AU2013276990A1 - A gaming system and a method of gaming - Google Patents

Abstract

Abstract A bonus game controller is disclosed for use with a plurality of gaming machines in networked relationship 5 with the bonus game controller. The bonus game controller comprises a trigger determiner arranged to determine whether a bonus trigger signal has occurred at a gaming device. The bonus game controller is arranged to implement a first bonus game when a bonus trigger signal 10 occurs at a gaming device, and also comprises a bonus prize allocator arranged to allocate a bonus prize to the gaming device based on an outcome of the first bonus game and based on one or more respective outcomes of at least one other subsequent bonus game implemented within a 15 qualification period. A gaming system including a plurality of gaming devices and a game controller is also disclosed. A corresponding method is also disclosed. 4990332_1 (GHMatters) P76390.AU.2

Description

1 A GAMING SYSTEM AND A METHOD OF GAMING Field of the Invention 5 The present invention relates to a gaming system, to a bonus game controller and to a method of gaming. Background of the Invention 10 It is known to provide a gaming system which comprises a plurality of player operable gaming devices connected together in a network and a bonus game controller which communicates with the gaming devices through the network and implements a bonus game when a bonus trigger is 15 received from a gaming device. Typically, the bonus game controller includes a relatively large screen which is disposed at a location such that players of the gaming devices are able to view the bonus 20 game currently being played by one of the players. However, with this type of bonus game arrangement, there is little interest in the bonus game by players of the gaming devices not involved in the bonus game. 25 Summary of the Invention In accordance with a first aspect of the present invention, there is provided a bonus game controller for 30 use with a plurality of gaming machines in networked relationship with the bonus game controller, the bonus game controller comprising: a trigger determiner arranged to determine whether a bonus trigger signal has occurred at a first gaming 35 machine of the plurality of gaming machines, the bonus game controller being arranged to implement a first play 4990332_1 (GHMatters) P76390.AU.2 2 of a bonus game when the bonus trigger signal occurs at the first gaming machine; and a bonus prize allocator arranged to allocate a bonus prize to the first gaming machine, the bonus prize having 5 a total value that is based on: a) an outcome of the first play of the bonus game; and b) an outcome of at least one second play of the bonus game that occurs within a qualification period, wherein the at least one second play of the bonus game is initiated as a consequence of 10 determining that the bonus trigger signal has occurred at a second gaming machine of the plurality of gaming machines, the second gaming machine being different to the first gaming machine. 15 In one embodiment, the qualification period is a specific period of time from implementation of the first play of the bonus game. The time period may be fixed or may be pseudo randomly selected. 20 In an alternative embodiment, the qualification period is a specific number of second plays of the bonus game subsequent to implementation of the first play of the bonus game. The number of second plays of the bonus game may be fixed or may be pseudo randomly selected. 25 In an alternative embodiment, the game controller is arranged such that the qualification period commences when the bonus game trigger signal occurs at the first gaming machine and ends when an end trigger signal occurs at a 30 gaming machine. In one embodiment, the game controller is arranged such that for each gaming machine associated with a bonus trigger signal during the qualification period, a first 35 play of the bonus game is implemented and the gaming machine is allocated a bonus prize, the bonus prize having a total value that is based on: a) an outcome of the first 4990332_1 (GHMatters) P76390.AU.2 3 play of the bonus game; and b) an outcome of at least one second play of the bonus game that occurs after the first play of the bonus game up to expiration of the qualification period. 5 Each gaming machine may be arranged to generate a bonus trigger signal when a predefined game outcome occurs, for example, when a predefined game outcome occurs such as appearance of a special symbol, or appearance of a 10 predefined combination of symbols during implementation of a base game. The trigger signal could also be generated by another event apart from a predefined game outcome such as a 15 random trigger delivered by a controller such as described in Olive, US Patent 7,056,215 the disclosure of which is incorporated by reference, or randomly, or pseudo-randomly determined by a system controller. 20 In one embodiment, the game controller is arranged such that the qualification period commences when the bonus trigger signal first occurs at the first gaming machine (or other trigger) after expiration of a previous qualification period. 25 In one embodiment, the game controller is arranged such that each gaming machine associated with a bonus trigger signal has a respective associated qualification period. 