Patent Publication Number: US-2003232644-A1

Title: Gaming machine and method of controlling the same

Description:
BACKGROUND OF THE INVENTION  
       [0001] The invention relates to a gaming machine which displays temporary symbols and changes the thus-displayed temporary symbols into substantial symbols associated therewith when a predetermined requirement is satisfied, as well as a method of controlling the gaming machine.  
       [0002] For example, U.S. Pat. No. 5,152,529 describes a gaming machine equipped with inner reels and outer reels. In this gaming machine, when “BLANK” is stationarily displayed on the outer reel, the inner reel is further spun, to thereby stationarily display a specific symbol through the blank. Specifically, the gaming machine performs two independent lottery operations; that is, lottery operation for the outer reel and lottery operation for the inner reel.  
       [0003] However, the technique for displaying symbols using the outer and inner reels has become well known to players. Therefore, a new technique for displaying symbols which arouses the players&#39; interests is desired. Particularly, many types of gaming machines using video reels have recently been known. Since the video reels can effect a variety of display operations, a suitable technique for the video reels to display symbols has been expected.  
       SUMMARY OF THE INVENTION  
       [0004] It is therefore an object of the invention to provide a gaming machine which can enhance a player&#39;s expectation and arouse the player&#39;s interest, as well as a method of controlling such a gaming machine.  
       [0005] In order to achieve the above object, according to the invention, there is provided a gaming machine, comprising:  
       [0006] a random number selector, which selects at least one random number;  
       [0007] a display, which displays at least one of plural symbols in accordance with the selected random number, the plural symbols including at least one first symbol which is associated with a second symbol in a one-to-one correspondence; and  
       [0008] a replacement controller, which selects the first symbol with the second symbol when a predetermined requirement is satisfied under a condition that the first symbol is displayed in the display.  
       [0009] In such a configuration, the player cannot determine the nature of the second symbol by only the appearance of the first symbol. Accordingly, when the first symbol has been displayed, the player will have a large expectation for the nature of the second symbol which will appear in association with the first symbol. Moreover, emergence of a second symbol serves as a chance for the player gaining a profit. For example, emergence of the second symbol may be used as a requirement for activating a bonus game or for offering a large amount of payment. As a result, when the first symbol has appeared, the player&#39;s interest can be aroused in relation to whether or not the first symbol transforms to the second symbol or in relation to the nature of the second symbol which will appear in association with appearance of the first symbol.  
       [0010] Preferably, the plural symbols includes plural kinds of first symbols appearances of which are different from each other.  
       [0011] In such a configuration, even when the first symbol is displayed, the player encounters difficulty in predicting the nature of the second symbol. As a result, when the first symbol has appeared, the player&#39;s expectation can be enhanced.  
       [0012] Preferably, the display first displays the plural symbols variably, and then displays at least one of the plural symbols stationarily in accordance with the selected random number.  
       [0013] In such a configuration, the invention can be applied to a gaming machine equipped with physical reels and video reels.  
       [0014] Here, it is preferable that the predetermined requirement is that a plurality of first symbols are stationarily displayed in the display.  
       [0015] In such a configuration, when one of the first symbol is first displayed, the player&#39;s expectation can be enhanced.  
       [0016] It is also preferable that the plural symbols includes at least one third symbol, and the predetermined requirement is that the first symbol and the third symbol are stationarily displayed in the display.  
       [0017] In such a configuration, when the first symbol is displayed, the player&#39;s expectation for display of the third symbol can be enhanced. When the first symbol and the third symbol have been displayed, the first symbol transforms to the second symbol, the player&#39;s expectation for appearance of the second symbol can be enhanced.  
       [0018] Here, it is preferable that the predetermined requirement is that the first symbol and a plurality of third symbols are stationarily displayed in the display.  
       [0019] In such a configuration, when the first symbol is displayed, the player&#39;s expectation for display of the plurality of third symbols can be enhanced. When the first symbol and the plurality of third symbols have been displayed, the first symbol transforms to the second symbol, and the player&#39;s expectation for appearance of a second symbol can be enhanced.  
