Voltorb Flip was better, because you had to rely SO much more on luck with the slots, and in Voltorb Flip it was a lot easier to get coins.
Never really got into the slots, they were too luck based for me to be interested in. Voltorb Flip though? Very fun game, it's much more fair and logic based, and it's relatively easy to win coins there if you know what you're doing.
I'm not really a fan of either (the entire concept of playing a mini game for hours to unlock rare items/Pokemon relatively early in the game turns me off), but I prefer Voltorb Flip, as it actually requires strategy and not straight reliance on luck.
On a slight tangent but still related, is it possible part of Grimsley's inspiration was a joke about how the slot machines were banned? Like, "If we can't have slot machines because they 'promote gambling', we'll put in a gambler!"
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