Cats & Dog Chess Set?

Did you ever wonder where all those weird phrases came from? Like raining cats and dogs, or fighting like cats and dogs.... why are all the cats and dogs at such odds? You can even get a cat & dog chess set...queen takes bishop, felines against the canines, the winner gets the pet toy. It could be a worse I guess like raining hippos and elephants, thud, ouch that is going to leave a mark, is there insurance for this sort of thing? I don't know let me Check mate, oh that was bad!
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