Getting an average of 50x for every bonus round is in fact not bad, I already reached too many bonus rounds on other slots where I only received 5 -10x.
The slot you were playing probably was a medium / low volatility slots that gives a decent amount of bonus rounds but it doesnt really pay off that much. Low / medium volatility slots are good if you are playing with high stake per spin but if you are only playing for less than $5 then. Alot of streamers usually spin $50 - 100 per spin on these kind of slots.
I'd say high / extreme volatility slots might pay off better ( if you are lucky
)I had this also a couple of times on high volatile slots such as Rise of Merlin. These days I play a lot "Miles Bellhous and the gears of time" and I reach quite often the bonus round and get most of the time a multiplier of 30x and sometimes 50x or even 100x.
I know high volatile slots will pay better and that you can get x5000 multipliers if you get lucky, but for the moment I don't have that luck
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