Gaming machine with substitute symbols

A gaming machine includes a display on which a plurality of display of display positions are displayed. A game controller is arranged to control images displayed on the display. The controller also controls playing of a game on the machine wherein a plurality of symbols are randomly selected and displayed on the display such that if a winning combination results, the machine pays a prize. The controller is operable, upon the occurrence of a predetermined triggering event, to generate a bonus symbol which is displayed in a first display position and, thereafter in at least one other display position. In predetermined circumstances, when the bonus symbol moves from a preceding display position, a residual symbol remains at the preceding display position and, when the bonus symbol appears at a subsequent display position, both the original bonus symbol and the residual bonus symbol operates as substitute symbols in their display positions.

RELATED APPLICATIONS

This application claims the benefit of the Australian application PQ 3520 filed Oct. 18, 1999 and the international application PCT/AU00/01233 filed Oct. 11, 2000.

FIELD OF THE INVENTION

The present invention relates to a gaming machine. More particularly, the invention relates to a gaming machine of the type commonly known as a slot machine, a fruit machine or a poker machine.

BACKGROUND TO THE INVENTION

Players who regularly play gaming machines of the type in question quickly tire of particular games. It is therefore necessary for manufacturers of these machines to introduce innovative game features that add interest to the games provided on such machines in order to keep the players amused and interested and therefore willing to continue playing the games.

These machines have become well known locally and abroad over a number of years. More particularly, the machines have recently gained considerable popularity throughout Australia with substantial amounts of money being wagered on these machines. There is a growing tendency for state governments to legalise the use of gaming machines by licensing operators, with resulting revenue gains through licence fees and taxation of moneys invested. The licensed operation of gaming machines is the subject of state legislation and regulation. For example, a minimum of 85% of monies invested must be returned as winnings. Manufacturers of gaming machines therefore must design their machines around these regulatory controls.

With the growth that has occurred in the gaming machine market, there is intense competition between manufacturers to supply various existing and new venues. When selecting a supplier of gaming machines the operator of a venue will often pay close attention to the popularity of various games with their patrons. Therefore, gaming machine manufacturers are keen to devise games which are popular with players as a mechanism for improving sales.

Various strategies have been tried in the past to make games more enticing to players such as, for example, the commonly known double-up feature whereby, if a player wins a particular game, that player can then risk the winnings of the game in a double-or-nothing mode in which they gamble on a subsequent, and often different, game such as whether a red or black card will be the next card drawn.

Other techniques adopted in the past have been to provide complexity in the numbering and combinations of indicia which would result in a win, thereby hoping to convince the player that there is a greater chance of winning and to keep their interest in a particular game.

The present invention provides a game feature in which, in response to a trigger condition, a substitute or substitute symbol is introduced, the substitute symbol having additional features.

SUMMARY OF THE INVENTION

According to the invention, there is provided a gaming machine which includes:a display means on which a plurality of display positions are displayed; anda game control means arranged to control images displayed on the display means, the control means also controlling playing of a game on the machine wherein a plurality of symbols are randomly selected and displayed on the display means such that, if a winning combination results, the machine pays a prize, the control means being operable, upon the occurrence of a predetermined triggering event, to generate a bonus symbol which is displayed in a first display position and, thereafter, in at least one other display position and, in predetermined circumstances, when the bonus symbol appears at one display position, a residual symbol remains and, when the bonus symbol appears at a subsequent display position, both the original bonus symbol and the residual symbol are taken into consideration in determining an award.

The present invention is applicable to video gaming machines of the traditional style in which the display means comprises a video simulation of a set of rotatable reels, each carrying a plurality of symbols. However, the invention is equally applicable to video draw poker machines in which a poker hand is displayed on the screen, the cards of the hand being selected from a standard 52 or 53 card deck, and other games such as keno, bingo, etc.

The bonus symbol may be any suitable bonus symbol such as a substitute/substitute symbol, a scatter symbol, a progressive symbol, second screen feature symbol, or the like. For ease of explanation, the invention will be described with reference to the special symbol being a substitute symbol. The substitute symbol may be triggered when a predetermined combination of symbols is “spun-up”. Instead, the substitute symbol may be triggered when a special symbol is displayed in a particular position on the display means, either alone or in conjunction with one or more other, special symbols also at particular display positions. For example, the feature may be triggered by a predetermined first symbol appearing in the first (or left hand) column of the display and a second, different symbol appearing in the last (or right hand) column of the display. The predetermined first symbol and second symbol may each be a background symbol arranged behind another symbol.

