base game screen  300  may further include a base game outcome area  330  via which the gaming machine  200  may present a base game outcome  332 . To this end, the base game outcome area  330  may include one or more base game symbol display positions  334  via which base game symbols of the base game outcome  332  are presented. In particular, the base game symbol display positions  334  may be arranged in base game columns  340   1 - 340   5 , resulting in the base game symbols of the base game outcome  332  being presented in the base game columns  340   1 - 340   5 . The base game symbols of the base game outcome  332  may include instances of a feature trigger symbol  320  and one or more instances of a non-feature trigger symbols  328 . 
     The base game outcome area  330  may further associate each base game column  340   1 - 340   5  with a particular prize presented in the prize display area  310 . More specifically, the base game outcome area  330  may include a base game prize tab  342   1 - 342   5  for each base game column  340   1 - 340   5 . Each base game prize tab  342   1 - 342   5  may identify which of the prizes in the prize display area  310  is associated with its respective base game column  340   1 - 340   5 . In one embodiment, the base game prize tab  342   1 - 342   5  may present such association by including the same prize indicia  344   1 - 344   2  (e.g., prize values and/or prize names) as the associated prize in the prize display area. For example, the base game prize tab  342   1  may associate the first base game column  340   1  with the mini prize by presenting a prize indicia  344   1  of $10.00 that is the same as the mini prize value  314   1  associated with the mini prize indicia  312   1 . 
     In other embodiments, the base game prize tabs  342   1 - 342   5  may further convey such prize associations via other ways such as by including corresponding prize indicia, icon, etc. For example, the base game prize tabs  342   1 - 342   5  may further convey the prize associations via coordinating colors. In particular, the prize display area  310  may present each prize indicia  312   1 - 312   5  and its prize value  314   1 - 314   5  in a different color. The base game prize tabs  342   1 - 342   5  may likewise display their prize indicia  344   1 - 344   5  via matching colors. For example, the mini prize indicia  312   1  and its prize value  314   1  may be presented via a purple color and the base game prize tab  342   1  may likewise present the prize indicia  344   1  via the same purple color. Conversely, the grand prize indicia  312   5  and its prize value  314   5  may be presented via a red color and the base game prize tab  342   5  may likewise present the prize indicia  344   5  via the same red color. Thus, the gaming machine  200  may further identify which prizes are associated with which columns via coordinating colors. 
     The base game screen  300  may further include a status area  350  that provides various status information. For example, the status area  350  may provide a credit balance meter  352  that reflects the credit balance established on the gaming machine  200 , an amount bet indicator  354  that reflects an amount bet on a play of the base game, a base game win meter  356  that reflects credits won from play of the base game, and a monetary denomination indicator  358  that reflects the monetary denomination associated with each credit. 
     Besides the base game screen  300 , the gaming machine  200  may generate and present a feature game screen  360  via display device  240 . See, e.g.,  FIG.  3 C . Similar to the base game screen  300 , the feature game screen  360  may include a prize display area  362  that identifies one or more prize indicia  312   1 - 312   5  and the current prize value  314   1 - 314   5  associated with such indicia. For example, as shown in  FIG.  3 C , the prize display area  362  may display the mini prize indicia  312   1  and the mini prize value  314   1 , the minor prize indicia  312   2  and the minor prize value  314   2 , the maxi prize indicia  312   3  and the maxi prize value  314   3 , the major prize indicia  312   4  and the major prize value  314   4 , and the grand prize indicia  312   5  and the grand prize value  314   5 . 
     The feature game screen  360  may further include a feature game outcome area  370  via which the gaming machine  200  may present a feature game outcome  372 . To this end, the feature game outcome area  370  may include one or more feature game symbol display positions  374  via which feature game symbols of the feature game outcome  372  are presented. In particular, the feature game symbol display positions  374  may be arranged in feature game columns  380   1 - 380   5 , resulting in the feature game symbols of the feature game outcome  372  being presented in the feature game columns  380   1 - 380   5 . The feature game symbols of the feature game outcome  372  may include instances of the feature trigger symbol  320  and one or more instances of the non-feature trigger symbols  320 . 
