The 4th reel to the right of the main 3x3 grid is the Multiplier Reel. Only the middle position of this reel counts. On every spin it displays one of six possible values: x1, x2, x3, x5, x10, or x15. Whatever value lands in the centre multiplies your entire line win accordingly. So a 20x Ruby payout with a x15 multiplier becomes 300x your stake. That is the kind of moment that makes this gems slot memorable.
The Extra Bet feature is activated by pressing the "Ex" icon at the bottom-left of the interface. Enabling it increases your base bet by 50 % (for example, a €1.00 spin becomes €1.50). In return, the x1 multiplier is removed from the 4th reel entirely, guaranteeing a minimum x2 multiplier on every spin and significantly boosting the probability of landing x5, x10, or x15 values.
Players must approach Extra Bet cautiously, as the 50 % premium on every spin drains balances significantly faster than standard play. For context, the UK Gambling Commission banned traditional bonus-buy mechanics in 2021, recognizing their potential to stimulate excessive wagering. A standard bonus buy in other slots typically costs 50-100x the base bet.