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I'm ready to be addicted again with this game lol

I don't actually know the term of that button, but if you clicked it the ball will increase its speed to fall down to the prize below. The button will make the ball faster to fall to the prize, Sometimes it's quite boring while waiting for the ball to fall especially if the player is only playing on a single ball.

Playing on a multiple balls and waiting for the balls to fall down to the prize is quite enjoyable, especially the sounds that many ball falling makes, My ears really like it. The only thing I am quite bored with is the single ball and the sound it is making.

But overall, It is a quite nice experience though.