Meffert's Ghost Cube
Designed by puzzle innovator Adam G. Cowan, the Ghost Cube has a simple goal that is anything but easy to complete. Just form the 3D rotational puzzle into a 3" x 3" x 3" cube, but misaligned layers, odd shaped pieces, and only one color make it deceivingly difficult to solve. Weighs 8 ounces. Plastic.
The goal of this puzzle is easy to understand - form into the shape of a cube - but the uniform color of the panels make it deceivingly difficult to solve. The seemingly arbitrary directions in which the puzzle turns makes this a challenge even for expert twisty puzzle enthusiasts.