       [0020] It is also preferable that the predetermined requirement is that a predetermined time period elapses from when the first symbol is stationarily displayed in the display.  
       [0021] In such a configuration, when the first symbol is displayed, the player&#39;s expectation can be enhanced.  
       [0022] It is also preferable that the gaming machine further comprises a cluster in which the plural symbols are arranged according to a predetermined order with regard to the first symbol. The display comprises a plurality of display areas, each operable to display the plural symbols arranged in the cluster.  
       [0023] In such a configuration, since the clusters are identical with each other in terms of a layout pattern in connection with the first symbol, the player encounters difficulty in predicting appearance of a second symbol associated with the first symbol on the basis of the symbols appearing in the vicinity of the first symbol.  
       [0024] It is alternatively preferable that the gaming machine further comprises a plurality of clusters in which the plural symbols are arranged according to different orders with regard to the first symbol. The display comprises a plurality of display areas, each operable to display the plural symbols arranged in one of the clusters.  
       [0025] In such a configuration, when a certain first symbol has been stationarily displayed, since the pattern into which symbols are to be arranged around the first symbol differs from one cluster to another cluster, the player becomes able to predict a second symbol associated with the first symbol by the symbols located in the vicinity of the first symbol. As a result, a predictive function (declaring occurrence of a win) can be realized, thereby arousing the player&#39;s interest.  
       [0026] According to the invention, there is also provided a method of controlling a gaming machine, comprising steps of:  
       [0027] selecting at least one random number;  
       [0028] displaying, in a display, at least one of plural symbols in accordance with the selected random number, the plural symbols including at least one first symbol which is associated with a second symbol in a one-to-one correspondence; and  
       [0029] converting the first symbol into the second symbol when a predetermined requirement is satisfied under a condition that the first symbol is displayed in the display.  
       [0030] Preferably, the plural symbols are variably displayed first, and then at least one of the plural symbols is displayed stationarily in accordance with the selected random number.  
       [0031] Here, it is preferable that the predetermined requirement is that a plurality of first symbols are stationarily displayed in the display.  
       [0032] It is also preferable that the plural symbols includes at least one third symbol, and the predetermined requirement is that the first symbol and the third symbol are stationarily displayed in the display.  
       [0033] Here, it is preferable that the predetermined requirement is that the first symbol and a plurality of third symbols are stationarily displayed in the display.  
       [0034] It is also preferable that the predetermined requirement is that a predetermined time period elapses from when the first symbol is stationarily displayed in the display. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0035] The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein:  
     [0036]FIG. 1 is a perspective view showing the appearance of a gaming machine according to an embodiment of the invention;  
     [0037]FIG. 2 is a block diagram showing the electrical configuration of the gaming machine;  
     [0038]FIGS. 3 and 4 are flowcharts showing operation performed in the gaming machine; and  
     [0039]FIGS. 5 through 8 are views showing example displays in a symbol display of the gaming machine.  
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0040] A gaming machine according to an embodiment of the invention will be described hereinbelow. On the basis of a result of internal lottery operation (random number selection), the gaming machine of the embodiment displays a plurality of types of symbols including temporary symbols associated with substantial symbols in a one-to-one correspondence. Here, the substantial symbols have specific designs and characteristics capable of offering a specific payment to a player when appearing on a pay line. On the other hand, the temporary symbols have the function of masking the substantial symbols. The temporary symbols are associated with the substantial symbols in a one-to-one correspondence in advance. When a predetermined requirement has been satisfied, the temporary symbol transforms to the substantial symbol. At this time, the nature of the substantial symbol appears for the first time. The predetermined requirement of the embodiment is that a trigger symbol must appear simultaneously with display of the temporary symbol. Specifically, the trigger symbol has the function of transforming the temporary symbol to the substantial symbol.  