30 In one embodiment, the bonus prize allocated to the first gaming machine associated with the trigger signal by the bonus game controller is the sum of the bonus prize, if any, obtained during implementation of the first play of the bonus game, and at least a proportion of one or more 35 other bonus prizes, if any, obtained during implementation of the at least one second play of the bonus game implemented within the qualification period. 4990332_1 (GHMatters) P76390.AU.2 4 In one embodiment, the bonus prize allocated to the first gaming machine by the bonus game controller is the sum of the bonus prize, if any, obtained during implementation of the first play of the bonus game and all bonus prizes 5 obtained during implementation of the at least one second play of the bonus game implemented within the qualification period. In one variation, the game controller may be arranged to 10 multiply an amount of the bonus prize received by the first gaming machine if the first gaming machine is associated with an additional bonus trigger signal during the qualification period. The first gaming machine may be arranged so that when the first gaming machine is 15 associated with the additional bonus trigger signal during the qualification period, the player has the option to multiply the amount of the bonus prize or to receive an additional bonus prize, if any, based on implementation of an additional first play of the bonus game and based on 20 the at least one second play of the bonus game implemented within the qualification period. According to a second aspect of the present invention there is provided a gaming system comprising: 25 a plurality of gaming machines, each gaming machine being arranged to implement a base game; and a bonus game controller according to the first aspect of the present invention. 30 In one embodiment, the gaming system comprises a display arranged to display bonus games implemented by the bonus game controller. The display may be configured so as to be viewable by all players of gaming machines associated with the gaming system. 35 The trigger determiner and the bonus prize allocator may be at least partly implemented using a processor. 4990332_1 (GHMatters) P76390.AU.2 5 In accordance with a third aspect of the present invention, there is provided a method of gaming, the method comprising: implementing a first play of a bonus game when a 5 bonus game trigger signal occurs at a first gaming machine of a plurality of gaming machines; defining a qualification period when the bonus game trigger signal occurs at the first gaming machine; and allocating a bonus prize to the first gaming machine, 10 the bonus prize having a total value that is based on: a) an outcome of the first play of the bonus game; and b) an outcome of at least one second play of the bonus game that occurs within the qualification period, wherein the at least one second play of the bonus game is 15 initiated as a consequence of determining that the bonus trigger signal has occurred at a second gaming machine of the plurality of gaming machines, the second gaming machine being different to the first gaming machine. In accordance with a fourth aspect of the present invention, 20 there is provided a computer program arranged when loaded into a computer to instruct the computer to operate in accordance with a bonus game controller, the bonus game controller comprising: a trigger determiner arranged to determine whether a 25 bonus trigger signal has occurred at a first gaming machine of the plurality of gaming machines, the bonus game controller being arranged to implement a first play of a bonus game when the bonus trigger signal occurs at the first gaming machine; and 30 a bonus prize allocator arranged to allocate a bonus prize to the first gaming machine, the bonus prize having a total value that is based on: a) an outcome of the first play of the bonus game; and b) an outcome of at least one second play of the bonus game that occurs within a 35 qualification period, wherein the at least one second play of the bonus game is initiated as a consequence of determining that the bonus trigger signal has occurred at 4990332_1 (GHMatters) P76390.AU.2 6 a second gaming machine of the plurality of gaming machines, the second gaming machine being different to the first gaming machine. 5 In accordance with a fifth aspect of the present invention, there is provided a computer readable medium having computer readable program code embodied therein, the computer readable program code being arranged when loaded into a computer to cause the computer to operate in 10 accordance with bonus game controller, the bonus game controller comprising: a trigger determiner arranged to determine whether a bonus trigger signal has occurred at a first gaming machine of the plurality of gaming machines, the bonus 15 game controller being arranged to implement a first play of a bonus game when the bonus trigger signal occurs at the first gaming machine; and a bonus prize allocator arranged to allocate a bonus prize to the first gaming machine, the bonus prize having 20 a total value that is based on: a) an outcome of the first play of the bonus game; and b) an outcome of at least one second play of the bonus game that occurs within a qualification period, wherein the at least one second play of the bonus game is initiated as a consequence of 25 determining that the bonus trigger signal has occurred at a second gaming machine of the plurality of gaming machines, the second gaming machine being different to the first gaming machine. 