     The feature game outcome area  370  may further associate each feature game column  380   1 - 380   5  with a particular prize presented in the prize display area  362 . More specifically, the feature game outcome area  370  may include a feature game prize tab  392   1 - 392   5  for each feature game column  380   1 - 380   5 . Each feature game prize tab  392   1 - 392   5  may identify which of the prizes in the prize display area  362  is associated with its respective feature game column  380   1 - 380   5 . In one embodiment, the feature game prize tabs  392   1 - 392   5  may present such association via prize indicia  394   1 - 394   5  and/or colors in a manner similar to the base game prize tabs  342   1 - 342   5 . However, the feature game prize tabs  392   1 - 392   5  further include spin indicia  396   1 - 396   5  that identify a quantity of spins awarded to its respect feature game column  380   1 - 380   5 . In one embodiment, the gaming machine  200  visually expands or morphs the base game prize tabs  342   1 - 342   5  into the feature game prize tabs  392   1 - 392   5  such that the resulting feature game prize tabs  392   1 - 392   5  include the information of base game prize tabs  342   1 - 342   5  as well as the spin indicia  396   1 - 396   5 . 
     Like the base game screen  300 , the feature game screen  360  may further include the status area  350 . Via such status area, the feature game screen  360  may indicate the credit balance meter  352 , the amount bet indicator  354 , the base game win meter  356 , and the monetary denomination indicator  358 . In addition to the status area  350 , the feature game screen  360  may further include a feature game win meter  359  via which the gaming machine  200  may indicate an amount won during play of the feature game. 
     The base game screen  300  and feature game screen  360  are depicted in  FIGS.  3 A- 3 G  as having the same number of columns and the same arrangement of symbol display positions. However, the base game screen  300  and the feature game screen  360  in some embodiments may be implemented such that the base game and feature game do not have the same number of columns and/or the same arrangement of symbol display positions. In some embodiments, the height of the columns may vary from the base game and feature game. For example, the height of the columns (and the quantity of symbol display positions in each column) may be greater in the feature game than in the base game. 
     As noted above, the gaming machine  200  generates and displays the base game outcome  332  and the feature game outcome  372 . To this end, the gaming machine  200  may spin reels associated with the base game columns  340   1 - 340   5 , feature game columns  380   1 - 380   5 , base game symbol display positions  334 , and/or feature game symbols display positions  374 . In at least one embodiment, each base game column  340   1 - 340   5  has its own symbol-carrying reel that supplies its column of base game symbol display positions  334  with base game symbols. Furthermore, each feature game symbol display position  374  has its own symbol-carrying reel that supplies its feature game symbol display position  374  with a feature game symbol. 
     In such an embodiment, as shown in  FIG.  3 A , the base game symbols of the base game screen  300  may be provided via five symbol-carrying reels that each provide symbols for the four (4) base game symbol display positions  334  in its respective column, whereas the feature game symbols of the feature game screen  360  may be provided via twenty (20) symbol-carrying reels. In various embodiments, the number of reels per column may range between a single reel per column to up to a separate reel per symbol display position. Thus, for the 4×5 base game outcome  332  of  FIG.  3 A , between five (5) and twenty reels may be used to provide the base game symbols. Likewise, for the 4×5 feature game outcome  372  of  FIG.  3 C , between five (5) and twenty (20) reels may be used to provide the feature game symbols in various embodiments. Furthermore, while base outcome  332  and a feature game outcome  372  are depicted as providing 4×5 arrays of symbol display positions, embodiments may provide base game outcomes and/or feature game outcomes having a different arrangement (e.g., 3×3, 3×5, 5×5, etc.) of symbol display positions. Moreover, the feature game outcome may have a different arrangement of symbols than the base game outcome. 
     Turning now to  FIG.  4   , details are presented regarding reel strips  410 A- 410 E that the gaming machine  200  may use to generate the base game outcome  332  and/or feature game outcome  372 . As shown, each reel strip  410 A- 410 E provides an ordered set of game symbols  430 . In the depicted embodiment, the predetermined symbol set consists of seven different game symbols  430 , which are represented by different letters (e.g. A, B, C, D, E, F, G) for ease of illustration. However, other embodiments may utilize a predetermined symbol set consisting of a different number of game symbols  430 . Moreover, the game symbols  430  may take on other shapes that may align with a particular theme of the gaming machine  200 . See, e.g., symbols of  FIGS.  3 A- 3 G . 
     As further shown, each reel strip  410 A- 410 E may include an ordered symbol set consisting of a fixed number of game symbols  430  that are arranged in a predefined order. In some embodiments, each reel strip  410 A- 410 E may include the same fixed number of game symbols  430 . However, in the depicted embodiment, each reel strip  410 A- 410 E may provide an ordered symbol set having a different fixed number of game symbols  430 . The ordered symbol set of each reel strip  410 A- 410 E may be predetermined, predefined, or randomly determined for one or more reel spins. Moreover, the gaming machine  200  may include multiple reel sets, wherein each reel set may comprise a different number of reel strips, carry different game symbols, specify a different order of game symbols, specify a different proportion of feature trigger symbols  320  to non-feature trigger symbols  328 , etc. Furthermore, while the reel strips  410 A- 410 E are depicted as a linear set of symbols, the game machine  200  utilizes the reel strips  410 A- 410 E in a circular manner such that the first reel stop (e.g., reel stop 0 of reel strip  410 A) is adjacent to the last reel stop (e.g., reel stop 16 of reel strip  410 A). 