     [0041] As shown in FIG. 5, a symbol  62 , which shows a submarine pier and appears in a block of a fifth reel  75 , is taken as a temporary symbol in the embodiment. Further, as shown in FIG. 5, a symbol  60 , which shows a submarine  61  and appears in a block of a first reel  71 , is taken as a trigger symbol. As shown in FIG. 7, a symbol  70 , which shows a treasure chest and appears in a block of the fifth reel  75 , is taken as a substantial symbol. Moreover, as shown in FIG. 8, a symbol  80 , which shows ruins and appears in the block of the fifth reel  75 , is taken as a substantial symbol. The substantial symbol  70  is given the function of activating a “treasure chest game” when appeared on a pay line. The substantial symbol  80  is given the function of activating a “ruins game” when appeared on the pay line. These substantial symbols are usually displayed as the temporary symbol  62  shown in FIG. 5 so that the player does not know the nature of the symbol.  
     [0042] When the temporary symbol  62  is displayed along with the trigger symbol  60 , the thus-displayed temporary symbol  62  is transformed into a substantial symbol associated therewith. Here, a plurality of types of symbols, including the temporary symbol  62 , may be variably displayed. On the basis of a result of internal lottery (random number selection), the variably-displayed symbol may be stationarily displayed, thereby enabling application of the invention to a gaming machine having a physical reel and a video reel. As a result, the player&#39;s expectation for a symbol to be stationarily displayed can be enhanced. Further, the player&#39;s interest can be aroused in relation to whether or not an appearing temporary symbol is transformed to a substantial symbol and in relation to the nature of a substantial symbol which will appear.  
     [0043] The invention can be applied to all gaming machines capable of displaying symbols. The invention will now be described by taking, as an example, a gaming machine which can variably display a plurality of types of symbols in the direction of a column (or in the direction of a row) and stationarily display the variably-displayed symbol on the basis of a result of internal lottery operation (random number selection). Mechanical drums (reels) may be used for a section of the machine where symbols are to be variably displayed. Alternatively, video reels which variably display symbols as images on a liquid-crystal screen or the like may also be employed. The invention can also be applied to a skilled-stop type gaming machine which enables the player to determine timings at which the drums (reels) are to be stopped and a sequence in which the drums are to be stopped by actuation of stop buttons at the player&#39;s will, as in the case of a slot machine. The invention can also be applied to a gaming machine in which reels automatically, sequentially come to a halt regardless of the player&#39;s will, as in the case of a slot machine. The embodiment will be described by taking tokens as gaming values. However, the invention is not limited to the tokens; all mediums capable of offering gaming values may be adopted.  
     [0044] As shown in FIG. 1, a gaming machine  1  is constituted of a housing  2 , and a front panel  3  reclosably attached to the front of the housing  2 . Attached to the back of the front panel  3  is a symbol display  7  which is formed from a liquid-crystal panel or cathode ray tube (CRT) and displays symbols in, e.g., five lines. The embodiment adopts a video reel system, and five reels are displayed on the symbol display  7  by execution of a program.  
     [0045] As shown in FIG. 5, the symbol display  7  has five reels which variably and stationarily display symbols in the direction of a column (i.e., the vertical direction of the gaming machine). Specifically, the symbol display  7  has a first reel  71 , a second reel  72 , a third reel  73 , a fourth reel  74 , and a fifth reel  75 . Each reel can variably or stationarily display various symbols.  
     [0046] The symbol display  7  includes a plurality of temporary symbols of identical appearance. Specifically, the temporary symbols each have the same submarine pier. The temporary symbols are associated with different substantial symbols in a one-to-one correspondence. In the symbol display  7 , there are formed a plurality of clusters which are identical with each other in terms of a layout pattern into which symbols are to be arranged, with each temporary symbol being taken as a center. Here, the cluster is a group formed from a plurality of symbols. As mentioned above, the plurality of types of symbols are variably displayed in the direction of a column. On the basis of a result of internal lottery, the variably-displayed symbols are stationarily displayed. Since the clusters are identical with each other in terms of a layout pattern into which, when a certain temporary symbol has been displayed, the player encounters difficulty in predicting appearance of a substantial symbol associated with the temporary symbol on the basis of the symbols appearing in the vicinity of the temporary symbol.  