30 Brief Description of the Drawings The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: 35 Figure 1 is a schematic diagram of a gaming system in accordance with an embodiment of the present invention; 4990332_1 (GHMatters) P76390.AU.2 7 Figure 2 is a schematic block diagram illustrating operative components of a bonus game controller of the gaming system shown in Figure 1; Figure 3 is a diagrammatic representation of a gaming 5 device of the gaming system shown in Figure 1; Figure 4 is a schematic block diagram of operative components of the gaming device shown in Figure 3; Figure 5 is a schematic block diagram of components of a memory of the gaming device shown in Figure 3; and 10 Figure 6 is a flow diagram illustrating a method of gaming in accordance with an embodiment of the present invention. Description of an Embodiment of the Invention 15 Referring to Figure 1 of the drawings, there is shown a gaming system 10 including multiple player operable gaming devices 12, each of which in this example is a gaming machine arranged to implement a probabilistic wagering 20 base game of the type wherein a player wagers a bet amount, and a game outcome is determined in a probabilistic way. With some such probabilistic games, several symbols from a set of symbols are randomly displayed, and a game outcome is determined on the basis 25 of the displayed symbols. While the following description is directed to a probabilistic game it should be understood that the present invention could apply to pseudo-probabilistic 30 games such as Class II games as well, e.g. lottery or Bingo based games. The gaming devices 12 communicate with a bonus game controller 14 through a local network 16, the bonus game 35 controller 14 being arranged to implement a bonus game when a bonus trigger occurs at a gaming device 12. 4990332_1 (GHMatters) P76390.AU.2 8 The gaming system 10 also comprises a display controller 18 and a display 20, the display controller receiving data from the bonus game controller 14 indicative of a bonus game and controlling the display 20 so as to display a 5 representation of the bonus game on the display 20. In this example, the display 20 is relatively large and is displayed at a location such that players of the gaming devices are able to see the bonus game whilst playing a 10 base game on one of the gaming devices. Implementation of a bonus game by the bonus game controller 14 commences when a bonus trigger is determined by the bonus game controller 14 to have occurred at a 15 gaming device 12. In this example, a bonus trigger may be generated by a gaming device 12 when a predetermined game outcome occurs, on the basis of a game event occurring during a base game such as display of a particular symbol, a predetermined combination of symbols or in any other 20 suitable way. The present gaming system operates such that each of the gaming devices 10 implements a base game and during implementation of a base game is able to generate a bonus 25 trigger which causes the bonus game controller 16 to implement a first bonus game. The bonus game controller 14 allocates a prize to a player of a triggering gaming device 12 (the gaming device 12 where the trigger was displayed during the play of the base game) based on a 30 defined first prize, if any, obtained by the player during implementation of the first bonus game plus at least a portion of any prizes obtained by other players during implementation of at least some other bonus games subsequently triggered by other gaming devices 12 or re 35 triggered by the player obtaining the first trigger condition during a qualification period. 4990332_1 (GHMatters) P76390.AU.2 9 For example, a player of a first gaming device 12 which triggers a first bonus game may receive the sum (or a portion of the sum) of prizes obtained during the first bonus game and prizes obtained during any subsequent bonus 5 games triggered by other gaming devices 12 within a predefined time period after triggering the first bonus game, or may receive the sum of prizes obtained during the first bonus game and obtained during a predefined number of subsequent bonus games triggered by other gaming 10 devices. In this way, players of all gaming devices are able to be involved in the bonus game arrangement, and in particular have an incentive to achieve a bonus trigger early in the bonus cycle so as to increase the likelihood of obtaining a higher bonus prize. 15 In an alternative arrangement, the bonus game controller 14 implements sets of bonus games based on a predefined time period or based on a predefined number of bonus games. With this arrangement, each trigger causes a 20 sliding bonus game set to commence so that for each player of a triggering gaming device 12 the same number of contributing subsequent bonus games, or the same time period for contributing subsequent bonus games, is provided. 