Back in March 2017, a video from Santa Fe, Argentina, went viral for showing what looked like a bizarre, snake-like creature with “two heads, three eyes, and strange skin.” Over 19 million people watched the clip, trying to guess what it was.

The video was posted by Lujan Eroles, who found the creature in her yard. As it got shared over 180,000 times, people’s imaginations ran wild—some joked it looked like a Pokémon, others guessed it was some rare worm.

But the mystery was finally solved when experts identified it: a hawk moth caterpillar.

These caterpillars have an incredible defense trick. When threatened, they puff up their tails to mimic a snake’s head—complete with fake “eyes” that can even appear to blink. It’s all part of their natural mimicry to scare off predators like birds.

Though its appearance may seem creepy, the caterpillar is totally harmless to humans. This strange but fascinating creature is just one of nature’s many clever survival designs, reminding us how adaptation and illusion help even the tiniest animals survive.