For advanced jigsaw puzzle players, the standard 1000-piece board is child's play. But imagine if none of those pieces had a cute cat or weeping willow on the front to guide you.

The “Black Hell” puzzle ($26)—or “White Hell” ($30), depending on your color preference—by Japanese manufacturer Beverly features a single solid color on its front. Adding an extra layer of frustration, the company claims its micro-sized puzzle pieces are the “world’s smallest,” suitable only for the nimblest of fingers.

One reviewer said it took him 17 months to complete half the puzzle. Another commented, “This puzzle is the devil reincarnated into an inanimate object!”

Although the front of the puzzle is blank, different patterns are imprinted on its back to help users connect the dots. This apparently disappointed one especially masochistic puzzle enthusiast, who wrote that it was “less impossible than I had hoped.”

The recommended age for this puzzle is 7 years and up, but it’s safe to say that this devilishly hard task is best left to professionals.

While the Black Hell is certainly in the running for the most challenging jigsaw puzzle, it doesn’t top the chart for ones with the most pieces. Amazon sells a 40,000-piece puzzle featuring Disney characters, and there's a massive one from Kodak at more than 51,000 pieces, but it's usually sold out. If you want to just start at 1000 pieces, you can see a larger collection here.

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