Wait, the Sonic X logo contains an optical illusion?

Sonic X, the anime series based on the Sonic the Hedgehog video game, was an integral part of many people's childhood. With 78 episodes in total, it saw our favourite blue erinaceinae fight the dastardly Doctor Eggman after accidentally teleporting to Earth.

Each episode featured a recognisable logo showing Sonic himself in profile. But it turns out that people interpreted the design in different ways thanks to an optical illusion that gives Sonic an unintended amusing expression (see our pick of the best optical illusions for more mind benders).

The logo design shows an outline of Sonic in profile. The outline should be enough to make out Sonic's features as he grits his teeth to prepare for action. But one person writes on Twitter that he grew up seeing it differently. He thought one of Sonic's ears was the hedgehog's nose, and that the nose was his bottom lip. The optical illusion gives our spiky friend look downcast and a little like he's turning up his nose at something. Some people are struggling to see it the way the user saw it, but now I've seen it, I can't unsee it.

For more logo inspiration, see our pick of the best video game logos and the animated Sonic logo.