     Thus, the gaming machine  200  may generate a base game outcome  332  by assigning a reel strip to each reel of the base game and using the RNG  212  to randomly select a reel stop position for each assigned reel strip. The gaming machine  200  may then cause the display device  240  to spin base game symbols through the respective base game display position(s)  334  per the order specified by the assigned reel strip and stop the spinning of such base game symbols at the randomly selected reel stop position. Similarly, the gaming machine  200  may generate a feature game outcome  372  by assigning a reel strip to each reel of the feature game and using the RNG  212  to randomly select a reel stop position for each assigned reel strip. The gaming machine  200  may then cause the display device  240  to spin feature game symbols through the respective feature game display position(s)  374  per the order specified by the assigned reel strip and stop the spinning of such feature game symbols at the randomly selected reel stop position. 
     In some embodiments, sets of symbols and/or reel strips are stored in memory  208 . Such symbols may include at least one feature trigger symbol  320  and a plurality of non-feature trigger symbols  328 . In some embodiments, the feature trigger symbol  320  is implemented as a configurable symbol and the non-feature trigger symbols are implemented as non-configurable symbols. Per a configurable symbol implementation, the feature trigger symbol  320  includes a common component  322  and a variable component  324 . See, e.g.,  FIG.  3 A . The variable component  324  may identify an award associated with the feature trigger symbol  320 . For example, the variable component  324  may be a numeric value that specifies an award amount for the feature trigger symbol  320 . For other instances, the variable component  324  may be a textual label that specifies a particular jackpot, progressive jackpot, or other award, such as an award amount. In some embodiments, a reel strip may include one or more instances of the feature trigger symbol  320  in which the variable component  324  is fixed for that particular instance of the feature trigger symbol  320 . In some embodiments, a reel strip may include one or more instances of the feature trigger symbol  320  in which the variable component  324  is not-fixed for that particular instance of the feature trigger symbol  320 . In such embodiments, the processor  204  may randomly select the variable component  324  for each instance of the feature trigger symbol  320  before or after selecting a reel stop position for the reel strip. 
     Values for the variable components  324  may be determined using various different techniques. For example, multiple sets of reel strips may be stored in memory  208  and the values for the variable components  324  of one or more of such sets may be predefined. The processor  204  may then select a set of reel strips from the multiple sets of stored reel strips based on various criteria such as, for example, an amount bet, the selected denomination (1¢, 5¢, 10¢, etc.) of the game, whether a max bet was placed, a number of active paylines, a randomly generated number, etc. In some embodiments, one or more tables may be stored in the memory  208 . The processor  208  may use one or more of such tables to generate the values for the variable components  324 . Similar to the reel sets above, the processor  204  may select a table from the stored tables based on various criteria such as, for example, an amount bet, the selected denomination (1¢, 5¢, 10¢, etc.) of the game, whether a max bet was placed, a number of active paylines, a randomly generated number, etc. The selected table may provide a weighted table of multiplier values. In such an embodiment, the processor  204  may randomly select multiplier values from the table in a weighted manner (i.e., some multiplier values are more likely to be selected than others) and generate values for variable components  324  by multiplying a denomination value or a wager amount by the selected multiplier values. In other embodiments, the selected table may provide a weighted table of values. In such embodiments, the processor  204  may randomly select values from the table in a weighted manner (i.e., some values are more likely to be selected than others) and use the values selected from the table for the values of the variable components  324 . Other techniques for generating or predefining the values of the variable components  324  are possible. 
     Examples of the feature trigger symbol  320  implemented as a configurable symbol are shown in  FIGS.  3 A- 3 E . As shown, the feature trigger symbol  320  includes a common component  322  depicted as a dollar symbol and a variable component  324  depicted as indicia overlaying the common component  322 . However, in some embodiments, the feature trigger symbol  320  may be implemented as a non-configurable symbol (e.g., without a common component  322  and a variable component  324 ). In the depicted embodiments of  FIGS.  3 A- 3 E , the indicia of the variable components  324  are numeric values directly indicative of a value or number of credits associated with the particular instance of the feature trigger symbol  320 . In other embodiments, the indicia may indirectly indicate the value or number of credits of a prize associated with the particular instance of the feature trigger symbol  320 . For example, the indicia may include textual labels such as “grand,” “major,” “maxi,” “minor,” or “mini” to indicate prizes whose values respectively correspond to current values for grand, major, maxi, minor, and mini progressive jackpot prizes. 
