You got that right, Ash: a giant!

This image is what I'd imagine what it'll be like if Ash and Pikachu were to actually encounter AZ in the X/Y anime (which the latter, sadly, didn't appear in):

After fixing the power plant in the Lumiose Badlands, our heroes proceed to Lumiose City, with Ash very eager to challenge Clemont for a Gym Leader battle. And then he ran right into someone's leg that neither he nor Pikachu saw. And that someone is an unbelievably tall man, which both surprised and spooked Ash and Pikachu as the stranger looked down at them (and Ash thought that Lt. Surge is the tallest person he ever met!). Serena, Clemont, and Bonnie arrived and were also intimidated by this man's stature. His only response, in a fatherly tone of his voice, is this: "Be careful with where you go from now on." And then he walks off, but not without mentioning about a flower Pokemon (aka Floette).

Little did Ash and co. know that the giant is actually a ruler of Kalos from long ago.

Characters (Pokemon) belong to Nintendo/Game Freak