Who is the person Steven is Mentioning in the Delta Episode?

Question

In the Delta Episode Steven tells you to meet Wallace to undo Sky Pillar's Seal, I didn't pay much attention except for when he said something about meeting Rayquaza and battling it with a guy with a black Charizard, so here I am thinking of a guy with a black Charizard

Who is the guy with the Black Charizard?

Answer 1

Steven makes a reference to the small Anime series, The Strongest Mega Evolution: Act 2. He met the protagonist of the mini series, Alain, with a Mega Charizard X, which is black. They did meet Rayquaza when Lysandre and his team were studying a mysterious giant rock that seemed to be linked to mega evolution.