25 The gaming system 10 can take a number of different forms. In a first form, a gaming device in the form of a stand alone gaming machine is provided wherein all or most 30 components required for implementing the base game are present in a player operable gaming machine. In a second form, a distributed architecture is provided wherein some of the components required for implementing 35 the base game are present in a gaming device in the form of a player operable gaming terminal and some of the 4990332_1 (GHMatters) P76390.AU.2 10 components required for implementing the base game are located remotely relative to the gaming terminal. For example, a "thick client" arrangement may be used 5 wherein part of the base game is executed on a gaming terminal and part of the base game is executed by the gaming server, or a "thin client" arrangement may be used wherein most of the base game is executed remotely by the gaming server and a gaming terminal is used only to 10 display audible and/or visible gaming information to the player and receive gaming inputs from the player. However, it will be understood that other arrangements are envisaged. For example, an architecture may be provided 15 wherein the respective functions of the gaming device and the gaming server are selectively modifiable. For example, the gaming system may operate in stand alone gaming machine mode, "thick client" mode or "thin client" mode depending on the base game being played, operating 20 conditions, and so on. Other variations will be apparent to persons skilled in the art. Operative components of the bonus game controller 14 are shown in more detail in Figure 2. 25 The bonus game controller 14 includes a processor 21 arranged to process bonus game instructions and output bonus game outcomes to the display controller 18. Typically, the game instructions are stored as program 30 code in a memory that can also be hardwired. It will be understood that in this specification the term "processor" is used to refer generically to any device that can process game play instructions and may include a microprocessor, microcontroller, programmable logic device 35 or other computational device such as a personal computer or a server. 4990332_1 (GHMatters) P76390.AU.2 11 The processor 21 implements a bonus game and operates in association with a random number generator (RNG) 24 to produce probabilistic game outcomes. 5 It will be appreciated that the random number generator 24 may be of a type which is arranged to generate pseudo random numbers based on a seed number, and that in this specification the term "random" will be understood accordingly to mean truly random or pseudo random. 10 The processor 21 cooperates with a trigger detector 26 arranged to test for and determine occurrence of bonus triggers at the gaming devices 12 and to notice the bonus triggers to the processor 20. On occurrence of a bonus 15 trigger notification at a first gaming device 12, the processor 21 implements a first bonus game associated with the first gaming device 12 and allocates any resulting prize to the first gaming device 12. Occurrence of the bonus trigger also commences a qualification period during 20 which other gaming devices 12 are able to trigger a bonus game and at least a portion of the prizes awarded during the other bonus games are added to the prize awarded to the first gaming device. 25 In this example, the qualification period is a predefined period of time determined using a timer 28 which is activated by the processor 20 on receipt of a bonus trigger notification from the trigger detector 26. Alternatively, the qualification period is a predefined 30 number of bonus games which are triggered subsequent to receipt of a bonus trigger notification from the trigger detector 26. The predefined time period or number of bonus games may be fixed or may be variable, for example pseudo randomly selected using the random number generator 35 24 and the processor 21. As a further alternative, the qualification period may be determined based on occurrence of a commencement trigger signal at a gaming device 12 and 4990332_1 (GHMatters) P76390.AU.2 12 occurrence of an end trigger signal at the same or a different gaming device 12. The bonus game controller 14 also comprises an outcome 5 evaluator 30 which in accordance with the bonus game instructions 22 determines bonus game outcomes based the displayed bonus game results, and a prize allocator 32 arranged to calculate the appropriate prize, if any, to be awarded to a triggering gaming device 12 based on the 10 prize, if any, allocated to an initial triggering gaming device and based on any prizes awarded to other gaming devices 12 which trigger during the qualification period. It will be understood that the bonus game implemented by 15 the bonus game controller 14 may be of a type wherein a set of symbols are provided and a subset of the symbols are selected and displayed on the display 18, with game outcomes being determined on the basis of the symbols displayed and/or on the basis of the positions of the 20 displayed symbols on the display or the positions of the displayed symbols relative to other displayed symbols. A suitable bonus game is a spinning reel type game, a card type game, a Keno type game, and so on. The bonus game may also include an element of player interaction such as 25 choices of games, selection of elements of a bonus game from an offered set of selections or even a game which has an element of skill such as controlling a race car or horse, selection of pathways from a set of pathways play of a Blackjack or Poker