     [0047] For example, there is provided the case of a reel which variably displays symbols in the direction of a column (i.e., the vertical direction of the gaming machine) and three symbols; one in an upper row, one in a middle row, and the other in a lower row. In this case, the respective clusters assume the same layout pattern; that is, two symbols appearing at a position above a temporary symbol, and two other symbols appearing at a position below the temporary symbol. More specifically, under the assumption that symbols are represented as capital letters, the layout pattern of symbols in each cluster is defined as, e.g., “B, C, A, D, E” from the upper side to lower side of the reel. As a result, when temporary symbols are displayed in the upper row, “A, D, E” appear in each cluster. When temporary symbols are displayed in the middle row, “C, A, D” appear in each cluster. When temporary symbols are displayed in the lower row, “B, C, A” appear in each cluster. In this way, symbols, including the temporary symbols, are arranged in the same pattern as are those belonging to the cluster. Since the layout patterns are identical for all the cluster, difficulty is posed on the player in predicting a substantial symbol to which a displayed temporary symbol is transformed, thereby enhancing the player&#39;s expectation.  
     [0048] A token insertion slot  10  and a token return button  10   a  to be used for returning tokens when inserted coins have caused clogging are provided on the front of the housing  2 . A start lever  11  is a lever for starting rotational display (variable display) of the symbol display  7 .  
     [0049] The gaming machine  1  starts a game by the player specifying a valid pay line (i.e., a payout line). There player can set a plurality of pay lines, e.g., a horizontal center line, horizontal upper and lower lines, and sloped lines. BET operation is performed by insertion of a token into the token insertion slot  10  to be described later or by betting some of the tokens reserved by a reserved token insert button  21 . The BET operation can also be performed by combined use of these BET operations.  
     [0050] When the pay line has been specified through the player&#39;s BET operation and the player has actuated the start lever  11 , the symbol display  7  variably displays symbols. When a predetermined period of time has lapsed, the symbol display  7  sequentially stops the variably-displayed symbols. The symbols are stopped in sequence from left to right while the player faces the symbol display  7 . At the time of stoppage of the symbols, the symbols are stopped at a time interval of, e.g., 0.5 seconds. When a combination of predetermined symbols is displayed along any of the pay lines as a result of the symbols having come to a halt, a win associated with the combination of symbols is provided.  
     [0051] A token payout port  15  and a token receiver  16  are provided at a lower portion of the front panel  3 . A game presentation indicator  17  which is driven for providing game presentation is provided at an upper portion of the front panel  3 . The game presentation indicator  17  is formed from, e.g., an LCD (liquid-crystal display) or lamps of various types. The embodiment shows an example where an LCD is adopted. A bonus game indicator  18  is provided at an upper portion of the front panel  3 . The bonus game indicator  18  is formed from an LED (light-emitting diode). The bonus game indicator  18  displays winning or acquisition of a bonus prize which offers a high gaming value to the player, game presentations, and occurrence of an error. Speakers  19  produce sound guidance, music, sound effects, or the like. When a win has arisen for a bonus prize, a game is developed in a manner advantageous to the player; for example, a game is developed such that the probability of occurrence of a win becomes one-third.  
     [0052] A plurality of lamps  20  provided on the front panel  3  effect display of a game, such as display of a validated pay line or display of occurrence of a win, in accordance with the number of inserted tokens (or the amount of a betted credit) through illumination, extinction, or blinking. The reserved token insert button  21  is for using only a predetermined number of tokens reserved in an unillustrated token storage. A reserved token infusion button  22  is for using a maximum specified number of tokens reserved in the unillustrated token storage. A reserved token count display  23  displays the number of tokens stored in the unillustrated token storage. A win count display  24  displays the number of times a win has arisen or the number of remaining games at the time of occurrence of a win for a bonus prize. A payout token count display  25  displays the number of tokens to be paid. The reserved token count display  23 , the win count display  24 , and the payout token count display  25  are each formed from, e.g., an LED. A settlement button  26  effects settlement of reserved tokens. A locking device  27  locks a door when turned in a proper direction. The type and manufacturer of the gaming machine  1  are provided on a label  28 .  
