New Delhi, Sept. 14 -- A brand new optical illusion is making waves online, challenging viewers to spot a cleverly hidden number in a sea of lookalikes. Solving the challenge is easier said than done. Only the most focused will find it in seconds. Are you up for the challenge? Look closely at the grid below and see how fast you can find the odd one out.

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This viral optical illusion is simple. You have to find the hidden number 10 in a grid filled with repeating 18s. The pale yellow background grid has dozens of numbers organized in rows and columns, making your eyes instantly search for anything that breaks the pattern. The challenge is simple - ...