     The indicia of the variable component  324  may also take other forms. For example, a car icon or car textual label may indicate that the player has the opportunity to win or car or has won a car. In some embodiments, such indicia may indicate only a portion of a prize. Continuing with the car example, the car icon may be split into four portions, each portion being assigned to a different feature trigger symbol  320 . In such embodiments, a game outcome must include all four portions of the car icon in order to win the car prize. 
     In one embodiment, numeric values of the variable components  324  may be generated by randomly selecting one of a plurality of predefined multipliers for each variable component  324  and applying the selected multiplier to an amount wagered on the base game to obtain the numeric value for the respective variable component  324 . In such an embodiment, the multipliers may be randomly selected according to a weighted probability based at least in part on the amount wagered on the base game. In an embodiment, the processor  204  may assign the variable components  324  after the configurable symbols have been selected for display but before the display device  240  displays the selected configurable symbols. In another embodiment, the processor  204  may assign values to the configurable symbols after the display device  240  displays the configurable symbols. 
     In some embodiments, a predefined value and/or a jackpot may be randomly selected for a variable components  324 . As used herein, the term “jackpot”, as opposed to “prize”, refers to a progressive award which accumulates over multiple plays of the base game and/or the feature game. As will be appreciated, the jackpots may be funded from a variety of sources including funding from only plays of the gaming machine  200  itself, and/or funding from plays of a plurality of linked gaming machines  200 . Furthermore, the jackpot may be triggered by any means known in the art such as by using a mystery trigger. 
     Referring now to  FIG.  5   , details regarding a gaming machine and a game provided by such gaming machine are described. In particular, a flowchart is depicted in  FIG.  5   , which illustrates a general flow of the method  500  of playing a base game and feature game provided by a gaming machine. In the interest of clarity, the method  500  is described from the standpoint of gaming machine  200  of  FIG.  2   . However, it should be appreciated that the method  500  may be implemented in a similar manner by other gaming machines such as gaming machines  104 A- 104 X of  FIG.  1   . In various embodiments, the method  500  is executed by a processor, such as processor  204 . 
     At a high-level, the gaming machine  200  per the method  500  permits a player to play a base game and a feature game that may be triggered or initiated through play of the base game. During play of the base game, the gaming machine  200  may select symbols for a base game outcome  332  and display the symbols of the base game outcome  332 . The gaming machine  200  may award prizes based on the symbols in the base game outcome  332 . If a trigger condition occurs such as, for example, the base game outcome  332  including at least a threshold number of a feature trigger symbol  320 , the gaming machine  200  triggers or initiates play of the feature game, awards each feature game column with a quantity of spins, and holds each feature trigger symbol of the base game outcome  332  at its respective feature game symbol display position  374 . In various embodiments, if a trigger condition, such as the base game outcome including a threshold number of feature trigger symbols, does not occur, but a number of feature trigger symbols occur in the base game outcome that is less than the threshold number requirements to trigger the feature game, but greater than a second minimum threshold, then the gaming machine may cause an increase of one or more of the column prizes. For example, if the threshold number required to trigger the feature is 3, and the base game outcome includes 2 feature trigger symbols (which is greater than a second minimum threshold of one), then the column prizes associated with the 2 feature trigger symbols are incremented. The value of the increment may be predetermined for each column prize, randomly determined, determined based on the value displayed on the feature trigger symbols, etc. In certain embodiments, only certain predetermined or randomly determined column prizes may be incremented. 
     During play of the feature game, the gaming machine  200  holds each feature trigger symbol in its respective feature game symbol display position and, if a feature game column  380   1 - 380   5  has remaining spins, spins/respins reels of the respective column to obtain replacement symbols for each feature game symbol display position  374  without the feature trigger symbol  320 . Each of the feature game columns  380   1 - 380   5  has a prize that is specifically associated to that feature game column. For each of the feature game columns  380   1 - 380   5 , the gaming machine  200  may determine whether to award the prize for the respective feature column based on the symbols in the feature game column. Further details and alternative embodiments of the gaming machine  200 , the base game, and/or the feature game are presented below. 
     Turning now to the flowchart of  FIG.  5   , the gaming machine  200  at  502  may receive input that specifies a wager on a base game. The gaming machine  200  may further receive input that initiates play of the base game. For example, a player via the player interface of the gaming machine  200  may specify a number of credits of an established credit balance to wager on play of the base game. Further, the player, via the player interface (e.g., pressing a button  236 , pulling a handle, touching a touch screen, etc.), may initiate play of the base game. 
