New Delhi, Aug. 26 -- A new optical illusion is doing the rounds on Reddit, and it is tougher than it looks. Posted on the Reddit forum r/FindTheSniper, the photo shows what seems like a messy patch of dried and green leaves scattered across the ground. A couple of logs sit on the left, while a sheet of black plastic lies crumpled on the right. Somewhere in this busy frame, a frog is perfectly hidden - and most users could not see it right away.

The thread quickly drew hundreds of guesses. Some were confident they had spotted it, others gave up in frustration. The original poster, who goes by wildflowernatalie, gave a small hint: "he is next to the wood on the left hand side." That clue set off another round of searching.

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