Slot machine including a plurality of video reel strips

A gaming machine comprising

• a controller for sequentially rearranging, on a display, symbol columns whose number is N and for, when an outcome of rearranging the symbol columns satisfies a predetermined condition, shifting a game mode from a base game mode to a second game mode different from the base game mode, the controller executing
• (4-1) a process in which with reference to a drawing table for determining symbol positions on which symbol columns whose number is the N are rearranged, the symbols are rearranged on the display for each unit game, and
• (4-2) a process in which for each unit game, based on a symbol column drawing table different from the drawing table, it is determined whether or not to modify each one part of the symbols to a wild symbol each on other symbol columns whose number is a predetermined number and less than a total number of symbol columns other than and except a symbol column which initially stops among the symbol columns whose number is the N, wherein in the symbol column drawing table,
• (a) there is a case where a predetermined number of symbol columns randomly selected from a group of the other symbol columns whose number is N−1 are selected from symbol columns which start from a symbol column stopping for the second time and are consecutively arranged, and
• (b) there is a case where the predetermined number of symbol columns randomly selected from the group of the other symbol columns whose number is the N−1 are inconsecutively selected, or the symbol column stopping for the second time is not selected and a predetermined number of symbol columns including a symbol column stopping for the third time and symbol columns stopping later than the third time are selected, and
• a probability with which the (a) is selected is set to be lower than a probability with which the (b) is selected.