A bit of a brainteaser: What goes into the empty square?

Riddles often seem like child’s play, but can actually end up being deceivingly difficult. Some turn out to be real conundrums, which drive you crazy and even make you lose sleep! Let’s see if you are up to this particular riddle:

 

Looked much easier than it was, right? If you did manage to crack this one, you should be feeling pretty proud of yourself right now! Share with your friends, and see how it works out for them.

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Comments

Also hefty