Pokemon League Champion of the Kalos region - Diantha and her Mega Gardevoir. It's nice to see yet another female champion but it's a shame that she plays very little role in the main story as compared to all the other champions from other generations. I like how Diantha looks, her hair is neatly tied into a bun (?) and her majority of white really contrasts with champion of the Hoenn regoin - Cynthia. (Maybe I'll draw them together some time..)
Mega Gardevoir is a great add on to Gardevoir and makes her look even more graceful and pretty ;) (Wink)

I am not really a fan of mega evolution, but Mega Gardevoir is definitely one of the few that I welcome and like.