A viral number illusion challenges viewers to spot the odd cell in a grid of 349s - only one shows 379, and it is harder to find than you think.

It started with a review of Piczle Cross Rune Factory, and before I knew it, I was deep down the rabbit hole, downloading all the indie nonogram games on Steam and buying every Picross title I could ...

ERR (24A: Dip your paintbrush in your coffee, say) AD SLOGAN (42D: "Red Bull Gives You Wiiings," e.g.) INSPO (54D: Creative fuel, for short) CLOSING NUMBER: The word at the end (i.e. CLOSING) of each ...

The trick here is that your eyes get used to the pattern right away. Once the brain sees row after row of the same figure, it stops searching for anything unusual. That is why the odd number blends in ...

A viral optical illusion shows a grid of 23s with one odd number hidden inside. Can you find it before we reveal the answer?