While looking for relaxing activities to do at home during quarantine, many people have broken out their jigsaw puzzles. But if you prefer your puzzles to be more challenging than relaxing, check out this one from ExpressItBest, which is available on Amazon for $22. The puzzle for adults consists of 150 clear pieces, and it takes a lot of brain power to put it together.

Every .75-inch piece in this set is perfectly transparent, which means the only clues you have as to what goes where are the outlines. The makers call the "practically impossible" brainteaser "our hardest puzzle for the most hardcore dissectologist." It's so difficult that ExpressItBest gives away one free custom puzzle a week to someone who posts a picture of the completed puzzle with the hashtag #Puzzibility on social media.

ExpressItBest/Amazon

If you succeed in solving it, you won't get a full-color photograph or a soothing landscape to display on your coffee table. Instead, you'll have a 10-by-12-inch clear rectangle and the satisfaction of conquering the near-impossible.

If this one still looks too easy for you, the wooden fractal puzzle, the infinite galaxy puzzle, and the 1000 color puzzle on this list may pose more of a challenge.

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