     [0053]FIG. 2 is a block diagram showing an electrical configuration of the gaming machine  1  of the embodiment. As shown in FIG. 2, the gaming machine  1  is electrically made up of a main board A and a sub-board B. The main board A has a CPU  30 , ROM  31 , and RAM  32  and performs control operation in accordance with a preset program. In addition to storing a control program to be used for controlling operation of the gaming machine  1 , the ROM  31  stores a prize group sampling table to be used for determining a prize group in advance (through internal lottery). The CPU  30 , the ROM  31 , and the RAM  32  constitute a symbol selector.  
     [0054] The CPU  33  is connected to a clock generator  33  for generating a reference clock pulse and to a random number generator  34  for generating a given random number. The CPU  30  and the random number generator  34  constitute a random number selector. By way of an output port  35 , a control signal sent from the CPU  30  is output to a token payout device  36 , which pays tokens, and to a symbol display controller  37 , which controls the symbol display  7 .  
     [0055] A signal output from a token discriminator  38  for determining whether or not a token is genuine; a signal output from a payout token counter  40  for counting the number of tokens to be paid; and a signal output from a start lever  41  which starts spinning of reels are input to the CPU  30  by way of an input port  43 . The signal output from the CPU  30  is output to the sub-board B by way of a data transmitter  46  under control of a transmission timing controller  45  for controlling a timing at which a signal is to be transmitted to the sub-board B.  
     [0056] In the sub-board B, the signal output from the data transmitter  46  is input to a data receiver  47 . The signal input to the data receiver  47  is processed by a CPU  48 . The CPU  48  is connected to a clock generator  49  for generating a reference clock pulse, ROM  50  having various programs and image data recorded therein, and RAM  51 . Data pertaining to images are output from the CPU  48  to a liquid-crystal display  53  via a display processor  52 , which performs image processing operation. The liquid-crystal display  53  displays characters, a still image, a moving image, and the like.  
     [0057] Data pertaining to sound are output from the CPU  48  to an amplifier  56  via a sound LSI  54 , which performs sound processing operation. The sound LSI  54  extracts required sound data from sound ROM  55 , thereby processing sound data. Sound data which have been subjected to processing, such as amplification, performed by the amplifier  56  are output to a speaker  58  via a sound controller  57 .  
     [0058] Operation of the gaming machine of the embodiment having the foregoing configuration will now be described with reference to FIGS. 3 through 8. In FIGS. 5 through 8, symbols other than a temporary symbol  62 , a trigger symbol  60  and substantial symbols  70 ,  80  are represented as blanks, and specific display of the symbols is omitted.  
     [0059] First, an ordinary game start operation is performed (step S 1 ). Here, as mentioned above, one or more pay lines are specified by the BET operation performed by the player, and the start lever  11  is actuated. Next, random numbers to be used for determining stop numbers of the first through fifth reel strips are acquired (step S 2 ). A determination is made as to whether or not a win has arisen for an ordinary game (step S 3 ). Then, spinning of the first through fifth reels is started (step S 4 ).  
     [0060] Spinning of the first through fifth reels is sequentially stopped (step S 5 ). Here, the reels are sequentially stopped from the first reel to the fifth reel at predetermined time intervals. Time intervals can be set to a value of, e.g., 0.5 seconds. As shown in FIG. 4, a determination is made as to whether or not a trigger symbol  60  showing a submarine  61  is displayed on the first reel (step S 6 ). Here, as shown in FIG. 5, the trigger symbol  60  is displayed on the first reel  71 . Next, a determination is made as to whether or not the symbol showing a submarine pier is displayed in block of the fifth reel  75  (step S 7 ). Here, as shown in FIG. 5, the temporary symbol  62  showing a submarine pier is displayed on in the block of the fifth reel  75 . Since the trigger symbol  60  and the temporary symbol  62  have been displayed on the symbol display  7 , a requirement for transforming the temporary symbol  62  to a substantial symbol is satisfied.  
