While M.C. Escher's mind-bending staircases are taught in most elementary school classrooms, István Orosz's hand-drawn mysteries are less of a household name, although they're just as bizarre. Perhaps it is because of the unsettling skulls lurking behind the Durer-styled medieval scenes, which we first saw on Oddity Central.

Orosz, a Hungarian painter, is especially interested in optical illusions and visual tricks. We particularly love this quote of his from "The Physics of Invisibility": "There are things I can imagine and I can draw. There are things I can imagine but I cannot draw. But, could I draw something that I cannot imagine? That interests me greatly." Orosz's work toys with the relationship of truth and lies as his meticulously detailed scenes accurately depict a physical impossibility.

Scan through the slideshow below and see how many skulls you can decipher from Orosz's tricky penmanship. While some are easy to spot, others take a second to register. (If you visit Orosz's website you can see the skulls clearly in their thumbnail form.)

See a slideshow below, and let us know if you've been able to spot them all in the comments section.

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  • Can You Spot the Skull?

    "Ship of Fools" pieces by Istvan Orosz. See more <a href="http://www.gallerydiabolus.com/gallery/artist.php?id=utisz&page=135">here</a>

  • Can You Spot the Skull?

    "Ship of Fools" pieces by Istvan Orosz. See more <a href="http://www.gallerydiabolus.com/gallery/artist.php?id=utisz&page=135">here</a>

  • Can You Spot the Skull?

    "Ship of Fools" pieces by Istvan Orosz. See more <a href="http://www.gallerydiabolus.com/gallery/artist.php?id=utisz&page=135">here</a>

  • Can You Spot the Skull?

    "Ship of Fools" pieces by Istvan Orosz. See more <a href="http://www.gallerydiabolus.com/gallery/artist.php?id=utisz&page=135">here</a>

  • Can You Spot the Skull?

    "Ship of Fools" pieces by Istvan Orosz. See more <a href="http://www.gallerydiabolus.com/gallery/artist.php?id=utisz&page=135">here</a>

  • Can You Spot the Skull?

    "Ship of Fools" pieces by Istvan Orosz. See more <a href="http://www.gallerydiabolus.com/gallery/artist.php?id=utisz&page=135">here</a>

  • Can You Spot the Skull?

    "Ship of Fools" pieces by Istvan Orosz. See more <a href="http://www.gallerydiabolus.com/gallery/artist.php?id=utisz&page=135">here</a>

  • Can You Spot the Skull?

    "Ship of Fools" pieces by Istvan Orosz. See more <a href="http://www.gallerydiabolus.com/gallery/artist.php?id=utisz&page=135">here</a>

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