BW/BW2 Why Black and White?

[Majora_787]

What would you have called them?
Onyx and Quartz?
With the whole Yin/Yang thing it makes sense that they're Black and White.

I honestly, if I had been told it was gonna be a yin-yang theme, would have said black and white. It really fits.

I repeat, I think they base the COLORS off the legendaries, not the other way around.