Gaming machine with random symbol selection

Abstract

A gaming machine includes a display and a game controller that provides a wagering game in which a plurality of symbol display positions are provided on the display. When a player stakes a wager on the outcome of the wagering game the game controller selects symbols for display sequentially. The set of symbols is dynamic, wherein at least two symbols from the symbol set are changed between at least certain symbol selections depending on a characteristic of a symbol selected in a previous selection. The display positions may be arranged in rows and columns.

1 . A gaming machine comprising a display and a game controller that provides a wagering game in which: 
 a plurality of symbol display positions arranged in a plurality of columns are provided on the display; and    when a player stakes a wager on an outcome of the wagering the game controller selects symbols from a set of symbols comprising a plurality of symbols according to a random selection process and the selected symbols are displayed in the display positions; and    if a winning combination of symbols is displayed the gaming machine awards a prize;    wherein at least one column comprises at least two display positions and for each column having two or more display positions:    the game controller selects from an original set of symbols allocated to that column the symbols for display in a first display position and sequentially selects symbols for the other display positions in the column; and    for each symbol selected after the selection for the first display position, the selection is made from a different set of symbols that is a modification of the original set of symbols, wherein the modification depends on a characteristic of the symbol selected in one or more previous selections;    and wherein at least one said winning combination of symbols comprises the display of particular symbols across the plurality of columns.    
   
   
       2 . The gaming machine of  claim 1 , wherein the at least one said winning combination of symbols comprises the display of a particular combination of symbols formed by taking the symbol selected for any one and only one display position in each column.  
   
   
       3 . The gaming machine of  claim 1 , wherein at least two of the columns comprise a different number of display positions.  
   
   
       4 . The gaming machine of  claim 1 , wherein the number of display positions in a column that are active for defining a winning combination is variable depending on the particular wager staked by the player.  
   
   
       5 . The gaming machine of  claim 1 , wherein the original set of symbols comprises a plurality of subsets of symbols, each said subset consisting of symbols that if displayed together across the plurality of columns would define a said winning combination, and wherein the modification of the original set of symbols comprises either removing or changing all symbols in the same subset as the symbol selected in the one or more previous selections.  
   
   
       6 . The gaming machine of  claim 5 , wherein at least one column comprises at least three display positions and wherein the modification to the set of symbols is cumulative so that no two symbols from the same subset can appear in the same column.  
   
   
       7 . The gaming machine of  claim 1 , wherein at least one column comprises at least three display positions and wherein the modification of the original set of symbols for the selection of a symbol for the third and any subsequent symbols positions is cumulative of the modifications made for the preceding display positions.  
   
   
       8 . A gaming machine comprising a display and a game controller that provides a wagering game in which a plurality of symbol display positions are provided on the display, and when a player stakes a wager on the outcome of the wagering game the game controller selects symbols from a set of symbols comprising a plurality of symbols according to a random selection process and the selected symbols are displayed in the display positions, and when a winning combination of symbols is displayed the gaming machine awards a prize to the player, the gaming machine being characterised in that the game controller selects at least two of the symbols sequentially and the set of symbols is dynamic, wherein at least two symbols from the symbol set are changed or removed between at least two successive symbol selections depending on a characteristic of a single symbol selected before the second of the two successive symbol selections.  
   
   
       9 . The gaming machine of  claim 8 , wherein the set of symbols comprises a subset of symbols consisting of symbols that would define a said winning combination if displayed together in a predetermined arrangement of display positions, and wherein when said single symbol is a symbol from the subset of symbols, the symbols that are changed or removed comprise the symbols in the same subset.  
   
   
       10 . The gaming machine of  claim 9 , wherein the set of symbols comprises a plurality of said subsets of symbols and wherein when said single symbol is a symbol from one of the plurality subsets of symbols, the symbols that are changed comprise the symbols in the same subset.  
   
   
       11 . The gaming machine of  claim 9 , wherein the symbols that are changed consist of the symbols in the same subset and no other symbols in the set of symbols are changed between the sequential selection of symbols.  
   
   
       12 . The gaming machine of  claim 8 , wherein the dynamic change comprises the addition of symbols to the set of symbols between the sequential selections.  
   
   
       13 . The gaming machine of  claim 8 , wherein the dynamic change comprises the altering of characteristics of symbols in the set between selections.  
   
   
       14 . The gaming machine of  claim 8 , wherein the characteristic of said single symbol is its identity, and the set of symbols is changed by removing all symbols of that identity from the set of symbols prior to the next symbol selection.  
   