hand and the like. 30 In the embodiments described below, the trigger detector 26, the timer 28, the outcome evaluator 30, and the prize allocator 32 are at least partly implemented using the processor 21 and associated software, although it will be 35 understood that other implementations are envisaged. A gaming device 40 of stand alone type, hereinafter 4990332_1 (GHMatters) P76390.AU.2 13 referred to as a gaming machine, is illustrated in more detail in Figure 3. The gaming machine 40 includes a console 42 having a display 44 on which is displayed representations of a base game 46 that can be played by a 5 player. A mid-trim 50 of the gaming machine 40 houses a bank of buttons 52 for enabling a player to interact with the gaming machine during game play, including enabling the player to select the bet amount. The mid-trim 50 also houses a credit input mechanism 54 which in this example 10 includes a coin input chute 54A and a bill collector 54B. A top box 56 may carry artwork 58, including for example pay tables and details of bonus awards and other information or images relating to the game. Further 15 artwork and/or information may be provided on a front panel 59 of the console 52. A coin tray 60 is mounted beneath the front panel 59 for dispensing cash payouts from the gaming machine 40. 20 The display 44 is in the form of a video display unit, particularly a cathode ray tube screen device. Alternatively, the display 44 may be a liquid crystal display, plasma screen, any other suitable video display unit. The top box 56 and/or the front panel 59 may also 25 include a display, for example a video display unit, which may be of the same type as the display 44, or of a different type. A player marketing module (PMM) 62 having a display 64 is 30 connected to the gaming machine 40. The main purpose of the PMM 62 is to allow the player to interact with a player loyalty system. The PMM has a magnetic card reader for the purpose of reading a player tracking device, for example as part of a loyalty program. However other 35 reading devices may be employed and the player tracking device may be in the form of a card, flash drive or any other portable storage medium capable of being read by the 4990332_1 (GHMatters) P76390.AU.2 14 reading device. In this example, the PMM 62 is a Sentinel III device produced by Aristocrat Technologies Pty Ltd. The top box 58, front panel 59 and/or the display 44 may 5 further display advertising material which in this example is displayed in response to advertising data downloaded from an advertising server. Figure 4 shows a block diagram of operative components 100 10 of a gaming device which may be a gaming machine of the type shown in Figure 3. The operative components 100 include a processor 102 and a memory 103. Instructions and data to control operation of 15 the processor 102 are stored in the memory 103. Typically, the gaming machine 100 will include both volatile and non-volatile memory and more than one of each type of memory, with such memories being collectively represented by the memory 103. 20 Figure 5 shows a block diagram of the main components of an exemplary memory 103. The memory 103 includes RAM 103A, EPROM 103B and a mass storage device 103C. The RAM 103A typically temporarily holds program files for 25 execution by the processor 102 and related data. The EPROM 103B may be a boot ROM device and/or may contain some system or game related code. The mass storage device 103C is typically used to store game programs, the integrity of which may be verified and/or authenticated by 30 the processor 102 using protected code from the EPROM 103B or elsewhere. The gaming machine 100 also includes meters 104 for purposes including ensuring regulatory compliance and 35 monitoring player credit, and an input/output (I/0) interface 105 for communicating with a player interface 120. 4990332_1 (GHMatters) P76390.AU.2 15 In the example shown in Figure 4, the player interface 120 includes at least one display 106, buttons 107 and the credit input mechanism 110, and also comprises a touch screen 107, a card and/or ticket reader 108 and a printer 5 109. Additional hardware may be included as part of the gaming machine 100, or hardware may be omitted as required for the specific implementation. In addition, the gaming machine 100 includes a 10 communications interface, for example a network card 112, which facilitates communications between the gaming machine 100 and the bonus game controller 14 through the network 16. 15 Operation of an exemplary gaming system 10 will now be described with reference to the flow diagram 140 shown in Figure 6. The flow diagram 120 illustrates steps 142 to 156 carried out in a method of gaming in accordance with an embodiment of the invention. 20 In the present example, three gaming devices 12 are shown associated with the local network 16, although it will be understood that in practice more than three gaming devices 12 would typically be present. 