Can you get the four blocks out of the box - and then get them back in? An interlocking puzzle that you must essentially solve blind as the pieces move within the box! If you can solve this one without the instructions, you've accomplished something special. It's annoyingly hard without look obvious, so be careful, this Nightmare Box just might keep you up all night!

Dimensions: 3" x 3" x 2"
Difficulty level: 4 (out of 6)