   
       15 . A gaming machine comprising a display and a game controller for providing a wagering game in which a plurality of symbol display positions are provided on the display arranged in a matrix of m columns by n rows, and when a player stakes a wager on the outcome of a wagering game played on the system the game controller is arranged to play the wagering game in which symbols are randomly selected from a set of symbols and the selected symbols are displayed in the display positions, and if a winning combination of symbols is displayed a prize is awarded to the player, the gaming system being characterised in that the selection of each symbol in a column is independent of any other symbol selected in that column, and the set of symbols from which the symbols are selected changes as a consequence of each symbol selection made in a column.  
   
   
       16 . The gaming machine of  claim 15 , wherein the set of symbols from which the symbols are selected is changed so that it is not possible for a combination of symbols that represents a winning combination to be displayed in the display positions forming any one of the columns.  
   
   
       17 . A gaming machine comprising a display and a game controller for providing a wagering game in which a plurality of symbol display positions are provided on the display, and when a player stakes a wager on the outcome of a wagering game played on the system the game controller is arranged to randomly select symbols from a set of symbols and display the selected symbols in the display positions, and if a winning combination of symbols is displayed the player is awarded a prize, the gaming machine being characterised in that: 
 at least some of the symbols in the set comprise members of a family of symbols;    the symbols are selected sequentially from a first symbol display position to a subsequent symbol display position; and    the set of symbols from which each symbol is selected is altered for each selection after the first selection until said subsequent display position by removing from the set all those symbols belonging to a particular family if a symbol from that family was selected in a previous selection.    
   
   
       18 . The gaming machine of  claim 17 , wherein the symbol display positions are aligned in either a column or a row, and the first symbol display position is the first position in the column or row, and the subsequent symbol display position is the last symbol display position in the column or row.  
   
   
       19 . The gaming machine of  claim 17 , wherein the symbol display positions are arranged in an array of m columns by n rows, and the symbols are selected sequentially for the display positions in each column, the set of symbols for each column being at least substantially the same, winning outcomes comprising the selection of the same symbol in adjacent columns.  
   
   
       20 . The gaming machine of  claim 17 , wherein the number of symbol display positions in each column and/or each row depend on a characteristic of the wager which a player stakes on a game.  
   
   
       21 . A gaming machine comprising a display and a game controller for providing a wagering game in which a plurality of symbol display positions are provided on the display, and when a player stakes a wager on the outcome of a wagering game played on the system the game controller is arranged to randomly select symbols and display the selected symbols in the display positions, and if a winning combination of symbols is displayed the player is awarded a prize, the gaming machine being characterised in that: 
 the display positions are arranged in an array of m columns by n rows wherein m and n are greater than 1;    the symbol selected for display in each display position is individually selected from a set of symbols; and    the set of symbols from which a symbol is selected for at least one of the display positions differs from the set of symbols from which a symbol is selected for another display position so that despite the individual selection of the symbol for each display position, it is either: 
 not possible to display a winning combination of symbols along any one of the columns and is possible to display a winning combination of symbols along any one of the rows; or  
 not possible to display a winning combination of symbols along any one of the rows and is possible to display a winning combination of symbols along any one of the columns.  
   
   
   
       22 . A method of providing a game in which a player stakes a wager on one or more of the outcomes and if a winning combination results in an outcome on which the player has staked a wager an award is awarded, the method comprising representing a plurality of the outcomes on an electronic display as symbols in a plurality of adjacent display positions comprising a first display position to an nth display position, using an electronic controller to sequentially select the symbols for display in each of the first display positions from a set of symbols that is modified during the selection process so that a winning combination defined by a plurality of adjacent symbols can not be defined across the first display positions, and repeating the sequential selection process for each of the 2nd to the nth display positions.  
   
   
       23 . The method of  claim 22 , wherein a further plurality of outcomes on which a player may stake a wager are defined by combinations of symbols from the 1st to nth display positions of the outcomes defined by a plurality of adjacent display positions, one and only one symbol used in each of the display positions.  
   
   
       24 . The method of  claim 22 , wherein the plurality of adjacent display positions comprising a first display position to an nth display position are displayed in columns with the display positions aligned so as to form a matrix of display positions having n rows and m columns and wherein the set of symbols is modified by removing from eligibility for selection any symbol that if selected for the current display position, would represent part or all of a winning combination of symbols together with a previously selected symbol for an adjacent display position in the same column.  
   
   
       25 . The method of  claim 22 , wherein the plurality of adjacent display positions comprising a first display position to an nth display position are displayed in rows with the display positions aligned so as to form a matrix of display positions having m rows and n columns and wherein the set of symbols is modified by removing from eligibility for selection any symbol that if selected for the current display position, would represent part or all of a winning combination of symbols together with a previously selected symbol for an adjacent display position in the same row.