     At  504 , the processor  204  of the gaming machine  200  may select base game symbols for a base game outcome  332  and cause the primary game display device  240  to display the base game symbols of the base game outcome  332  at respective base game symbol display positions  334 . See, e.g.,  FIG.  3 A . As explained above, the processor  204  may select the symbols of the base game outcome  332  by randomly selecting reel stop positions for each base game reel and its respective base game reel strip. The processor  204  at  506  may further assign values to variable components  324  of any displayed feature trigger symbols  320 . As explained above, the processor  204  in some embodiments may assign values to variable components  324  prior to displaying the base game symbols at  504 . 
     The processor  204  at  508  may determining whether the base game outcome  332  includes any winning symbol combinations along an activate payline. For each such winning symbol combination, the processor  204  may award a prize associated with the winning symbol combination. For example, the processor  204 , in one embodiment, may provide an award of ten (10) credits for four “10” symbols aligned along payline  302 . See, e.g., payline  302  of  FIG.  3 A . 
     At step  510 , the processor  204  may determine whether a feature trigger event has occurred. In some embodiments, the processor  204  may determine that the trigger event has occurred if a base game outcome  332  includes at least a threshold number (e.g., four) of feature trigger symbols  320 . Alternatively or additionally, the processor  204  may determine that the feature trigger event has occurred if a predetermined number (such as three or more) of base game columns  340   1 - 340   5  or specific base game columns  340   1 - 340   5  include at least one feature trigger symbol  320 . For example, the processor  204  may determine that the feature trigger event has occurred if each of the three leftmost base game columns  340   1 - 340   3  includes at least one feature trigger symbol  320 . In some embodiments, the processor  204  may detect the occurrence of a feature trigger event based on other factors such a randomly generated number, amount of coin-in received since the last trigger, a progressive jackpot amount, etc. 
     If a feature trigger event has not occurred, the processor  204  may return to  502  to continue play of the base game. However, if a feature trigger event has occurred, the processor  204  may initiate the feature game. 
     In response to initiating the feature game, the processor  204  at  512  may award prizes identified by the variable components  324  of any feature trigger symbol  320 . In one embodiment, the processor  204  adds such prizes to the feature game win meter  359 . For example, the feature game win meter  359  of  FIG.  3 C  has a value of  325 , which is the sum of the numeric values 100, 75, 100, and 50 provided by the variable components  324  of the displayed feature trigger symbols  320 . 
     In addition to awarding prizes of the feature trigger symbols  320 , the processor  204  at  514  awards a quantity of spins to one or more feature game columns  380   1 - 380   5 . For example, the processor  204 , in one embodiment, may independently award a quantity of spins to each feature game column  380   1 - 380   5  that includes a feature trigger symbol  320 . In other embodiments, the processor  204  may award a quantity of spins to all or a subset of the feature game columns  380   1 - 380   5  regardless of whether the respective feature game column  380   1 - 380   5  includes an instance of the feature trigger symbol  320 . In some embodiments, the processor  204  may award feature game columns  380   1 - 380   5  the same quantity of spins (e.g., three). In other embodiments, the processor  204  may independently award feature game columns  380   1 - 380   5  with different quantities of spins. For example, the processor  204  may award the first feature game column  380   1  with five (5) spins, the second feature game column  380   2  with four (4) spins, the third feature game column  380   3  with three (3) spins, the fourth feature game column  3804  with two (2) spins, and the fifth feature game column  380   5  with one (1) spin. In some embodiments, the quantity of feature spins awarded to feature game columns is based on the quantity of feature trigger symbols in each column. For example, if there is one feature trigger symbol in a column, then a first quantity of feature spins is awarded for that feature game column, and if there are two feature trigger symbols in a column, then a second quantity (preferably larger, but can be smaller) of feature spins is awarded for that feature column. Other combinations of spin award quantities are possible and contemplated. 
     At  514 , the processor  204  may further cause the display device  240  to display spin indicia  396   1 - 396   5  that identify the quantity of spins awarded and thus also identify the quantity of spins remaining for each feature game column  380   1 - 380   5 . For example, as shown in  FIG.  3 C , the processor  204  may update the spin indicia  396   1 ,  396   2 ,  396   3 ,  396   5  of feature game prize tabs  392   1 ,  392   2 ,  392   3 ,  392   5  to indicate that three (3) spins being awarded to the first feature game column  380   1 , the second feature game column  380   2 , the third feature game column  380   3 , and the fifth feature game column  380   5 . In particular, the processor  204  may award such spins due to each of feature game columns  380   1 ,  380   2 ,  380   3 ,  380   5  including an instance of the feature trigger symbol  320 . Conversely, the processor  204  may cause the display device  240  to indicate that no spins were awarded to the fourth feature game column  3804  since the fourth feature game column  3804  lacks a feature trigger symbol  320 . In one embodiment, the processor  204  causes the display device  240  to make such an indication by dimming, ghosting, or blanking game symbols presented in the fourth feature game column  3804  as well as dimming, ghosting, or blanking the feature game prize tab  3924  associated with the fourth feature column  3804 . 