25 Each gaming device 12 implements 142 a probabilistic base game of the type wherein a player is able to place a bet and obtain a prize when the game results correspond to a winning outcome. In this example, the base game is a 30 spinning reel game of the type wherein several symbols from a set of symbols are randomly displayed, and a game outcome is determined on the basis of the displayed symbols. With such probabilistic games, the set of symbols may include standard symbols and function symbols, 35 and the game outcome is determined on the basis of the displayed standard symbols and the function associated with any displayed function symbol. For example, standard 4990332_1 (GHMatters) P76390.AU.2 16 symbols may resemble fruit such as apples, pears and bananas with a win outcome being determined when a predetermined number of the same fruit appear on a display in the same line, scattered, and so on. The function 5 associated with a function symbol may be for example a wild function wherein display of the function symbol is treated during consideration of the game outcome as any of the standard symbols. A function symbol may be represented as the word "WILD", a star, or by any other 10 suitable word or symbol. Other functions are also envisaged such as scatter functions, multiplier functions, repeat win functions, jackpot functions and feature commencement functions. 15 The base game could also be a Keno game, a video Poker game or other base games where the player makes a wager, and receives a displayed winning or losing outcome. The base game could be a Class II game such as a video lottery or Bingo game as well. 20 During implementation of a base game, if a trigger condition occurs 143, which may be display of a particular symbol or a particular combination of symbols in the base game, a trigger signal is sent from the gaming device 12 25 to the bonus game controller 14 through the network 16. On receipt of the trigger signal, the bonus game controller 14 starts 144 the timer 28 and implements 146 a bonus game, in this example a spinning reel type probabilistic game. The bonus game is shown on the 30 display 20 and is viewable by players of other gaming machines 12 associated with the gaming system 10. After completion of the bonus game, any prize obtained is allocated 150 to the player and stored as a cumulative 35 bonus prize amount. If the qualification period determined by the timer has not yet expired 152 and further bonus triggers have been received from the gaming 4990332_1 (GHMatters) P76390.AU.2 17 devices 12, the bonus game controller implements 146 one or more further bonus games associated with the other triggering gaming devices 12 in the order in which the bonus triggers are received after receipt of the initial 5 triggering signal. The bonus game controller then adds 150 any prize(s) obtained by the respective players associated with the further bonus games to the cumulative bonus prize amount. This procedure continues until the qualification period determined by the timer expires. 10 In one variation, the gaming system may be arranged to multiply the bonus amount received by a gaming device if the gaming device 12 generates an additional bonus trigger signal during the qualification period, e.g. "re 15 triggers". After expiration of the qualification period, the player of the initial triggering gaming device 12 (which also started the qualification period) is awarded a prize 20 amount equal to the stored cumulative prize amount. Players of other gaming devices 12 which have triggered after the initial trigger are awarded a bonus prize amount based on the respective bonus prize associated with the player, if any, plus bonus prize amounts associated with 25 subsequently triggering gaming devices 12 up to the end of the qualification period. As an alternative, instead of determining the qualification period in relation to a time period, the 30 qualification period may be determined in relation to a particular number of bonus games triggered after the initial triggering bonus game. As a further alternative, the qualification period may be 35 the same for each triggering gaming device 12 such that a sliding sequence of bonus games occurs after each trigger. With this arrangement, a cumulative prize amount may be 4990332_1 (GHMatters) P76390.AU.2 18 recorded for each triggering gaming device 12 and the gaming system 10 may be arranged such that each gaming device 12 receives a prize amount equal to the respective stored cumulative prize amount. 5 It should be understood that while the jackpot controller 14 could be associated with a bank of gaming devices 12 it could also be implemented through software operating at a remote location such as software incorporated into the 10 casino management system such as the OASIS system manufactured and sold by Aristocrat Technologies Inc. of Las Vegas, Nevada. While the above example is described in relation to a 15 gaming system having gaming devices which are disposed at the same location, it will be understood that other arrangements are possible. For example one or more of the gaming devices may be located remotely relative to the other gaming devices. 20 It will also be understood that instead of providing a display which is relatively large and disposed at a location such that players of gaming devices are able to see the bonus game whilst playing a game using a gaming 25 device, as an alternative, the gaming system may be arranged such that bonus games are in addition or alternatively displayed on the gaming devices. Modifications and variations as would be apparent to a 30 skilled addressee are deemed to be within the scope of the present invention. 4990332_1 (GHMatters) P76390.AU.2

