Gaming method and machine with bonus game

A method of conducting a wagering game, comprising:

• conducting a basic wagering game;
• and
• conducting a bonus game within the basic wagering game when a start-bonus outcome is detected in the basic game, the bonus game further comprising,
• determining a spin result, the spin result including a set of symbols positioned in a plurality of rows of symbol positions,
• displaying the spin result on a viewable display area,
• awarding a prize associated with the spin result,
• when a first trigger condition is met,
• adding a row to produce a second larger plurality of rows of symbol positions,
• determining a second spin result, the second spin result including a second set of symbols positioned in the second larger plurality of rows of symbol positions, and
• displaying the second spin result on the viewable display area,
• when a second trigger condition is met,
• removing a row of symbol positions, and
• when an end condition is met, ending the bonus game.

A method for conducting a wagering game, comprising:

• determining a spin result, the spin result including positions of symbols in a number of symbol positions;
• displaying the spin result on a viewable display area;
• awarding a prize associated with the spin result;
• increasing the number of symbol positions if a first trigger condition is met;
• decreasing the number of symbol positions if a second trigger condition is met;
• and
• ending the wagering game if an end condition is met.

A system for conducting a wagering game, comprising:

• a viewable display area, the viewable display area configured to display a variable number of symbol positions;
• a first trigger condition to increase the number of symbol positions;
• a second trigger condition to decrease the number of symbol positions;
• and
• a processor, the processor in communication with the viewable display area and configured to,
• determine a spin result, the spin result including positions of symbols in the rows of symbol positions,
• award a prize associated with the spin result,
• responsively increase the number of symbol positions on occurrence of the first trigger condition,
• responsively decrease the number of symbol positions on occurrence of the second trigger condition, and
• end the wager game on occurrence of a end condition.

A computer-readable medium storing instructions adapted to be executed by a processor, the instructions, when executed, defining a method for conducting a wagering game, the method comprising:

• determining a spin result, the spin result including a set of symbols positioned in a plurality of rows of symbol positions;
• displaying the spin result on a viewable display area;
• awarding a prize associated with the spin result;
• when a first trigger condition is met,
• adding a row to produce a second larger plurality of rows of symbol positions,
• determining a second spin result, the second spin result including a second set of symbols positioned in the second larger plurality of rows of symbol positions, and
• displaying the second spin result on the viewable display area,
• when a second trigger condition is met,
• removing a row of symbol positions;
• and
• when an end condition is met, ending the wagering game.