     For each feature game column  380   1 - 380   5  with spins remaining, the processor  204  at  518  may hold any feature trigger symbols  320  in its respective feature game symbols display position  374  and select replacement symbols for each non-feature trigger symbol  328  in the respective column. The processor  204  may further cause the primary game display device  240  to display the replacement symbols at respective feature game symbol display positions  374 . As shown, the processor  204  may cause the display device  240  to present any replacement symbols that are non-feature trigger symbols  328  as a dimmed, ghosted, or blank symbol in order to bring further attention to any replacement symbols that are feature trigger symbols  320 . 
     As explained above, the processor  204  may select the replacement symbols of the feature game outcome  372  by randomly selecting reel stop positions for each feature game reel and its respective feature game reel strip. In one embodiment, the processor  204  selects the replacement symbols using feature game reel strips that include a full set of feature game symbols. In other embodiments, the feature game reel strips may include a reduced set of feature game symbols that take into account the already held feature trigger symbols  320 . In an alternative embodiment, the feature game reel strips may provide an increased set of feature game symbols. For example, a feature trigger symbol  320  may be purchased or otherwise awarded to the feature game reel strips prior to initiating the feature game. 
     At  520 , the processor  204  may decrease the quantity of spins for the feature game column  380   1 - 380   5  and update the spin indicia  396   1 - 396   5  to reflect the decreased quantity of spins remaining for the feature game column  380   1 - 380   5 . In one embodiment, the processor  204  may decrease the quantity of spins by a fixed decrement amount (e.g.  1 ). However, the processor  204  may decrease the quantity of spins remaining by any desired amount. For example, the decrement amount may be dependent upon a particular non-feature trigger symbol  328  selected as a replacement symbol for the respective feature game column  380   1 - 380   5 . 
     The processor  204  at  522  may assign values to variable components  324  of any replacement symbol that is feature trigger symbol  320 . In some embodiments, the processor  204  may assign values to variable components  324  prior to displaying the replacement symbols. The processor  204  may further update the feature game win meter  359  based on the values assigned to the variable components  324 . 
     The processor  204  at  524  may then determines for each feature game column  380   1 - 380   5  whether to award additional spins. In one embodiment, the processor  204  awards additional spins to a feature game column  380   1 - 380   5  in response to a replacement symbol for the respective column being a feature trigger symbol  320 . However, in some embodiments, the processor  204  may elect to award additional spins to a feature game column  380   1 - 380   5  based on other criteria such as, for example, a mystery trigger, a random trigger, a particular non-feature trigger symbol  328 , etc. 
     If additional spins are awarded, then the processor  204  at  524  may increase the quantity of spins for each of the feature game columns  380   1 - 380   5  and update the spin indicia  396   1 - 396   5  to reflect the increased quantity of spins remaining for the feature game column  380   1 - 380   5 . In one embodiment, the processor  204  may increase the quantity of spins by a fixed increment amount (e.g.  1 ). In some embodiments, the processor  204  may increase the quantity of spins by resetting the quantity of spins to its initially award value. For example, if a feature game column  380   1 - 380   5  was initially awarded three (3) spins, the processor  204  may reset the quantity of spins of remaining spins to three (3). In some embodiments, the processor  204  may not increase the quantity of spins, regardless of whether additional feature trigger symbols  320  is shown in any of the feature game columns  380   1 - 380   5 . 
     At  526 , the processor  204  determines for each feature game column  380   1 - 380   5  whether to award any column prizes. In one embodiment, the processor  204  may determine that a column prize is to be awarded when its respective feature game column  380   1 - 380   5  includes at least a threshold number of the feature trigger symbol  320 . For example, the processor  204  may determine to award the column prize when its feature game column  380   1 - 380   5  includes a number of feature trigger symbols  320  equal to the number of feature game symbol display positions  374  in the feature game column  380   1 - 380   5 . In other embodiments, the threshold number may be less than the number of feature game symbol display positions  374 . For example, the processor  204  may determine to award a column prize when at least three (3) of four (4) symbol display positions  374  in a feature game column  380   1 - 380   5  includes instances of the feature trigger symbol  320 . In addition, the processor  204  may determine to award a column prize based on the non-feature trigger symbols  328  selected as replacement symbols. For example, the processor  204  may determine to award a column prize in response to a particular non-feature trigger symbol being selected for its respective feature game column  380   1 - 380   5 . 