Claims (40)

1. A bonus game controller for use with a plurality of gaming machines in networked relationship with the bonus 5 game controller, the bonus game controller comprising: a trigger determiner arranged to determine whether a bonus trigger signal has occurred at a first gaming machine of the plurality of gaming machines, the bonus game controller being arranged to implement a first play 10 of a bonus game when the bonus trigger signal occurs at the first gaming machine; and a bonus prize allocator arranged to allocate a bonus prize to the first gaming machine, the bonus prize having a total value that is based on: a) an outcome of the first 15 play of the bonus game; and b) an outcome of at least one second play of the bonus game that occurs within a qualification period, wherein the at least one second play of the bonus game is initiated as a consequence of determining that the bonus trigger signal has occurred at 20 a second gaming machine of the plurality of gaming machines, the second gaming machine being different to the first gaming machine.

2. A bonus game controller as claimed in claim 1, 25 wherein the qualification period is a specific period of time from implementation of the first play of the bonus game.

3. A bonus game controller as claimed in claim 2, 30 wherein the time period is fixed.

4. A bonus game controller as claimed in claim 2, wherein the time period is pseudo randomly selected. 35

5. A bonus game controller as claimed in claim 1, wherein the qualification period is a specific number of 4990332_1 (GHMatters) P76390.AU.2 20 second plays of the bonus game subsequent to implementation of the first play of the bonus game.

6. A bonus game controller as claimed in claim 5, 5 wherein the number of second plays of the bonus game is fixed.

7. A bonus game controller as claimed in claim 5, wherein the number of second plays of the bonus games is 10 pseudo randomly selected.

8. A bonus game controller as claimed in claim 1, wherein the bonus game controller is arranged such that the qualification period commences when a bonus game 15 trigger signal occurs at the first gaming machine and ends when an end trigger signal occurs at a gaming machine.

9. A bonus game controller as claimed in any one of the preceding claims, wherein the bonus game controller is 20 arranged such that for each gaming machine associated with a bonus trigger signal during the qualification period, a first play of the bonus game is implemented and the gaming machine is allocated a bonus prize, the bonus prize having a total value that is based on: a) an outcome of the first 25 play of the bonus game; and b) an outcome of at least one second play of the bonus game that occurs after the first play of the bonus game up to expiration of the qualification period. 30

10. A bonus game controller as claimed in any one of the preceding claims, wherein the bonus game controller is arranged such that the qualification period commences when the bonus trigger signal occurs at the first gaming machine after expiration of a previous qualification 35 period. 4990332_1 (GHMatters) P76390.AU.2 21

11. A bonus game controller as claimed in any one of the preceding claims, wherein the bonus game controller is arranged such that a respective qualification period is associated with each gaming machine which is associated 5 with a bonus trigger signal.

12. A bonus game controller as claimed in any one of the preceding claims, wherein the bonus prize allocated to the first gaming machine by the bonus game controller is the 10 sum of the bonus prize, if any, obtained during implementation of the first play of the bonus game and at least a proportion of one or more other bonus prizes, if any, obtained during implementation of the at least one second play of the bonus game implemented within the 15 qualification period.

13. A bonus game controller as claimed in claim 12, wherein the bonus prize allocated to the first gaming machine by the bonus game controller is the sum of the 20 bonus prize, if any, obtained during implementation of the first play of the bonus game and all bonus prizes obtained during implementation of the at least one second play of the bonus game implemented within the qualification period. 25

14. A bonus game controller as claimed in any one of claims 1 to 11, wherein the bonus game controller is arranged to multiply an amount of the bonus prize allocated to the first gaming machine if an additional bonus trigger 30 signal occurs at the first gaming machine during the qualification period.

15. A bonus game controller as claimed in claim 14, wherein the bonus game controller is arranged so that when 35 the additional bonus trigger signal occurs at the first gaming machine during the qualification period, the player has the option to multiply the amount of the bonus prize 4990332_1 (GHMatters) P76390.AU.2 22 or to receive an additional bonus prize, if any, based on implementation of an additional first play of the bonus game and based on the at least one second play of the bonus game implemented within the qualification period. 5

16. A gaming system comprising: a plurality of gaming machines, each gaming machine being arranged to implement a base game; and a bonus game controller as claimed in any one of the 10 preceding claims.

17. A gaming system as claimed in claim 16, wherein each gaming machine is arranged to generate a bonus trigger signal when a predefined game outcome occurs. 15

18. A gaming system as claimed in claim 17, wherein the predefined game outcome comprises appearance of a special symbol, or appearance of a predefined combination of symbols during implementation of a base game. 20

19. A gaming system as claimed in any one of the claims 16 to 18, wherein the gaming system comprises a display arranged to display plays of the bonus game implemented by the bonus game controller. 25

20. A gaming system as claimed in any one of claims 16 to 19, wherein the gaming system is arranged to display plays of the bonus game implemented by the bonus game controller on at least one gaming machine. 30

21. A gaming system as claimed in any one of claims 16 to 20, comprising at least one gaming terminal and a gaming server arranged to cooperate with the at least one gaming terminal so as to implement a game on each respective 35 gaming terminal. 4990332_1 (GHMatters) P76390.AU.2 23