     [0061] Next, as shown in FIG. 6, the submarine drawn on the trigger symbol  60  appearing in the block of the first reel  71  starts moving toward the temporary symbol  62  appearing in the block of the fifth reel  75  (step S 8 ). At this time, in order to enhance the effect of presentations, a pulse sound or the like which is produced when the submarine  61  travels across the ocean floor may be emitted. When the submarine  61  has arrived at the temporary symbol  62  showing the submarine pier, the temporary symbol  62  intensively illuminates, whereupon background scenery for the submarine pier of the temporary symbol  62  appears. A determination is then made as to what is in the background scenery behind the temporary symbol  62  on the fifth reel  75  of the submarine pier (step S 9 ).  
     [0062] As shown in FIG. 7, when a substantial symbol  70  having a treasure chest drawn is displayed on the fifth reel  75 , a treasure chest game is activated (step S 10 ). In contrast, as shown in FIG. 8, if a substantial symbol showing ruins is displayed in the block on the fifth reel  75 , a ruins game is activated (step S 11 ). Here, both the treasure chest game and the ruins game are bonus games for offering profits to the player. As a result, when the temporary symbol has appeared, the player can feel premonition of a bonus game.  
     [0063] As mentioned above, the temporary symbol and the substantial symbol are associated with each other in a one-to-one correspondence. If the requirement is not satisfied, the temporary symbol does not transform to the substantial symbol. The requirement is that, in the embodiment, the temporary symbol  62  and the trigger symbol  60  must be displayed. When the temporary symbol  62  and the trigger symbol  60  have been displayed, the temporary symbol  62  transforms to a corresponding substantial symbol ( 70  or  80 ). At this time, the associated substantial symbol becomes evident to the player. Thereby, when the temporary symbol  62  is displayed, the player&#39;s expectation for display of the trigger symbol  60  can be enhanced. When the temporary symbol  62  and the trigger symbol  60  have been displayed, the temporary symbol  62  transforms to the substantial symbol ( 70  or  80 ), and the player&#39;s expectation for appearance of a substantial symbol can be enhanced.  
     [0064] In step S 6 , when the trigger symbol  60  showing a submarine is not displayed in the block of the first reel  71  and when the temporary symbol  62  showing a submarine pier is not displayed in block of the fifth reel  75 , processing proceeds to step S 12 .  
     [0065] Finally, game result processing is performed (step S 12 ), and processing returns to a game start standby state.  
     [0066] In the description, the trigger symbol  60  appears in the first reel  71  and the temporary symbol  62  appears in the fifth reel  75 . However, the reel in which each of the trigger symbol  60  and the temporary symbol  62  appears is not limited to the above unless they appear in the same reel.  
     [0067] In the description, one type of symbol; that is, a symbol showing a submarine pier, is used for the temporary symbol  62 . However, a plurality of types of temporary symbols having different appearances may be used. In addition to the symbol showing a submarine pier, a symbol showing a door may be employed. As a result, any of these temporary symbols is displayed, the player encounters difficulty in predicting correspondence between the temporary symbol and a substantial symbol. Thus, when the temporary symbol is displayed, the player&#39;s expectation can be enhanced.  
     [0068] Further, display of a plurality of temporary symbols may be employed as the requirement. Specifically, the gaming machine is configured such that temporary symbols can transform to substantial symbols when a plurality of temporary symbols, each showing a submarine pier, are simultaneously displayed. The gaming machine is also configured such that, when the temporary symbol showing a submarine pier and the symbol showing a door are simultaneously displayed, the temporary symbols can transform to substantial symbols.  
     [0069] In this way, when the plurality of temporary symbols are displayed, each of the temporary symbols transforms to an associated substantial symbol. At this time, the nature of the substantial symbols associated with the temporary symbols becomes evident to the player for the first time, thereby enhancing the player&#39;s expectation aroused when the temporary symbol is displayed.  
     [0070] A plurality of trigger symbols may be provided, and display of a plurality of trigger symbols along with a temporary symbol may be set as the requirement. For example, a symbol showing a door is taken as a temporary symbol; and a symbol showing a key and a symbol showing a submarine are taken as trigger symbols. When the temporary symbol showing a door, the trigger symbol showing a key, and the trigger symbol showing a submarine are displayed simultaneously, presentation is offered such that the door of the temporary symbol is opened and the temporary symbol is transformed into the substantial symbol.  