     For any awarded column prizes, the processor  204  at  526  may update feature game win meter  359 . In particular, the processor  204  may add a credit value of any awarded column prizes to a currently depicted credit value for the feature game win meter  359 . The processor  204  further sets the remaining spins to zero (0) for any feature game column  380   1 - 380   5  that resulted in an award of its column prize. 
     At  528 , the processor  204  determines, based on the quantity of spins for each feature game column  380   1 - 380   5 , whether a feature game column  380   1 - 380   5  has no remaining spins. If a column has no remaining spins, the processor  204  at  528  may determine that the feature game is over or completed for that particular feature game column  380   1 - 380   5  and may reflect such status to player. For example, the processor  204  in one embodiment causes the display device  240  to present a spin indicia  396   1 - 396   5  of “completed” for each feature game column  380   1 - 380   5  that has no remaining spins. 
     If any feature game column  380   1 - 380   5  has spins remaining at  530 , the processor  204  may return to  518  in order to further spin reels of the respective feature game column  380   1 - 380   5 . On the other hand, once all feature game columns  380   1 - 380   5  have no spins remaining, the feature game ends. In response to the feature game ending, the processor  204  may transfer credits of the feature game win meter  359  and the base game win meter  356  to the credit balance meter  352 . After updating the meters, the processor  204  may return to  502  after any prizes are paid at step  532 . 
     Referring now to  FIGS.  3 A- 3 G , an example play through of the base game and the feature game are described.  FIG.  3 A  shows an example base game screen  300  with a base game outcome  332  that includes both feature trigger symbols  320  and non-feature trigger symbols  328 . The base game screen  300  further depicts current prize values  314   1 - 314   5  and base game prize tabs  342   1 - 342   5  that identifies column prize values for each base game column  340   1 - 340   5 . As further shown, the base game outcome  300  includes a winning combination of four (4) “10” symbols along payline  302  as well as four (4) feature trigger symbols  320 . In the embodiment depicted, three (3) feature trigger symbols  320  is sufficient to trigger the feature game. 
       FIG.  3 B  depicts triggering of the feature game as a result of the base game outcome of  FIG.  3 A . As shown, the non-feature trigger symbols  328  have been dimmed or ghosted thus further highlighting the feature trigger symbols  320 . The base game win meter  356  further shows that 35 credits were awarded due to winning combinations of non-feature trigger symbols  328  in the base game outcome  332  such as, for example, the four (4) “10” symbols along payline  302 . 
     The feature game screen  360  of  FIG.  3 C  depicts an initial state of the feature game resulting from the base game outcome of  FIG.  3 A . In particular, base game prize tabs  342   1 ,  342   2 ,  342   3 ,  342   5  of  FIG.  3 A  have transitioned into feature game prize tabs  392   1 ,  392   2 ,  392   3 ,  392   5  to show that each of feature game columns  380   1 ,  380   2 ,  380   3 ,  380   5  has been awarded three (3) spins due to the presence of a feature trigger symbol in each of such columns. Moreover, the feature game prize tab  3924  is dimmed or ghosted to show that the fourth feature game column  3084  was not awarded spins and therefore will not be part of the current feature game. The feature game win meter  359  further depicts 325 credits, which is the sum of the variable components  324  of the four feature trigger symbols  320 . 
       FIG.  3 D  depicts the feature game screen  360  after each of feature game columns  380   1 ,  380   2 ,  380   3 ,  380   5  received replacement symbols as a result of a single spin of such columns. Of note, the spin indicia  396   1 ,  396   5  for the first feature game column  380   1  and the fifth feature game column  380   5  have been decreased by one (1) to two (2) spins to reflect that one of the initially award three (3) spins has been used for those columns. Conversely, the spin indicia  396   2 ,  396   3  for the second feature game column  380   2  and the third feature game column  380   3  remain at three (3) spins. Like the feature game columns  380   1 ,  380   5 , the spins awarded to feature game columns  380   2 ,  380   3  were decreased by one (1) to two (2) spins to reflect that one of the initially award three (3) spins has been used for those columns, but were subsequently reset to their initial awarded spins of three (3) due to each feature game column  380   2 ,  380   3  receiving at least one feature trigger symbol  320  as a replacement symbol. The feature game win meter  359  has been increased to 575 credits to reflect the credit values of the newly presented feature trigger symbols  320  in feature game columns  380   2 ,  380   3 . 
