Cash Pump is a 12-reel video slot machine. You play on all 4 play areas: top-left, bottom-left, top-right and bottom-right. Each play area has 5 fixed paylines, for a total of 20 fixed paylines.
WILD symbols only appear on the center reel of each play area, substituting all symbols except SCATTER.
The STACKED WILDS feature is triggered when any center reel is fully occupied by WILD symbols. All WILD symbols are then duplicated in the corresponding positions on all other play areas, multiplying any win by either x1, x2, x3 or x4.
SCATTER symbols only appear on the center reel of each play area. 1 SCATTER symbol appearing on every play area (4 in total) will trigger 7 FREE SPINS.
During FREE SPINS, any SCATTER symbol appearing on any play area is collected. Each time 4 SCATTER symbols have been collected, an additional 5 FREE SPINS are awarded and the available multipliers for STACKED WILDS are increased. The first multiplier always increases by 1 (from x1 to x2, etc.); the second multiplier always increases by 2 (from x2 to x4, etc.); the third multiplier always increases by 3 (from x3 to x6, etc.); and the fourth multiplier always increases by 4 (from x4 to x8, etc.). The multipliers are unlimited, up to the point where the feature ends.