The substitute symbol may be any suitable symbol.

For example, the substitute symbol may be an arrow which is “shot” at the display and, when it hits one of the symbols, it substitutes as a substitute in that position. If the original symbol then “ignites”, the “flames” serve as the residual symbol. Instead, the arrow may be a “flaring arrow” which strikes one of the symbols. Animated flames may be displayed on the symbol where the arrow has pierced that symbol. The flames may substitute for all symbols except the scatter and any prizes in which the flames substitute will be paid. The flames may either continue to burn on that symbol for the duration of the feature or it may die out before the following arrow is fired. If the flames continue to burn, it continues to act as a substitute symbol throughout the feature whereas, if the flames die out before the next arrow is fired, it no longer acts as a substitute symbol.

In another embodiment, the substitute symbol may be in the form of a bird which migrates across the display to substitute for the conventional symbols of the reels. Where the bird lays an egg, the egg is the residual symbol.

In yet a further embodiment, the substitute symbol may be in the form of a penguin which migrates sequentially through each position on the display. In predetermined positions, a form of the penguin may be left behind which serves as the residual symbol.

DETAILED DESCRIPTION OF THE DRAWINGS

InFIG. 1, reference numeral10generally designates a gaming machine including a game, in accordance with the invention. The machine10includes a console12having a video display unit14. The video display unit14includes a screen16. Reels or reel strips18are simulated on the screen16. A keypad20is provided on the console12. The keypad20is operable to actuate “spinning” of the reel strips18.

A top box22is mounted above the screen16. The top box22displays one or more paytables24.

A coin tray26is mounted beneath the console12for cash payouts from the machine10.

As shown inFIG. 2of the drawings, a control system30is illustrated. A program which implements the game and user interface is run on a processor32of the control system30. The processor32forms part of a controller34which drives the screen16of the video display unit14and which receives input signals from sensors36. The sensors36include sensors associated with the keypad20. Instead, or in addition, the sensors36could include touch sensors mounted in the screen16.

The controller34also receives input pulses from a mechanism38indicating that a player has provided sufficient credit to begin playing. The mechanism38may be a coin input chute, a bill collector, a credit card reader, or any other type of validation device. Finally, the controller34drives a payout mechanism40which, for example, may be a coin hopper for feeding coins to the coin tray26to pay a prize once a predetermined combination of symbols carried on the reels18appears on the screen16.

Referring now toFIGS. 3 to 7of the drawings, various screen displays of the screen16of a feature, are illustrated. In this description, it is assumed that any winning combination on a payline pays a prize as opposed to, for example, only a left-to-right combination. During the feature, the only prizes that are paid are for combinations in which the arrow and/or flames substitute. This applies also in respect of the embodiment described below with reference toFIGS. 8 to 12of the drawings.

Once the button20is actuated, the reels18are spun up to form a display such as shown inFIG. 3of the drawings. As illustrated, various paylines42are provided on which combinations of symbols pay a prize. Assuming that a predetermined trigger condition has been met, a substitute symbol is generated which, in the embodiment illustrated, is an arrow (not shown). Thus, as shown inFIG. 4, the arrow pierces the symbol “9” in reel18.3to leave a “hole” illustrated at44. Thus, in this embodiment, the arrow as represented by the hole44acts as a substitute symbol so that a prize is paid for five of a kind (Kings).

A second step of the feature is illustrated inFIG. 5of the drawings, where the arrow hits the King symbol in reel18.2. This symbol46ignites to leave a representation of flames48which represents a residual substitute symbol. Then, the arrow44is fired at the symbol “10” in reel18.3which, in turn, bursts into flames48. Once again, the flames48remain behind and the arrow44strikes the Jack symbol in reel18.1as illustrated inFIG. 7of the drawings which does not ignite.

As a result of the combination illustrated inFIG. 5of the drawings and before the second arrow strikes the symbol “10” in reel18.3, the flames act as a substitute symbol such that a payment is made for four Jacks on payline four and for four Kings on payline one. In addition, the flames act as a substitute symbol for a combination of three Queens on payline five.

