Zekrom has one of the most stand-out designs of any Legendary Dragon-type. Apart from its red eyes and the blue electricity it generates with its bulbous tail, Zekrom is entirely black.

Still, the two are pretty evenly matched, so don't count either out. Behind Blue-Eyes and Charizard, Red-Eyes Black Dragon and Dragonite are sort of like the B-Team of dragon mascots. So ...