Method of gaming, a gaming system and a game controller

A method of gaming for use with a gaming machine having a display, and a controller, the method comprising:

• selecting via the controller in at least one game round a plurality of symbols for display to a player in a set of display positions on the display;
• modifying via the controller the displayed symbols by 1) splitting an original subset of the display positions to at least two clone subsets of display positions, and 2) copying each symbol in the original subset of the display positions to said at least two clone subsets of the display positions which are identical to or laterally displaced from the original subset, in response to determining that a subset of the symbols should be cloned;
• determining via the controller an outcome based on the modified symbols;
• retaining via the controller the cloned symbols during one or more following cloned symbol game rounds;
• restricting via the controller the symbol selection in the following cloned symbol game rounds so that the display positions for reels containing the clone subsets are fixed relative to each other;
• and
• wherein the original subset is all the visible positions of an original reel and the cloned subsets are all the visible positions of clone reels, and non-visible symbols on the original reel are also copied to corresponding non-visible positions on the clone reels, so that the original and clone reels show the same symbols in each visible reel position in the following cloned symbol game rounds.