These 15" square, 500 piece jigsaw puzzles each bear the same picture on both the front and the back.
However, one side has been turned sideways making it very challenging to figure out which side is up!
Diabolically, each piece has been identically cut from both directions as well. So even an expert puzzler won't be able to tell one side… or one piece…from the other.
if you're ready for an ultimate extreme challenge, these are the puzzles for you.