     [0071] As mentioned above, when the temporary symbol and the plurality of trigger symbols are displayed, the temporary symbol transforms to an associated substantial symbol. At this time, the substantial symbol associated with the trigger symbols becomes evident. As a result, when the temporary symbol has been displayed, the player&#39;s expectation for emergence of a plurality of trigger symbols can be enhanced. When the temporary symbol is displayed in conjunction with a plurality of trigger symbols, the temporary symbol transforms to a substantial symbol. Therefore, the player&#39;s expectation for emergence of a substantial symbol can be enhanced.  
     [0072] Moreover, lapse of a predetermined period of time since a temporary symbol was displayed may also be determined as the requirement. When a predetermined period of time has lapsed since a temporary symbol was displayed, the temporary symbol transforms to an associated substantial symbol. At this time, the nature of the substantial symbol becomes obvious to the player for the first time. As a result, when the temporary symbol has been displayed, the player&#39;s expectation for emergence of a substantial symbol can be enhanced.  
     [0073] Moreover, a plurality of clusters which differ in layout pattern such that symbols are arranged around each temporary symbol may be adopted. As mentioned above, the cluster corresponds to a group formed from a plurality of symbols; that is, a group of symbols. A plurality of types of symbols are variably displayed in the direction of a column, whereas the variably-displayed symbols are stationarily displayed on the basis of result of internal lottery operation. Since the pattern into which symbols are to be arranged around the temporary symbol differs from one cluster to another cluster, the player becomes able to predict a substantial symbol associated with the temporary symbol by the symbols located in the vicinity of the temporary symbol.  
     [0074] For instance, in the case of the reels which variably display symbols in the direction of a column (i.e., the vertical direction of the gaming machine), there is shown a case where three symbols are displayed; one in an upper row, one in a middle row, and the other in a lower row. In this case, in each cluster, two symbols located in an upward direction with reference to the temporary symbol differ in layout pattern from two symbols located in a downward direction with reference to the same. Specifically, under the assumption that symbols are represented by capital letters and that a symbol showing a submarine pier to be taken as a temporary symbol is taken as symbol A, symbols in a certain cluster are arranged from an upper side to lower side of the reel; for example, “B, C, A, D, E.” In other clusters, symbols may be arranged such as “D, E, A, B, C” or “F, G, A, H, I.” 
     [0075] Therefore, we assume that symbols of a certain cluster are arranged into a pattern of “B, C, A, D, E” and that the substantial symbol associated with the temporary symbol A is a symbol for starting a bonus game. When the temporary symbol A is displayed in, e.g., an upper row and when symbol “D” has come to the middle row and symbol “E” has come to the lower row, the player can predict that the temporary symbol A is a substantial symbol for activating a bonus game. As a result, a predictive function (declaring occurrence of a win) can be realized, thereby arousing the player&#39;s interest.  
     [0076] The invention can be applied not only to the gaming machine using the foregoing reels, but also to a gaming machine by which the player plays card games, such as poker or black jack, while images of cards are being displayed. For example, the invention can also be applied to a gaming machine which offers a bingo game.  
     [0077] The previously-described characteristic operations of the gaming machine of the invention are performed by causing a computer to execute a control program.  
     [0078] The program is available while being recorded on a recording medium, such as a CD-ROM or a DVD. Further, such a program is also available by receiving a signal transmitted from a computer serving also as a transmitter, via a communication network constituted of a transmission medium, such as a public telephone line, a private telephone line, a cable television line, or a radio communication line. The signal is computer data embodied in the form of a predetermined carrier wave including a program. At the time of transmission, the only requirement is to transmit at least a portion of the program over the transmission medium. Namely, there is no necessity for all the data constituting the program to exist in the transmission medium at a single time. A method for transmitting the program from the computer includes a situation in which data constituting the program are consecutively transmitted and a situation in which the data are transmitted intermittently.  
     [0079] Although the present invention has been shown and described with reference to specific preferred embodiments, various changes and modifications will be apparent to those skilled in the art from the teachings herein. Such changes and modifications as are obvious are deemed to come within the spirit, scope and contemplation of the invention as defined in the appended claims.