I’ve never been able to solve a Rubik’s Cube. Granted, it’s been a good number of years since I actually attempted. Even still, that puzzle seems like such a daunting challenge. So sometimes it blows my mind when I see that people have found ways to actually make the Rubik’s Cube even harder.

If you really love a challenge, you can go for the Sudoku Cube, which combines the challenges of both the Rubik’s Cube and Sudoku. It only costs about $6, and is sure to give you hours of frustration while turning whole columns of numbers. If you’re good at both of these games, then this should prove rather entertaining.