According to interviews with Ken Sugimori in Nintendo Dream, during development, Sawk and Throh both had horns making them look more like Oni. However, they were replaced with eyebrows so as not to clash with Tornadus and Thundurus, who both were originally designed to be red and blue, like Throh and Sawk.
It's interesting to think about them as Oni rather than just generic tall/skinny and short/fat martial artists.
What do you all think?
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