I like Mario game. I don’t remember now that I spend how much hour by hitting this cubes and trying to find some mushrooms or a few coin. I think this cube is a good theme for a take out the coin puzzle.
My firs design “Lost coin” isn’t a real cube. It’s a rectangular box and the slit for taking out is on a side face. I made this one in a perfect cube shape and the slit is at the top of the box. This shape is more confusing for occasional puzzle solvers. My friends try take out the coin by shaking the box in upside down position.
The internal mechanism of this puzzle is same with lost coin puzzle. I made this puzzle from plywood. Some puzzle enthusiasts can hate but plywood is a good material for box making.