India, Oct. 19 -- An optical illusion puzzle has become a big challenge for people of all ages. The picture shared by Ok_Recipe2769 on the subreddit r/mildlyinfuriating shows two cartoon cats underwater with some orange fish and plants around them. When you first look at it, it seems like a sweet underwater scene. The two cartoon cats are surrounded by bright orange fish, green plants, shiny bubbles, and little treasures. But look again. Hidden inside this colorful image are eight secret objects, and they are very well camouflaged.

This puzzle quickly became a viral optical illusion challenge. Many parents said they even struggled to find all the objects. The image is captioned as, "My 5-year-old gave up on this!" Others admitted it took...