22. A gaming system as claimed in any one of claims 16 to 21, wherein the trigger determiner and the bonus prize allocator are at least partly implemented using a processor. 5

23. A method of gaming, the method comprising: implementing a first play of a bonus game when a bonus game trigger signal occurs at a first gaming machine of a plurality of gaming machines; 10 defining a qualification period when the bonus game trigger signal occurs at the first gaming machine; and allocating a bonus prize to the first gaming machine, the bonus prize having a total value that is based on: a) an outcome of the first play of the bonus game; and b) an 15 outcome of at least one second play of the bonus game that occurs within the qualification period, wherein the at least one second play of the bonus game is initiated as a consequence of determining that the bonus trigger signal has occurred at a second gaming 20 machine of the plurality of gaming machines, the second gaming machine being different to the first gaming machine.

24. A method as claimed in claim 23, comprising defining 25 the qualification period as a specific period of time from implementation of the first play of the bonus game.

25. A method as claimed in claim 24, wherein the time period is fixed. 30

26. A method as claimed in claim 24, wherein the time period is pseudo randomly selected.

27. A method as claimed in claim 23, comprising defining 35 the qualification period as a specific number of second plays of the bonus game subsequent to implementation of the first play of the bonus game. 4990332_1 (GHMatters) P76390.AU.2 24

28. A method as claimed in claim 27, wherein the number of second plays of the bonus game is fixed.

29. A method as claimed in claim 27, wherein the number 5 of second plays of the bonus game is pseudo randomly selected.

30. A method as claimed in claim 23, comprising commencing the qualification period when the bonus game 10 trigger signal occurs at the first gaming machine and ending the qualification period when an end trigger signal occurs at a gaming machine.

31. A method as claimed in any one of claims 23 to 30, 15 comprising, for each gaming machine which generates a bonus trigger signal during the qualification period: implementing a first play of the bonus game; and allocating a bonus prize, the bonus prize having a total value that is based on: a) an outcome of the first 20 play of the bonus game; and b) an outcome of at least one second play of the that occurs after the first play of the bonus game up to expiration of the qualification period. 25

32. A method as claimed in any one of claims 23 to 31, comprising commencing the qualification period when the bonus trigger signal first occurs at a gaming machine after expiration of a previous qualification period. 30

33. A method as claimed in any one of claims 23 to 32, comprising associating a respective qualification period with each gaming machine associated with a bonus trigger signal. 35

34. A method as claimed in any one of claims 23 to 33, wherein the bonus prize allocated to the first gaming machine is the sum of the bonus prize, if any, obtained 4990332_1 (GHMatters) P76390.AU.2 25 during implementation of the first play of the bonus game and at least a proportion of one or more other bonus prizes, if any, obtained during implementation of the at least one second play of the bonus game that occurs within 5 the qualification period.

35. A method as claimed in claim 34, wherein the bonus prize allocated to the first gaming machine is the sum of the bonus prize, if any, obtained during implementation of 10 the first play of the bonus game and all bonus prizes obtained during implementation of the at least one second play of the bonus game that occurs within the qualification period. 15

36. A method as claimed in any one of claims 23 to 35, comprising multiplying the an amount of the bonus prize allocated to the first gaming machine if an additional bonus trigger signal occurs at the first gaming machine during the qualification period. 20

37. A method as claimed in claim 36, comprising providing a player with an option to multiply the allocated amount of the bonus prize or to receive an additional bonus prize, if any, based on implementation of an additional 25 first play of the bonus game and based on the at least one second play of the bonus game implemented within the qualification period when an additional bonus trigger signal occurs at the first gaming machine during the qualification period. 30

38. A computer program arranged when loaded into a computer to instruct the computer to operate in accordance with a bonus game controller as claimed in any one of claims 1 to 15. 35

39. A computer readable medium having computer readable program code embodied therein, the computer readable 4990332_1 (GHMatters) P76390.AU.2 26 program code being arranged when loaded into a computer to cause the computer to operate in accordance with a bonus game controller as claimed in any one of claims 1 to 15. 5

40. A bonus game controller, or a gaming system, or a method of gaming substantially as hereinbefore described with reference to, and as shown in, one or more of the accompanying drawings. 4990332_1 (GHMatters) P76390.AU.2