Three kinds of slots are called multiplier slot machines. I have no idea which of them is the "official" version:
- The amount of coins multiply winnings.
Slots with payouts that multiply based on the amount of coins you put in are called multiplier slots by some players. In these machines it doesn't matter how much you bet in the sense that payouts in relation to the bet will be the same. (By betting more, you stand to win or lose more though, of course.)
- The amount of scatter symbols multiply winnings.
The other kind of multiplier slot machines have scatter symbols which multiply your winnings during that particular spin. (If you have no winning lines, there's nothing to multiply.)
- Incentive for betting maximum coins.
Bonus multiplier slots are the ones that offer an incentive for betting maximum coins (the jackpot prize is usually bigger with max. bets compared to other bet sizes). In these slot machines, it only makes sense to bet the maximum amount of coins.
- Winnings from a free spins round multiply.
In multiplier bonus slots, you go to a bonus round (or "free spins" round) and all your winnings from that bonus round are multiplied X amount of times.
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