       FIG.  3 E  depicts the feature game screen  360  after another spin of each of feature game columns  380   1 ,  380   2 ,  380   3 ,  380   5 . Of note, the spin indicia  396   1 - 396   3  for feature game columns  380   1 - 380   3  have been decreased by one (1) to reflect that another spin has been used for those columns. Conversely, the spin indicia  396   5  for the fifth feature game column  380   5  has been reset to its initial awarded spins of three (3) due to receiving at least one feature trigger symbol  320  as a replacement symbol. The feature game win meter  359  has been increased to 1125 credits to reflect the credit values of the newly presented feature trigger symbols  320  in the first feature game column  380   5 . 
       FIG.  3 F  depicts the feature game screen  360  after two more spins of each feature game column  380   1 ,  380   2 ,  380   3 ,  380   5 . Of note, the spin indicia  396   2 ,  396   3  for the second feature game column  380   2  and the third feature game column  380   3  indicate that the feature game is complete for those columns. Namely, feature game columns  380   2 ,  380   3  failed to receive an additional feature trigger symbol  320  during those two additional spins. As a result, the second feature game column  380   2  and the third feature game column  3083  have used all of their awarded spins. Similarly, the fifth feature game column  380   5  failed to receive a feature trigger symbol during those two additional spins. But, as shown by the feature game prize tab  392   5 , the fifth feature game column  380   5  still has one remaining spin. Conversely, the first feature game column  380   1  received a feature trigger symbol  320  as a result of the first of the two additional spins. As a result, its quantity of spins was reset to three (3) spins, prior to the second spin of the two additional spins. Accordingly, the first feature game column  380   1  still has two remaining spins as reflected by the first spin indicia  396   1 . The feature game win meter  359  has 1200 credits, which is the sum of all of the variable components  324  of the feature trigger symbols  320  in feature game columns  380   1 - 380   5 . 
     Finally,  FIG.  3 G  depicts the feature game screen  360  after two successful spins of the first feature game column  380   1  and a single unsuccessful spin of the fifth feature game column  380   5 . The single unsuccessful spin of the fifth feature game column  380   5  used the last spin awarded to the column. As a result, the feature game prize tab  392   5  indicates the fifth feature game column  380   5  has completed the feature game. As further shown, the feature game prize tabs  392   2 ,  392   3 ,  392   5  of the completed feature game columns  380   2 ,  380   3 ,  380   5  may be dimmed or ghosted to bring further attention to the columns that are still active. The two successful spins of the first feature game column  380   1  results in there being four (4) feature trigger symbols  320  in the first feature game column  380   1 . In one embodiment, the processor  204  awards the associated column prize in response to four (4) feature trigger symbols  320  in the respective column. As shown, the first feature game prize tab  392   1  indicates a winner of the associated column prize, which is the mini prize value  314   1  of $10.00. As shown by the monetary denomination indicator  358 , the game denomination is 1¢. Thus, the $10.00 mini prize value corresponds to 1000 credits. The feature game win meter  359  is shown with 2350 credits, which is the sum of the award mini prize value  314   1  (1000 credits) and all the credit values depicted by the variable components  324  of the feature trigger symbols  320  displayed in feature game columns  380   1 - 380   5 . 
     In various embodiments, the (a) quantity of feature trigger symbols per symbol column required to trigger the feature game, (b) quantity of feature trigger symbols in a symbol column required to award the column prize, (c) numeric value of the variable component  324 , (d) prize value of the one or more prize indicia may be (i) predetermined, (ii) randomly determined, and/or (iii) based at least in part on one or more of the following (1) wager amount, (2) amount of money wagered over a player session, and/or (3) a player&#39;s player account status, etc. 
     Although the flowchart of  FIG.  5    shows a specific order of execution, it is understood that the order of execution may differ from that which is depicted. For example, the order of execution of two or more blocks may be scrambled relative to the order shown. Also, two or more blocks shown in succession in  FIG.  5    may be executed concurrently or with partial concurrency. Further, in some embodiments, one or more of the blocks shown in  FIG.  5    may be skipped or omitted. In addition, any number of counters, state variables, warning semaphores, or messages might be added to the logical flow described herein, for purposes of enhanced utility, accounting, performance measurement, or providing troubleshooting aids, etc. It is understood that all such variations are within the scope of the present disclosure. 
     While the invention has been described with respect to the figures, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention. Any variation and derivation from the above description and figures are included in the scope of the present invention as defined by the claims.