When the arrow strikes the symbol10in reel18.3, various additional combinations are created. Thus, due to the residual flames48in reel18.2(as described above with reference toFIG. 5), and the new substitute symbol44, (as illustrated inFIG. 6of the drawings), various additional winning combinations are created, 4×King on payline one, 3×Queen and 3×Jack on payline two, 4×Jack on payline four and 4×Queen and 3×King on payline five.

Finally, when the arrow strikes the Jack symbol in reel18.1as shown inFIG. 7of the drawings, a prize is then paid for 4×Kings on payline one, 4×Queens on payline two, 3×Jacks on payline two, 4×Jacks and 3×Kings on payline four as well as 4×Queens and 3×Kings on payline5.

Referring now toFIGS. 8 to 12, another embodiment of the invention described above with reference toFIGS. 3 to 7, is illustrated. With reference toFIGS. 3 to 7, like reference numerals refer to like parts, unless otherwise specified. However, this embodiment pays for prizes appearing in left to right and/or right to left combinations on a payline only as opposed to the “any” combination of the previous embodiment.

In this embodiment of the invention, the trigger condition is the presence of a background “haystack” symbol50spun up on reels18.1and18.5at the same time. When this occurs, as illustrated inFIG. 8of the drawings, the feature is triggered.

In this embodiment, a message (not shown) is displayed on the screen16to indicate that the player should hit a “Fire” button20.1(FIG. 1) on the keypad20.

The hitting of the “Fire” button initiates the feature. An animated arrow, as illustrated at52inFIG. 9of the drawings, flies up from a bottom of the screen16over the currently displayed reels18and comes to rest in one of the symbols. In this case, the arrow52strikes the “Wagon” symbol on reel18.3.

Assuming nine lines are being played, when the arrow52strikes the “Wagon” symbol in reel18.3, the arrow52ignites and substitutes for the “Wagon” symbol. Accordingly, in this embodiment, a win is paid for 3×King and 3×9 on payline seven.

The feature comprises the firing of a number of arrows, for example, seven arrows. Accordingly, once the first arrow52has been fired, and prizes paid, as the case may be, a second arrow54(FIG. 10) is fired. In this case, the arrow52burns out and dies down. In other words, the arrow52remains in the “Wagon” symbol on reel18.3but no longer substitutes.

The arrow54strikes the “Queen” symbol on reel18.3and ignites. In this case, a win is paid for 3×King and 3×9 on the third payline.

When a following arrow56is “fired” it strikes the “9” symbol on reel18.4. The arrow54continues burning in the “Queen” symbol on the reel18.3and, accordingly, the flaming arrow54continues to substitute. Hence, in the embodiment shown inFIG. 11of the drawings, a win is paid for 4×King and 3×9 on the third payline.

Yet a further arrow58is fired at the reels18and strikes the “9” symbol on reel18.5where it substitutes. Due to the fact that both the preceding arrows54,56continue burning, they also constitute substitute symbols. Accordingly, in respect of the embodiment shown inFIG. 12of the drawings, a win is paid for 5×King on payline three, 3×Wagon on payline seven, and all three of a kind on payline three except Kings and Scatters, i.e. the three burning arrows54,56and58substitute for all symbols except scatters.

The feature is continued until all the flaming arrows have been fired. When this occurs the message “Feature Completed” is displayed. All wins from the feature are accumulated on the win meter of the gaming machine10.

Instead of the flaming arrows, a goose or duck could be made to “waddle” from one position to the other and to pay prizes in which it substitutes. The goose or duck may or may not lay an egg at its previous symbol position before moving to the next position. The egg then acts as an additional or residual substitute symbol to be paid in addition to wins with the bird substituting at its current position.

In yet another embodiment of the invention, relating to the applicant's “Penguin Pays” game certain triggering combinations commence a feature involving an animated skating penguin. The animations start with the penguins skating to the top left-hand symbol on the screen16and progressively skating to each of the fifteen symbol positions on the screen16. At each position, all wins on which the skating penguin substitutes are paid. The embodiment of the new invention extends this feature also to include other penguins being left behind at random positions that the skating penguin visits. Every time the skating penguin moves to a new position, all wins will be paid in which the left-behind penguins substitute in addition to those wins with the skating penguins substituting.

Prizes are only paid during each step of the feature for combinations in which the substitute symbol and/or residual substitute symbol substitutes.

Hence, it is an advantage of the invention that a game is provided which will provide more entertainment for players and will result in increased payouts to the players.