This has been dubbed the 'hardest word search ever'. Can you find the word dog?

Crashing onto a seat on the train or bus can only be topped by having a nice, juicy word search to keep you busy as you travel home after work. But sometimes, word searches don’t exist to entertain or relax, but to keep you awake at night.

A particularly cruel word search posted to Reddit has gone viral, but it isn’t like other word searchers: there’s only one word to find.

The idea is to find the hidden “dog” before paper becomes obsolete and all your friends and family have moved to Mars alongside the rest of humankind.

Good luck.

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