An electronic gaming machine includes a game controller configured to (a) determine, during a base game, that a feature game trigger condition is satisfied; (b) activate a feature game within the base game; (c) display, a feature game play area associated with the feature game, the feature game play area including a plurality of zone patterns overlaid on the symbol display positions; (d) convert the symbol display positions into independent feature game reels; (e) generate a first game outcome by (i) holding a first set of feature game reels displaying the prize symbols while (ii) selecting and displaying a symbol for a second set of feature game reels; (f) determine that at least one zone pattern is complete with prize symbols; (g) apply a zone multiplier associated with the zone pattern to credit values within the zone pattern; and (h) award the incremented credit values to the player.